HP 6101A Service and user manual

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HEWLETT

PACKARD

HARRISON
DIVISION

MODEL 6101A

DC POWER SUPPLY

HP Part Number 06101-90001

Series Prefixed 6L, 1A, 1E, 1137A and Above

(Including Optional Modifications Listed Below)

011, 028

Microfiche No. 06101-90002

OPERATING AND SERVICE MANUAL

DC POWER SUPPLY

STB SERIES, MODEL 6101A

SERIAL NUMBER PREFIX 6L

Printed: December 2012

Stock Number: 06101-90001

TABLE OF CONTENTS

Section Page No.
I GENERAL INFORMATION 1-1
1-1. Description 1-1
1-6. Specifications 1-1
1-8. Options 1-1
1-10. Accessories 1-2
1-12. Instrument Identification 1-2
1-15. Ordering Additional Manuals 1-2

II INSTALLATION 2-1
2-1. Initial Inspection 2-1
2-3. Mechanical Check 2-1
2-5. Electrical Check 2-1
2-7. Installation Data 2-1
2-9. Location 2-1
2-11. Power Requirements 2-1
2-14. 230 Volt Operation 2-1
2-16. Power Cable 2-1
2-19. Rack Mounting 2-2
2-23. Repackaging for Shipment 2-3

III OPERATING INSTRUCTIONS 3-1
3-1. Operating Controls and
Indicators 3-1
3-3. Operating Modes 3-1
3-5. Normal Operating Mode 3-1
3-7. Constant Voltage 3-1
3-9. Current Limit 3-1
3-11. Connecting Load 3-2
3-14. Operation of Supply Beyond
Rated Output 3-2
3-16. Optional Operating Modes 3-2
3-17. Remote Programming, Constant
Voltage 3-2
3-24. Remote Resistance Programming,
Current Limit 3-3
3-27. Remote Sensing 3-3
3-32. Series Operation 3-4
3-36. Parallel Operation 3-5
3-38. Auto-Tracking Operation 3-5
3-42. Special Operating Considerations 3-5
3-43. Pulse Loading 3-5
3-45. Output Capacitance 3-6
3-48. Reverse Voltage Loading 3-6
3-50. Reverse Current Loading 3-6
3-52. Multiple Loads 3-6

Section Page No.
IV PRINCIPLES OF OPERATION 4-1
4-1. Overall Block Diagram
Discussion 4-1
4-6. Simplified Schematic 4-2
4-9. Detailed Circuit Analysis 4-3
4-10. Series Regulator 4-3
4-12. Constant Voltage Input Circuit 4-3
4-18. Driver and Error Amplifier 4-3
4-20. Current Limit Circuit 4-3
4-22. Oven Control Circuit 4-3
4-24. Reference Circuit 4-4
4-28. Meter Circuit 4-4

V MAINTENANCE 5-1
5-1. Introduction 5-1
5-3. General Measurement
Techniques 5-1
5-8. Test Equipment Required 5-1
5-10. Performance Test 5-3
5-12. Rated Output and Meter
Accuracy 5-3
5-15. Load Regulation (Front
Terminals) 5-4
5-17. Line Regulation (Front
Terminals) 5-4
5-19. Ripple and Noise 5-4
5-21. Transient Recovery Time 5-5
5-23. Output Impedance 5-5
5-25. Current Limit 5-6
5-27. Troubleshooting 5-6
5-29. Trouble Analysis 5-6
5-37. Repair and Replacement 5-8
5-39. Adjustment and Calibration 5-11
5-41. Meter Zero 5-11
5-43. Voltmeter Tracking 5-11
5-45. Ammeter Tracking 5-12
5-47. Constant Voltage Programming 5-12
Current 5-12

VI REPLACEABLE PARTS 6-1
6-1. Introduction 6-1
5-4. Ordering information 6-1
Reference Designators
Abbreviations
Manufacturers
6-8. Code List of Manufacturers 6-2
Parts List Table 6-5

i

TABLE OF CONTENTS (CONTINUED)

LIST OF TABLES

Table Page No.
1-1 Specifications 1-3
5-1 Test Equipment Required 5-2
5-2 Reference Circuit Troubleshooting 5-6
5-3 High Output Voltage Troubleshooting
5-7
5-4 Low Output Voltage Troubleshooting 5-7

LIST OF ILLUSTRATIONS

Figure Page No.
1-1 DC Power Supply iv
2-1 Input Transformer Primary
Connections 2-1
2-2 Rack Mounting, Two Units 2-2
2-3 Rack Mounting, One Unit 2-2
3-1 Front Panel Controls and Indicators 3-1
3-2 Normal Strapping Pattern 3-1
3-3 Remote Resistance Programming
(Constant Voltage) 3-2
3-4 Remote .Voltage Programming
(Constant Voltage) 3-2
3-5 Remote Resistance Programming
(Current Limit) 3-3
3-6 Remote Sensing 3-3
3-7 Normal Series Connections 3-4
3-8 Auto-Series, Two and Three Units 3-4
3-9 Normal Parallel 3-5

Table Page No.
5-5 Common Troubles 5-8
5-6 Selected Semiconductor Characteristics
5-10
5-7 Checks and Adjustments After Replace­ ment of Semiconductor Devices 5-10
5-8 Calibration Adjustment Summary 5-11

Figure Page No.
3-10 Auto-Tracking, Two and Three Units 3-5
4-1 Overall Block Diagram 4-1
4-2 Simplified Schematic 4-2
4-3 Meter Circuit, Simplified Schematic 4-4
5-1 Front Panel Terminal Connections 5-1
5-2 Output Current Measurement
Technique 5-1
5-3 Differential Voltmeter Substitute,
Test Setup 5-3
5-4 Output Current, Test Setup 5-3
5-5 Load Regulation, Test Setup 5-4
5-6 Ripple and Noise, Test Setup 5-4
5-7 Transient Recovery Time Test Setup 5-5
5-8 Transient Recovery Time, Waveforms 5-5
5-9 Output Impedance, Test Setup 5-5
5-10 Servicing Printed Wiring Boards 5-9

ii

Figure 1-1. Typical STB Power Supply

iii

SECTION 1

GENERAL INFORMATION

1-1 DESCRIPTION
1-2 The STB Series of power supplies is designed for

applications requiring extreme stability, regulation, and
insensitivity to ambient temperature variations. The
supply is completely transistorized (all-silicon) and is
suitable for either bench or relay rack operation. The
accurate programming coefficient allows the supply to
be used as a 0.1% calibrator, or as a voltage reference
source. It is a Constant Voltage / Current Limiting
supply that will furnish full rated output voltage at the
maximum rated output current or can be continuously
adjusted throughout the output range. The front panel
CURRENT controls can be used to establish the output
current limit (overload or short circuit) when the
supply is used as a constant voltage source and the
VOLTAGE controls can be used to establish the volt­age limit (ceiling) when the supply is used as a
constant current source.

1-3 The power supply has both front and rear
terminals. Either the positive or negative output
terminal may be grounded or the power supply can be
operated floating at up to a maximum of 300 volts off
ground.

1-4 A single meter is used to measure either output
voltage or output current in one of two ranges. The
voltage or current ranges are selected by a METER
switch on the front panel.

1-5 The programming terminals located at the rear of
the unit allow ease in adapting to the many operational
capabilities of the power supply. A brief description of
these capabilities is given below:

a. Remote Programming

The power supply may be programmed
from a remote Location by means of an external
voltage source or resistance.

b. Remote Sensing

The degradation in regulation which would
occur at the load because of the voltage drop in the
load leads can be reduced by using the power supply in
the remote sensing mode of operation.

c. Series and Auto Series Operation

Power Supplies may be used in series when
a higher output voltage is required in the voltage mode

of operation or when greater voltage compliance is
required in the constant current mode of operation.
Auto-Series operation permits one knob control of the
total output voltage from a "master" supply.

d. Parallel Operation

The power supply may be operated in
parallel with a similar unit when greater output current
capability is required.

e. Auto-Tracking

The power supply may be used as a
"master" supply, having control over one (or more)
"slave" supplies that furnish various voltages for a
system.

1-6 SPECIFICATIONS
1-7 Detailed Specifications for the power supply are

given in Table 1-1.
1-8 OPTIONS
1-9 Options are factory modifications of a standard

instrument that are requested by the customer. A
typical option is replacing the front panel voltage and
current controls with ten-turn voltage and current
decadial controls. The following options are available
on the instrument covered by this manual. Where
applicable, detailed coverage of options is included
throughout the manual.

Option No. Description

06 Overvoltage Protection "Crowbar": A

completely separate circuit for protecting
delicate loads against power supply
failure or operator error. This independent
device monitors the output voltage and
within 10µsec impose a virtual short­circuit (crowbar) across the power supply
output if the preset overvoltage margin is
exceeded. When Option 06 is requested
by the customer, Model 6916A is
attached to the rear of the power supply at
the factory.

Overvoltage Margin: 1 to 4 volts,

screwdriver adjustable.

Power Requirement: 15mA continuous

drain from power supply being protected.

1-1

Size: Add 5 inches to power supply

depth dimension.

Weight: Add 2 lbs. net.

NOTE

Detailed coverage of Option 06 is included in an
addendum entitled, Model 6916A Overvoltage
Protector. The addendum is included at the rear of
manuals that support power supplies that have been
modified for Option 06.

28 Rewire for 230V Input: Supply as

normally shipped is wired for 115VAC
input. Option 28 consists of reconnecting
the input transformer for 230VAC
operation.

1-10 ACCESSORIES

Part No. Description

14523A Rack Kit for mounting two 3½”-high

supplies (Refer to Section II for
details).

14525A Rack Kit for mounting two 5¼”-high

supplies (Refer to Section II for
details).

1-12 INSTRUMENT IDENTIFICATION
1-13 Hewlett-Packard power supplies are identified by

a three-part serial number tag. The first part is the
power supply model number. The second part is the
serial number prefix, which consists of a number-letter
combination that denotes the date of a significant
design change. The number designates the year, and
the letter A through L designates the month, January
through December respectively. The third part is the
power supply serial number.

1-11 The accessories listed in the following may be
ordered with the power supply or separately from the
local Hewlett-Packard field sales office (refer to list at
rear of manual for addresses).

Part No. Description

C05 8” Black Handle that can be attached

to side of supply.

14513A Rack Kit for mounting one 3½”-high

supply (Refer to Section II for details).

14515A Rack Kit for mounting one 5¼”-high

supply (Refer to Section II for details).

1-14 If the serial number prefix on your power supply
does not agree with the prefix on the title page of this
manual, change sheets are included to update the
manual. Where applicable, backdating information is
given in an appendix at the rear of the manual.

1-15 ORDERING ADDITIONAL MANUALS
1-16 One manual is shipped with each power supply.

Additional manuals may be purchased from your local
Hewlett-Packard field office (see list at rear of this
manual for addresses). Specify the model number,
serial number prefix, and Stock Number provided
on the title page.

1-2

INPUT:

105-125/210-250VAC, single phase, 48-63Hz

(cps), 0.5A, 52W.

OUTPUT:

0-20 volts at 0-1 ampere.

Table 1-1. Specifications

tects the power supply for all overloads including a
direct short placed across the output terminals.

METER:

Front panel meter and switch select 0-2.5V/

0-25V and 0-120mA/0-1.2A scales.

LOAD REGULATION:

Front terminals: Less than 0.001% plus 600µV.
Rear terminals: Less than 0.001% plus 100µV.
For an output current change from no load to

full load.
LINE REGULATION:

Less than 0.001% output change for any line

voltage change within the input rating.

RIPPLE AND NOISE:

At any line voltage and under any load condition

within rating.

Less than 100µV peak-to-peak.
Less than 40µV rms.

TEMPERATURE COEFFICIENT:

After 30 minutes warm-up
Front panel control: Less than 0.005% plus

30µV per degree Centigrade.

Remote programming: Less than 0.001% plus

10µV per degree Centigrade.

STABILITY:

Total drift after 30 minutes warm-up and with less

than ±3°C ambient temperature variation.

Front panel control: Less than 0.01% plus

300µV for 8 hours.

Remote programming: Less than 0.01% plus

100µV for 8 hours.

Less than 0.012% + 120µV for one month.

TEMPERATURE RANGES:

Operating: 0 to 50°C. Storage: -20 to +85°C.

OUTPUT IMPEDANCE:

Less than 0.002 ohms from DC to 100 Hz.
Less than 0.02 ohms from 100 Hz to 1 kHz.
Less than 0.5 ohms from 1 kHz to 100 kHz.
Less than 3 ohms from 100 kHz to 1 MHz.

TRANSIENT RECOVERY TIME:

Less than 50 microseconds for output recovery to
within 10 millivolts of the nominal output voltage
following a full load current change. Less than 100
microseconds for output recovery to within load
regulation specification.

OVERLOAD PROTECTION:

A continuously variable current limit circuit pro-

OUTPUT CONTROLS:

A ten-turn coarse and one-turn fine voltage
control enable high resolution voltage adjustment.
A single turn front panel pot permits the current
limit setting to be varied continuously from zero to
a value slightly in excess of the full current rating.

OUTPUT TERMINALS:

Three "five-way" output posts are provided on
the front panel and an output barrier strip is located
on the rear of the chassis. All power supply output
terminals are isolated from the chassis and either
the positive or negative terminal may be connected
to the chassis through a separate ground terminal
located on the output terminal strip.

ERROR SENSING:

Error sensing is automatically accomplished at
the front terminals if the load is attached to the
front terminals or at the rear terminals if the load is
attached to the rear terminals. Provision is also
included on the rear terminal strip for remote error
sensing.

REMOTE PROGRAMMING:

Remote programming of the output voltage is
made available at the rear terminals. The
programming coefficient is 1000 ohms per volt
with an accuracy of 0.1% plus 1 millivolt. The
current limit may also be set remotely by means of
a resistance, 1000 ohms corresponding
approximately to full output current.

COOLING:

Convection cooling is employed. The supply
has no moving parts.

SIZE:

3-½" H x 8-½" W x 12-⅝" D. Two units can
be mounted side by side to take up the same space
as a standard 3-½" x 19" relay rack mounting.

WEIGHT: 10 lbs. net, 13 lbs. shipping.
FINISH: Light gray front panel with dark gray case.
POWER CORD:

A 3-wire, 5-foot power cord is provided with
each unit.

1-3

SECTION II

45

46

47

48

S1

FUSE
/115V

45

46

47

48

S1

FUSE
/230V

INSTALLATION

2-1 INITIAL INSPECTION
2-2 Before shipment, this instrument was inspected

and found to be free of mechanical and electrical
defects. As soon as the instrument is unpacked,
inspect for any damage that may have occurred in
transit. Save all packing materials until the inspection
is completed. If damage is found, proceed as described
in the Claim for Damage in Shipment section of the
Warranty at the rear of this manual.

2-3 MECHANICAL CHECK
2-4 This check confirms that there are no broken

knobs or connectors, that the cabinet and panel
surfaces are free of dents and scratches, and that the
meters are not scratched or cracked.

2-5 ELECTRICAL CHECK
2-6 The instrument should be checked against its

electrical specifications. Section V includes an "in­cabinet" performance check to verify proper
instrument operation.

2-7 INSTALLATION DATE
2-8 The instrument is shipped ready for bench

operation. It is only necessary to connect the in­strument to a source of power and it is ready for
operation.

2-9 LOCATION
2-10 This instrument is air cooled. Sufficient space

should be provided around the instrument to permit
free flow of cooling air along the sides and to the rear.
It should be used in an area where the ambient
temperature does not exceed 50°C (122°F).

a 115 volt source. To convert the power supply for
operation from a 230 volt source, the power
transformer windings must be connected in series. The
windings are connected in series as follows: (Refer to
Figure 2-1).

TRANSFORMER PRIMARY TRANSFORMER PRIMARY
CONNECTED FOR CONNECTED FOR
115 VOLT OPERATION 230 VOLT OPERATION

Figure 2-1. Input Transformer Primary Connections

a. Unplug the line cord and remove the top and

bottom covers from the case. (This is done by
removing the four screws which hold each cover to the
side frames.)

b. With a sharp knife or razor blade, cut the

printed wiring between test points 45 and 46 and also
between 47 and 48 on the printed circuit board. These
are shown on the overall schematic and are labeled on
the printed circuit board.

c. Connect a jumper wire between 46 and 47.
d. Replace the fuse with a 1 ampere 230 volt

fuse. Replace covers and operate unit normally.
2-16 POWER CABLE

2-11 POWER REQUIREMENTS
2-12 This power supply may be operated from either a

115 or 230 volt. 48-63 cps power source. The unit, as
shipped from the factory, is wired for 115V operation.

2-13 The input power required when operating at full
load from a 115 volt, 60 cycle power source is 45
watts and 0.5 amperes.

2-14 230 VOLT OPERATION
2-15 Normally, the windings of the input trans-

former are connected in parallel for operation from

2-17 To protect operating personnel, the National
Electrical Manufacturers Association (NEMA)
recommends that the instrument panel and cabinet be
grounded. This instrument is equipped with a three
conductor power cable. The third conductor is the
ground conductor and when the cable is plugged into
an appropriate receptacle, the instrument is grounded.
The offset pin on the power cable three prong
connector is the ground connection.

2-18 To preserve the protection feature when operating
the instrument from a two-contact outlet, use a three­prong to two-prong adaptor and connect the green lead
on the adaptor to ground.

2-1

5V

50V 0.6A

0.06A

METER

CURRENT

VOLTAGE

COARSE FINE

DC POWER SUPPLY

HARRISON
HEWLETT-PACKARD

5V

50V 0.6A

0.06A

METER

CURRENT

VOLTAGE

COARSE FINE

DC POWER SUPPLY

HARRISON
HEWLETT-PACKARD

Figure 2-2. Rack Mounting, Two Units

5V

50V

0.6
A

0.06
A

METE

R

CURRENT

VOLTAGE

COARSE FINE

DC POWER SUPPLY

HARRISON
HEWLETT-PACKARD

2-19 RACK MOUNTING
2-2 This instrument may be rack mounted in a standard

19 inch rack panel either alongside a similar unit or by
itself. Figures 2-2 and 2-3 show how both types of
installations are accomplished.

2-21 To mount two units side-by-side, proceed as
follows:

a. Remove the four screws from the front

panels of both units.

b. Slide rack mounting ears between the

front panel and case of each unit.

c. Slide combining strip between the front

panels and cases of the two units.

d. After fastening rear portions of units together

using the bolt, nut, and spacer, replace panel screws.
2-22 To mount a single unit in the rack panel, proceed as

follows:

a. Bolt rack mounting ears, combining straps,

and angle brackets to each side of center spacing panels.
Angle brackets are placed behind combining straps as
shown in Figure 2-3.

b. Remove four screws from front panel of unit.
c. Slide combining strips between front

panel and case of unit.

d. Bolt angle brackets to front sides of case and

replace front panel screws.

Figure 2-3. Rack Mounting, One Unit

2-2

2-23 REPACKAGING FOR SHIPMENT
2-24 To insure safe shipment of the instrument, it is

recommended that the package designed for the
instrument be used. The original packaging material is
reusable. If it is not available, contact your local
Hewlett-Packard field office to

obtain the materials. This office will also furnish the
address of the nearest service office to which the
instrument can be shipped. Be sure to attach a tag to
the instrument which specifies the owner, model
number, full serial number, and service required, or a
brief description of the trouble.

2-3

SECTION III

0

10

20 30

40

50

5V

50V 0.6A

0.06A

METER

CURRENT

VOLTAGE

COARSE FINE

.1

.2.3.4

.5

0

AMPERES

VOLTS

DC POWER SUPPLY

HARRISON
HEWLETT-PACKARD

METER SWITCH

CURRENT LIMIT

CONTROL

OUTPUT TERMINALS

COARSE OUTPUT

VOLTAGE CONTROL

FINE OUTPUT

VOLTAGE CONTROL

PILOT LIGHT

1

2

3

4

5

.6

A1 A2 A3 A4 A5 A6 A7 +S + G – –S A8 A9 A10

LOAD

MONITORING

POINT

OPERATING INSTRUCTIONS

3-1 OPERATING, CONTROLS AND INDICATORS
3-2 The front panel controls and indicators, to-

gether with the normal turn-on sequence, are shown in
Figure 3.1.

1. PUSH LINE SWITCH TO TURN ON SUPPLY AND

OBSERVE THAT LIGHT GOES ON.

2. SET METER SWITCH TO DESIRED VOLTAGE RANGE.

3. ADJUST COARSE AND FINE VOLTAGE CONTROLS UNTIL

DESIRED OUTPUT VOLTAGE IS INDICATED ON METER.

4. SHORT CIRCUIT OUTPUT TERMINALS AND SET METER

SWITCH TO DESIRED CURRENT RANGE.

5. ADJUST CURRENT CONTROL FOR DESIRED OUTPUT

CURRENT.

6. REMOVE SHORT AND CONNECT LOAD TO OUTPUT

TERMINALS (FRONT OR REAR).

7. POWER IS REMOVED BY PUSHING THE LINE SWITCH.

TURN-ON SEQUENCE

Figure 3-1. Front Panel Controls and Indicators

3-3 OPERATING MODES

3-5 NORMAL OPERATING MODE
3-6 The power supply is normally shipped with its

rear terminal strapping connections arranged for
Constant Voltage / Current Limiting, local sensing,
local programming, single unit mode of operation. This
strapping pattern is illustrated in Figure 3-2. The
operator selects either a constant voltage or current
limited output using the front panel controls (local
programming, no strapping changes are necessary).

Figure 3-2. Normal Strapping Pattern

3-7 CONSTANT VOLTAGE
3-8 To select a constant voltage output, proceed as

follows:

a. Turn-on power supply and adjust

VOLTAGE controls for desired output voltage (output
terminals open).

b. Short output terminals and adjust CUR-

RENT controls for maximum output current allowable
(current limit), as determined by load conditions. If a
load change causes the current limit to be exceeded, the
power supply will automatically crossover to constant
current output at the preset current limit and the output
voltage will drop proportionately. In setting the current
limit, allowance must be made for high peak current
which can cause unwanted crossover. (Refer to
Paragraph 3-43.)

3-4 The power supply is designed so that its mode of
operation can be selected by making strapping
connections between particular terminals on the
terminal strip at the rear of the power supply. The
terminal designations are stenciled in white on the
power supply above their respective terminals. Al­through the strapping patterns illustrated in this section
show the negative terminal grounded, the operator can
ground either terminal or operate the power supply up
to 300 vdc off ground (floating). The following
paragraphs describe the procedures for utilizing the
various operational capabilities of the power supply. A
more theoretical description is contained in a power
supply Application Manual and in various Tech.
Letters published by the Harrison Division. Copies of
these can be obtained from your local Hewlett-Packard
field office.

3-9 CURRENT LIMIT
3-10 To select a current limit output, proceed as

follows:

a. Short output terminals and adjust CUR-

RENT controls for desired output current.

b. Open output terminals and adjust VOLT-

AGE controls for maximum output voltage allowable
(voltage limit), as determined by load conditions. If a
load change causes the voltage limit to be exceeded,
the power supply will automatically crossover to
constant voltage output at the preset voltage limit and
the output current will drop proportionately. In setting
the voltage limit, allowance must be made for high
peak voltages which can cause unwanted crossover.
(Refer to Paragraph 3-43.)

3-1

3-11 CONNECTING LOAD

A1 A2 A3 A4 A5 A6 A7 +S + G – –S A8 A9 A10

LOAD

PROGRAMMING

RESISTOR

(1000 OHMS PER VOLT)

LOAD MAY BE TAKEN
FROM FRONT OR REAR
TERMINALS AS DESIRED

A1 A2 A3 A4 A5 A6 A7 +S + G – –S A8 A9 A10

LOAD

REFERENCE

VOLTAGE

+

R

X

(<6K)

3-12 Each load should be connected to the power
supply output terminals using separate pairs of
connecting wires. This will minimize mutual coupling
effects between loads and will retain full advantage of
the low output impedance of the power supply. Each
pair of connecting wires should be as short as possible
and twisted or shielded to reduce noise pickup. (If
shield is used, connect one end to power supply ground
terminal and leave the other end unconnected.)

3-13 If load considerations require that the output
power distribution terminals be remotely located from
the power supply, then the power supply output
terminals should be connected to the remote
distribution terminals via a pair of twisted or shielded
wires and each load separately connected to the remote
distribution terminals. For this case, remote sensing
should be used (Paragraph 3-27).

3-14 OPERATION OF SUPPLY BEYOND RATED OUTPUT
3-15 The shaded area on the front panel meter face

indicates the amount of output voltage or current that is
available in excess of the normal rated output.
Although the supply can be operated in this shaded
region without being damaged, it cannot be guaranteed
to meet all of its performance specifications. However,
if the line voltage is maintained above 115 Vac, the
supply will probably operate within its specifications.

3-16 OPTIONAL OPERATING MODES
3-17 REMOTE PROGRAMMING, CONSTANT VOLTAGE
3-18 The constant voltage output of the power supply

can be programmed (controlled) from a remote location
if required. Either a resistance or voltage source can be
used for the programming device. The wires
connecting the programming terminals of the supply to
the remote programming device should be twisted or
shielded to reduce noise pick-up. The VOLTAGE
controls on the front panel are disabled according to the
following procedures.

Figure 3-3. Remote Resistance Programming

(Constant Voltage)

3-20 The output voltage of the power supply should be
zero volts ±1 millivolt when zero ohms is connected
across the programming terminals. If a zero ohm
voltage closer than this is required, it may be achieved
by changing resistor R14 as described in Paragraph 5-

48.
3-21 To maintain the stability and temperature co-

efficient of the power supply, use programming
resistors that have stable, low noise, and low
temperature characteristics (less than 5 ppm per degree
Centigrade). A switch can be used in conjunction with
various resistance values in order to obtain discrete
output voltages. The switch should have make-before­break contacts to avoid momentarily opening the
programming terminals during the switching interval.

3-22 Voltage Programming (Figure 3-4). Employ the
strapping pattern shown on Figure 3-4 for voltage
programming. In this mode, the output voltage will
vary in a 1 to 1 ratio with the programming voltage
(reference voltage) and the load on the programming
voltage source will not exceed 0.5 microampere.

3-19 Resistance Programming (Figure 3-3). In this
mode, the output voltage will vary at a rate determined
by the programming coefficient--1000 ohms per volt
(i.e. the output voltage will increase 1 volt for each
1000 ohms added in series with programming
terminals). The programming coefficient is determined
by the programming current. This current is adjusted to
within 0.1% of l mA at the factory. If greater
programming accuracy is required, it may be achieved
by changing resistor R16.

Figure 3-4. Remote Voltage Programming

(Constant Voltage)

3-2

3-23 The impedance (RX) looking into the external

A1 A2 A3 A4 A5 A6 A7 +S + G – –S A8 A9 A10

LOAD

PROGRAMMING

RESISTOR

(≈1K FOR FULL LOAD)

A1 A2 A3 A4 A5 A6 A7 +S + G – –S A8 A9 A10

LOAD

NOTE:

IF TRANSIENT RESPONSE IS POOR
OR POWER SUPPLY OSCILLATES
REMOVE JUMPER FROM A7 TO (+)
AND ADD CAPACITOR C

X

AT LOAD

CX (200µF 150V)

programming voltage source should be approximately
6000 ohms if the temperature and stability specifi­cations of the power supply are to be maintained.

3-24 REMOTE RESISTANCE PROGRAMMING,

CURRENT LIMIT (See Figure 3-5)

3-25 The output current will vary roughly in propor­tion to the programming resistor. Full current output is
obtained with approximately 1000 ohms; however, the
exact current setting should be checked by shorting the
output terminals and reading the current with the
programming resistor in place.

3-27 REMOTE SENSING (See Figure 3-6)
3-26 Remote sensing is used to maintain good

regulation at the load and reduce the degradation of
regulation which would occur due to the voltage drop
in the leads between the power supply and the load.
Remote sensing is accomplished by utilizing the
strapping pattern shown in Figure 3-6. The power
supply should be turned off before changing strapping
patterns. The leads from the +S terminals to the load
will carry approximately 1 milliampere of current, and
it is not required that these leads be as heavy as the
load leads. However, they must be twisted or shielded
to minimize noise pick-up.

Figure 3-5. Remote Resistance Programming

(Current Limit)

3-26 Use stable, low noise, low temperature coefficient
(less than 5 ppm/°C) programming resistors to maintain
the power supply temperature coefficient and stability
specifications. A switch may be used to set discrete
values of output current. A make-before-break type of
switch should be used since the output current will
exceed the maximum rating of the power supply if the
switch contacts open during the switching interval.

CAUTION

If the programming terminals (Al and A9)
should open at any time during this mode, the
output current will rise to a value that may
damage the power supply and/or the load. To
avoid this possibility, connect a 1KΩ resistor
across the programming terminals and in
parallel with a remote programming resistor.
Like the programming resistor, the 1KΩ
resistor should be of the low noise, low
temperature coefficient type.

Figure 3-6. Remote Sensing

CAUTION

Observe polarity when connecting the
sensing leads to the load.

3-29 Note that it is desirable to minimize the drop in
the load leads and it is recommended that the drop not
exceed 1 volt per lead if the power supply is to meet its
DC specifications. If a larger drop must be tolerated,
please consult a Hewlett-Packard field representative.

3-30 The procedure just described will result in a low
DC output impedance at the load. If a low AC
impedance is required, it is recommended that the
following precautions be taken:

a. Disconnect output capacitor C3, by

disconnecting the strap between A7 and (+).

3-3

b. Connect a capacitor having similar char-

A1 A2 A3 A4 A5 A6 A7 +S + G – –S A8 A9 A10

A1 A2 A3 A4 A5 A6 A7 +S + G – –S A8 A9 A10

A1 A2 A3 A4 A5 A6 A7 +S + G – –S A8 A9 A10

A1 A2 A3 A4 A5 A6 A7 +S + G – –S A8 A9 A10

LOAD

MASTER

R

X

R

X

LOAD

SLAVE

A1 A2 A3 A4 A5 A6 A7 +S + G – –S A8 A9 A10

R

X

R

X

LOAD

A1 A2 A3 A4 A5 A6 A7 +S + G – –S A8 A9 A10

R

X

R

X

acteristics (approximately same capacitance, same
voltage rating or greater, and having good high fre­quency characteristics) across the load using short
leads.

3-31 Although the strapping patterns shown in Figures
3-3 through 3-5 employ local sensing, note that it is
possible to operate a power supply simultaneously in
the remote sensing end Constant Voltage/Current Limit
remote programming modes.

NOTE

It is necessary to re-adjust the current
limit when the instrument is operated in
the remote sensing mode.

3-32 SERIES OPERATION
3-33 Normal Series Connections (Figure 3-7). Two or

more power supplies can be operated in series to obtain
a higher voltage than that available from a single
supply. When this connection is used, the output
voltage is the sum of the voltages of the individual
supplies. Each of the individual supplies must be
adjusted in order to obtain the total output voltage. The
power supply contains a protective diode connected
internally across the output which protects the supply if
one power supply is turned off while its series
partner(s) is on.

3-34 Auto-Series Connections (Figure 3-8). The Auto­Series configuration is used when it is desirable to
have the output voltage of each of the series connected
supplies vary in accordance with the setting of a
control unit. The control unit is called the master; the
controlled units are called slaves. At maximum output
voltage, the voltage of the slaves is determined by the
setting of the front panel VOLTAGE control on the
master. The master supply must be the most positive
supply of the series. The output CURRENT controls
of all series units are operative and the current limit is
equal to the lowest control setting. If any output
CURRENT controls are set too low, automatic
crossover to constant current operation will occur and
the output voltage will drop. Remote sensing and
programming can be used; however, the strapping
arrangements shown in the applicable figures show
local sensing and programming.

Figure 3-7. Normal Series

Figure 3-8. Auto-Series, Two and Three Units

3-35 In order to maintain the temperature coefficient
and stability specifications of the power supply, the
external resistors (Rx) shown in Figure 3-8 should be
stable, low noise, low temperature coefficient (less than
5 ppm per degree Centigrade) resistors. The value of
each resistor is dependant on the desired output voltage
ratings of the master and slave supplies. The value of
Rx is this voltage divided by the voltage programming
current of the supply, 1mA (1/KP where KP is the
voltage programming coefficient).

3-4

3-36 PARALLEL OPERATION (Figure 3-9).

A1 A2 A3 A4 A5 A6 A7 +S + G – –S A8 A9 A10

LOAD

A1 A2 A3 A4 A5 A6 A7 +S + G – –S A8 A9 A10

A1 A2 A3 A4 A5 A6 A7 +S + G – –S A8 A9 A10

R

A

R

B

LOAD #1

LOAD #2

* MASTER MUST BE
POSITIVE SUPPLY
SLAVE MAY BE
EITHER POLARITY

MASTER*

A1 A2 A3 A4 A5 A6 A7 +S + G – –S A8 A9 A10

R

A

R

B

A1 A2 A3 A4 A5 A6 A7 +S + G – –S A8 A9 A10

R

C

R

D

LOAD #1

LOAD #2

LOAD #3

3-37 Two or more power supplies can be connected in
parallel to obtain a total output current greater than that
available from one power supply. The total output
current is the sum of the output currents of the
individual power supplies. The output CURRENT
controls of each power supply can be separately set.
The output voltage controls of one power supply
should be set to the desired output voltage; the other
power supply should be set for a slightly larger output
voltage. The supply set to the lower output voltage will
act as a constant voltage source; the supply set to the
higher output will act as a constant current source,
dropping its output voltage until it equals that of the
other supply.

Figure 3-9. Normal Parallel

3-38 AUTO TRACKING OPERATION (See Figure 3-10.)
3-39 This connection is used when it is necessary to

provide several voltages, all referred to a common
bus, which vary in proportion to the setting of one
master instrument. The following constraints must be
observed when using this connection.

a. The master unit must be a positive voltage

source. When several positive sources are used, the
master must be the largest voltage unit.

b. The external resistors should be stable, low

noise, low temperature coefficient resistors if the
instruments are to maintain their temperature co­efficient and stability specifications.

3-40 The resistor values are determined as follows:
Referring to Figure 3-10 for two units.



   









Choosing 10 milliamperes as a reasonable maximum



current in the resistors RA= 100(V master – V slave)
and RB = 100 (V slave).

3-41. For several units connected in auto tracking
refer to Figure 3-10. RA and RB are determined as
before. RC = 100 (V master – V slave2), RD 100 (V
slave2), etc.

Figure 3-10. Auto-Tracking. Two and Three Units

3-42 SPECIAL OPERATING CONSIDERATIONS
3-43 PULSE LOADING

3-44 The power supply wilt automatically crossover
from constant voltage to constant current operation, or
the reverse, in response to an increase (over the preset
limit) in the output current or voltage, respectively.
Although the preset limit may be set higher than the
average output current or voltage, high peak currents or
voltages (as occur in pulse loading) may exceed the
preset limit and cause crossover to occur. If this
crossover limiting is not desired, set the preset limit for
the peak requirement and not the average.

3-5

3-45 OUTPUT CAPACITANCE
3-46 There is a capacitor (internal) across the output

terminals of the power supply. This capacitor helps to
supply high-current pulses of short duration during constant
voltage operation. Any capacitance added externally will
improve the pulse current capability, but will decrease the
safety provided by the constant current circuit. A high­current pulse may damage load components before the
average output current is large enough to cause the constant
current circuit to operate.

3-47 The effects of the output capacitor during constant
current operation are as follows:

a. The output impedance of the power supply

decreases with increasing frequency.

b. The recovery time of the output voltage is longer

for load resistance changes.

c. A large surge current causing a high power

dissipation in the load occurs when the load resistance is
reduced rapidly.

3-48 REVERSE VOLTAGE LOADING
3-49 A diode is connected across the output terminals.
Under normal operating conditions, the diode is reverse
biased (anode connected to negative terminal). If a reverse

voltage is applied to the output terminals (positive voltage
applied to negative terminal), the diode will conduct,
shunting current across the output terminals and limiting the
voltage to the forward voltage drop of the diode. This diode
protects the series transistors and the output electrolytic
capacitors.

3-50 REVERSE CURRENT LOADING
3-51 Active loads connected to the power supply may

actually deliver a reverse current to the power supply during
a portion of it's operating cycle. An external source cannot
be allowed to pump current into the supply without loss of
regulation and possible damage to the output capacitor. To
avoid these effects, it is necessary to preload the supply with
a dummy load resistor so that the power supply delivers
current through the entire operating cycle of the load device.

3-52 MULTIPLE LOADS
3-53 It is imperative that each load taken from the power

supply have two separate leads brought back to the power
supply output terminals if full advantage is to be taken of
the low output impedance of the power supply and if mutual
coupling effects between loads are to be avoided.

3-6

SECTION IV

POWER

TRANSFORMER

AC

INPUT

REFERENCE

BIAS

SUPPLY

RECTIFIER
AND
FILTER

SERIES
REGULATOR

BIAS
VOLTAGE

OVEN
CONTROL
CIRCUIT

BIAS
VOLTAGES

CURRENT

LIMITING

CIRCUIT

CONSTANT
VOLTAGE
INPUT
CIRCUIT

CURRENT
SAMPLING
RESISTOR

METER
CIRCUIT

M

+

-

+

-

NOTE:

DENOTES VOLTAGE
FEEDBACK PATH
DENOTES CURRENT
LIMIT PATH

PRINCIPLES OF OPERATION

Figure 4-1. Overall Block Diagram

4-1 OVERALL BLOCK DIAGRAM DISCUSSION
4-2 The power supply, Figure 4-1, consists of a power

transformer, rectifier and filter, series regulator, error
amplifier and driver, constant voltage input circuit,
current limiting circuit, reference regulator circuit, bias
supply, meter circuit, and an oven control circuit.

4-3 The ac input line voltage is reduced to the proper
level and coupled to the rectifier and filter. The rectifier­filter converts the ac input to raw dc which is fed to the
positive terminal via the regulator and current sampling
resistor network. The regulator, part of the feedback
loop, is made to alter it's conduction to maintain a
constant output voltage or limit the output current. The
voltage developed across the current sampling resistor
network is the input to the current limiting circuit. If the
output current that passes through the sampling network
exceeds a certain predetermined level, the current
limiting circuit applies a feedback signal to the series
regulator which alters the regulator's conduction so that
the output current does not exceed the predetermined
current limit.

4-4 The constant voltage input circuit obtains it's input
by sampling the output voltage of the supply. Any
changes in output voltage are detected in the constant
voltage input circuit, amplified by the error amplifier
and driver, and applied to the series regulator in the
correct phase and amplitude to counteract the change in
output voltage. The reference regulator circuit provides
stable reference voltages which are used by the constant
voltage input circuit and the current limiting circuit for
comparison purposes. The bias supply furnishes
voltages which are used throughout the instrument for
biasing purposes. The meter circuit provides indications
of output voltage or current in either operating mode.

4-5 An oven houses the temperature sensitive
components in the supply to provide a low temperature
coefficient which results in excellent stability. The
oven control circuit maintains the oven temperature at
65°C.

4-1

F1

R55

DS1

115V

S1
ON/OFF
SWITCH

CR27

CR26

C17

­+

CR29

CR30

CR24

CR25

C25

­+

REFERENCE
REGULATOR

Q12-Q15

+6.2V
+S

-9.4V
+12.4V

OVEN

CONTROL

CIRCUIT

Q16

20V

SERIES

REGULATOR

Q11

C19

R54

NOTE 1

CR13

2.5V

CURRENT
LIMITING
CIRCUIT
Q5

DRIVER
Q10

ERROR
AMPL.
Q7,Q8,Q9

VOLTAGE
INPUT
CIRCUIT
Q1,Q3

-9.4V

R23

CURRENT
SAMPLING
RESISTOR

METER
CIRCUIT
S2

M

+

-

+OUT

-OUT

CURRENT
CONTROL

R25

-9.4V

R20

+

-

C4

+

-

CONSTANT

VOLTAGE

PULLOUT

RESISTOR

+6.2V

CR32

C23

FINE
VOLTAGE
ADJ.
R11

+12.4V

30V

+O
+S
A7
A2

A3
A5
A6

A8

-S

-O

A10
A9

COARSE
VOLTAGE
ADJ.

4

3
2

1

6

8

7

11

10

9

12

13

14

NOTE 1: MAIN SUPPLY OUTPUT
VOLTAGES ARE:

4-6 SIMPLIFIED SCHEMATIC
4-7 A simplified schematic of the power supply is

shown in Figure 4-2. It illustrates the operating
controls; the ON-off switch, and the voltage
programming controls (R11 and R20). Figure 4-2 also
shows the internal sources of bias and reference
voltages and their nominal magnitudes with an
input of 115 Vac.

MODEL 6101A 6102A 6106A 6111A 6112A 6113A 6116A
VDC 25 60 132 25 60 13 132

Figure 4-2. Simplified Schematic

4-8 Diode CR32, connected across the output terminals
of the power supply, is a protective device which
prevents internal damage that might occur if a reverse
voltage were applied across the output terminals. Output
capacitor, C23, is also connected across the output
terminals when the normal strapping pattern shown on
Figure 4-2 is employed. Note that this capacitor can
be removed if an increase in the programming speed is
desired.

4-2

4-9 DETAILED CIRCUIT ANALYSIS
(Refer to Overall Schematic at Rear of Manual.)

4-10 SERIES REGULATOR
4-11 The series regulator consists of transistor stage

Q11. The regulator serves as a series control element by
altering it’s conduction so that the output voltage and
the current limit is never exceeded. The conduction of
Q11 is controlled by the feedback voltage obtained from
driver Q10.

4-12 CONSTANT VOLTAGE INPUT CIRCUIT
4-13 This circuit consists of the programming resistors,

coarse voltage adjustment R20, fine voltage adjustment
R11, and differential amplifiers Ql, Q2-Q3, and Q7-Q8.
Ql consists of two transistors having closely matched
characteristics in a single transistor package. This
package insures that both transistors will operate at
essentially the same temperature, minimizing drift due
to thermal differentials. Ql, Q2, and Q3 are enclosed in a
constant-temperature oven to further minimize the
effects of changing ambient temperature.

4-14 The constant voltage input circuit continuously
compares a fixed reference voltage with a portion of the
output voltage and, if a difference exists, produces an
error voltage whose amplitude and phase is proportional
to the difference. The error output is fed back to the
series regulator, through the error and driver amplifiers.
The error voltage changes the conduction of the series
regulator which, in turn, alters the output voltage so that
the difference between the two input voltages applied to
the differential amplifier is reduced to zero. The above
action maintains the output voltage constant.

4-15 The base of Q1A is connected to the junction of
the programming resistors and the current pullout
resistor (R18 or R19) through a current limiting
resistor, R1. Note that when internal programming is
used, R19 is the current pullout resistor, having similar
temperature characteristics as the front panel voltage
control. In remote programming, R18 is the current
pullout, having as low a temperature coefficient as
possible. Diodes CR1 and CR2 limit voltage
excursions on the base of Q1A. R1 limits the current
through the programming resistors under the condition
of rapid voltage turndown. Capacitor C4 shunts the
programming resistor to increase the high frequency
gain of the amplifier. The programming current is
determined primarily by the reference voltage and the
pullout resistor, R18 or R19. R17 in series with the
pullout resistor serves as a trimming adjustment of the
programming current.

A variable current injected at the junction of the
programming and pullout resistors through R15 allows
fine trimming of the programming current.

4-16 The base of Q1B is connected to ground through
R2. Variable currents can be injected at this point
through R13 which serves to compensate for fixed
voltage offsets in Ql, and through R11 which is the
fine voltage adjustment.

4-17 Negative feedback is coupled from the output of
differential amplifier Q7-Q8 to the input of Q1 by
network R30 and C6. This feedback provides high
frequency roll off in the loop gain to stabilize the
feedback loop.

4-18 DRIVER AND ERROR AMPLIFIER
4-19 The driver and error amplifier circuit raises the

level of the error signal from the constant voltage input
circuit to a sufficient amount to drive the series
regulator. Common emitter amplifier Q10 also receives
a current limiting input when CR8 becomes forward
biased.

4-20 CURRENT LIMIT CIRCUIT
4-21 The output current flows through R23 producing a

voltage drop of one volt for 500 mA output current.
Current limit control, R25 is attached to R23 and goes
positive as the output current increases. When this
positive voltage is great enough to overcome the
negative voltage resulting from the current limit control
setting Q5 is turned on. This action causes test point 21
to fall to about zero volts, forward biasing CR8 and
carrying the base of Q10 sufficiently negative to turn it
off, thus turning off the series regulator. R27 and CR4
provide a -0.7V bias for the emitter of Q5.

4-22 OVEN CONTROL CIRCUIT
4-23 The oven temperature is sensed by thermistor R57.

If the temperature is too low, the resistance of R57 will
be high enough to bias the emitter of unijunction
transistor Q16 sufficiently positive for it to act as a free­running pulse generator. These pulses are coupled
through C23 and R62 to the gate of the Silicon­Controlled Rectifier CR31. The first pulse in any half­cycle of line voltage will cause CR31 to conduct and
remain conducting to the end of that half-cycle. When
CR31 is conducting, current flows through the oven
heater winding raising the temperature. When the
temperature is high enough, R57 will have decreased
sufficiently to lower the emitter bias of Q16, stopping its
output pulses and leaving CR31 off.

4-3

4-24 REFERENCE CIRCUIT

MODEL

6101A

6102A

6106A

6111A

6112A

6113A

6116A 1 2.5V

5V

12V

2.5V

5V

2.5V

12V 2 25V

50V

120V

25V

50V

25V

120V 3 1.2A

.6A

.25A

1.2A

.6A

2.5A

.25A 4 .12A

.06A

.025A

.12A

.06A

.25A

.025A

CURRENT
SAMPLING

R23

R67

VOLTAGE

CAL

R69

R21

R66

SELECTED

1

2 3

4

1

2

3

4

M

THERMISTOR

R22

R42

+

-

S2C S2B

A. VOLTAGE MONITORING

-OUT

+

R23

CURRENT

SAMPLING

3

4

S2A

R42

R22

THERMISTOR

R64

R65

R50

CURRENT

CAL

2

1

M

+ -

3

4

S2B

2

1

R66

SELECTED

-OUT

B. CURRENT MONITORING

+

4-25 The reference circuit is a feedback power supply
similar to the main supply. It provides stable reference
voltages which are used throughout the unit. The
reference voltages are all derived from raw dc obtained
from the full wave rectifier (CR24 and CR25) and filter
capacitor C16. The +6.2 and –9.4 voltages, which are
used in the constant voltage input circuit for comparison
purposes, are developed across temperature com­pensated Zener diodes VR1 and VR2. Resistor R49
limits the current through the Zener diodes to establish
an optimum bias level.

4-26 The reference circuit is a closed loop feedback
regulator which acts to maintain the voltage at point 16
at 12.4 volts regardless of line voltage variation. Any
difference between the zener reference diode VR1 and
one-half of the 12.4 volt bus as sampled by R47 and
R48 is amplified by Q14 and Q15 connected as a
differential amplifier. The error is further amplified by
Q13 and is applied to the base of series regulator Q12
which controls the output voltage of the reference
circuit.

4-27 Zener diode VR2 is added in series with the
reference outputs to provide a –9.4 volt bias output. The
main reference voltage is the +6.2 volt zener VR1. The

12.4 volt output is used as a stable bias source. Diode
CR19 provides initial start-up bias for the reference
circuit when the power supply is first turned on.

S2 SWITCH POSITIONS

4-28 METER CIRCUIT
4-29 The meter circuit provides continuous indications

of output voltage or current on a single multiple range
meter. The meter can be used either as a voltmeter or an
ammeter depending upon the position of METER switch
S2 on the front panel of the supply. This switch also
selects one of two meter ranges on each scale. The meter
circuit consists of METER switch S2, various
multiplying resistors and the meter movement.

4-30 With METER switch S2 set to either voltage
position 1 or 2 (Figure 4-3A), the meter is connected in
series with R21, R69, R66, R22, and R42 across the
output of the supply. Resistor R66 calibrates the meter
for full scale deflection to compensate for slight
resistance variations inherent in different meter
movements. Thermistor R22 compensates for the
change in meter resistance as a function of temperature,
and R42 linearizes the resistance slope of R22 to match
the meter resistance slope.

4-31 Voltage Adjust potentiometer R67 shunts a small
amount of meter current and is adjusted for proper full
scale meter deflection in the voltage ranges.

Figure 4-3. Meter Circuit, Simplified Schematic

METER switch S2C shunts R69 in position 1 (the low
voltage range). Thus, in the low voltage range the meter
receives 10 times the amount of current that it receives
in the high voltage range, for the same power supply
output.

4-32 With METER switch S2 set to either current
position 3 or 4 (Figure 4-3B), the meter is connected
across the current sampling resistor R23. Current
calibrate potentiometer R65 is adjusted for proper full
scale meter deflection in the current ranges. METER
switch S2A shunts R64 in position 4 (the low current
range).

4-33 The meter is manufactured with a foolproof
movement, that is, it can withstand a current overload of
more than 10 times the maximum rated without injury.

4-4

SECTION V

A

B

LOAD LEAD

MONITOR HERE

OUTPUT TERMINAL

CURRENT SAMPLING TERMINALS

TO GROUNDED

TERMINAL OF

POWER SUPPLY

SAMPLING
RESISTOR

LOAD

TERMINALS

TO UNGROUNDED

TERMINAL OF

POWER SUPPLY

EXTERNAL

LOAD

MAINTENANCE
5-1 INTRODUCTION
5-2 Upon receipt of the power supply, the performance

check (Paragraph 5-10) should be made. This check is
suitable for incoming inspection. If a fault is detected in
the power supply while making the performance check
or during normal operation, proceed to the troubleshoot­ing procedures (Paragraph 5-27). After troubleshooting
and repair (Paragraph 5-37), perform any necessary
adjustments and calibrations (Paragraph 5-39). Before
returning the power supply to normal operation, repeat
the performance check to ensure that the fault has been
properly corrected and that no other faults exist. Before
doing any maintenance checks, turn-on power supply,
allow a half-hour warm-up, and read the general
information regarding measurement techniques
(Paragraph 5-3).

5-3 GENERAL MEASUREMENT TECHNIQUES
5-4 The measuring device must be connected across

the sensing leads of the supply or as close to the output
terminals as possible when measuring the output
impedance, transient response, regulation, or ripple of
the power supply in order to. achieve valid
measurements. A measurement made across the load
includes the impedance of the leads to the load and such
lead lengths can easily have an impedance several
orders of magnitude greater than the supply impedance,
thus invalidating the measurement.

5-5 The monitoring device should be connected to the
rear +S and –S terminals (see Figure 3-2) or as shown in
Figure 5-1. The performance characteristics should
never be measured on the front terminals if the load is
connected across the rear terminals. Note that when
measurements are made at the front terminals, the
monitoring leads are connected at A, not B, as shown in
Figure 5-1. Failure to connect the measuring device at A
will result in a measurement that includes the resistance
of the leads between the output terminals and the point
of connection.

5-6 For output current measurements, the current
sampling resistor should be a four-terminal resistor. The
four terminals are connected as shown in Figure 5-2. In
addition, the resistor should be of the low noise, low
temperature coefficient (less than 30 ppm/°C) type and
should be used at no more than 5% of its rated power so
that its temperature rise will be minimized.

Figure 5-2. Output Current Measurement Technique

Figure 5-1. Front Panel Terminal Connections

5-7 When using an oscilloscope, ground one terminal
of the power supply and then ground the case of the
oscilloscope to this same point. Make certain that the
case is not also grounded by some other means (power
line). Connect both oscilloscope input leads to the power
supply ground terminal and check that the oscilloscope
is not exhibiting a ripple or transient due to ground
loops, pick-up, or other means.

5-8 TEST EQUIPMENT REQUIRED
5-9 Table 5-1 lists the test equipment required to

perform the various procedures described in this
Section.

5-1

Table 5-1. Test Equipment Required

Type

Required

Characteristics

Use

Recommended

Model

Differential
Voltmeter

Sensitivity: 1mV full scale
(min.). Input impedance:
10 megohms (min.).

Measure DC voltages;
calibration procedures

3420 (See Note)

Variable
Voltage
Transformer

Range: 90-130 volts.
Equipped with voltmeter
accurate within 1 volt.

Vary AC input

---------------------------

AC Voltmeter

Accuracy: 2%. Sensitivity:
1mV full scale deflection
(min.).

Measure AC voltages and ripple

430 B

Oscilloscope

Sensitivity: 100µV/cm
Differential input.

Display transient response
waveforms

140 A plus

1400A plug in.

Oscillator

Range: 5 cps to 600Kc.
Accuracy: 2%

Impedance checks

200CD

DC Voltmeter

Accuracy: 1%. Input resistance:
20,000 ohms/volt (min.).

Measure DC voltages

412 A

Repetitive
Load Switch

Rate: 60 - 400 Hz, 2µsec
rise and fall time.

Measure transient response

See Figure 5-7

Resistive
Loads

Values: See Paragraph 5-14 and
Figure 5-4, ±5%, 75 watts.

Power supply resistors

---------------------------

Current
Sampling
Resistor

Value: See Figure 5-4,
1%, 40 watts, 20ppm,
4-Terminal.

Measure current; calibrate
meter

--------------------------­Resistor

1KΩ ±1%, 2 watt non-inductive

Measure impedance

---------------------------

Resistor

100 ohms, ±5%, 10 watt.

Measure impedance

---------------------------

Resistor

Value: See Paragraph 5-49,
±0.1%, ½ watt.

Calibrate programming current

--------------------------­Capacitor

500µF, 50wvdc

Measure impedance

---------------------------

Decade
Resistance
Box

Range: 0-500K.
Accuracy: 0.1% plus 1 ohm
Make-before-break contacts.

Measure programming
coefficients

---------------------------

5-2

5-10 PERFORMANCE TEST

POWER SUPPLY

UNDER TEST

NULL DETECTOR

LOAD

REFERENCE

VOLTAGE

SOURCE

R

Y

LOAD

RESISTOR

DIFFERENTIAL

VOLTMETER

POWER SUPPLY

UNDER TEST

R

X

CURRENT
SAMPLING
RESISTOR

G

MODEL NO.

RESISTANCE (OHMS)

RX

RY

6101A
6102A
6106A
6111A
6112A
6113A
6116A

1
2
5
1
2

0.5
5

19
78

495

19
78

4.5
495

5-11 The following test can be used as an incoming
inspection check and appropriate portions of the test can
be repeated either to check the operation of the
instrument after repairs or for periodic maintenance
tests. The tests are performed using a 115-VAC 60 cps.,
single phase input power source. If the correct result is
not obtained for a particular check, do not adjust any
controls; proceed to troubleshooting (Paragraph 5-27).

NOTE

A satisfactory substitute for a differential voltmeter is to
arrange a reference voltage source and null detector as
shown in Figure 5-3. The reference voltage source is
adjusted so that the voltage difference between the
supply being measured and the reference voltage will
have the required resolution for the measurement being
made. The voltage difference will be a function of the
null detector that is used. Examples of satisfactory null

detectors are: 419 A null detector, a DC coupled
oscilloscope utilizing differential input, or a 50 mV
meter movement with a 100 division scale. For the
latter, a 2 mV change in voltage will result in a meter
deflection of four divisions.

5-12 RATED OUTPUT AND METER ACCURACY
5-13 Voltage. Proceed as follows:

a. Connect load resistor across rear output

terminals of. supply for full load output. Resistor
value to be as follows:

Model No. 6101A 6102A 6106A 6111A 6112A
Resistance 20Ω 80Ω 500Ω 20Ω 80Ω
Model No. 6113A 6116A
Resistance 5Ω 500Ω

b. Connect differential voltmeter across +S and

–S terminals of supply observing correct polarity.

c. Set METER switch to highest voltage range

and turn on supply.

d. Adjust VOLTAGE controls until front panel

meter indicates exactly the maximum rated output
voltage.

e. Differential voltmeter should indicate

maximum rated output voltage within ±2%.
5-14 Current. Proceed as follows:

a. Connect test setup shown in Figure 5-4.
b. Turn CURRENT controls fully clockwise.
c. Set METER switch to highest current range

and turn on supply.

d. Adjust VOLTAGE controls until front panel

meter indicates exactly the maximum rated output
current.

e. Differential voltmeter should read 1.0 ± 0.02

V dc.

Figure 5-3. Differential Voltmeter

Substitute Test Setup

CAUTION

Care must be exercised when using an electronic null
detector in which one input terminal is grounded to
avoid ground loops and circulating currents.

Figure 5-4. Output Current, Test Setup

5-3

5-1 LOAD REGULATION (Front Terminals)

MODEL NO.

RESISTANCE (OHMS)

RX

RY

6101A
6102A
6106A
6111A
6112A
6113A
6116A

1
2
5
1
2

0.5
5

19
78

495

19
78

4.5

495

POWER SUPPLY

UNDER TEST

OSCILLOSCOPE

140A

G

R

Y

R

X

LOAD RESISTORS

1[

!!

POWER SUPPLY

UNDER TEST

DIFFERENTIAL

VOLTMETER

G

R

Y

R

X

5-16 To check constant voltage load regulation,
proceed as follows:

a. Connect test setup as shown in Figure

5-5.

b. Turn CURRENT controls fully clockwise.
c. Set METER switch to highest current range

and turn on supply.

d. Adjust VOLTAGE controls until front panel

meter indicates exactly the maximum rated output
voltage.

e. Read and record voltage indicated on

differential voltmeter.

f. Disconnect load resistors.
g. Reading on differential voltmeter should not

vary from reading recorded in step e by more than the
following:
Model No. 6101A 6102A 6106A 6111A
Variation (mvdc) 0.8 0.75 1.2 0.8
Model No. 6112A 6113A 6116A
Variation (mvdc) 0.75 1.2 1.2

d. Adjust variable auto transformer for 105

VAC input.

e. Set METER switch to highest voltage range

and turn on supply.

f. Adjust VOLTAGE controls until front panel

meter indicates exactly the maximum rated output
voltage.

g. Read and record voltage indicated on

differential voltmeter.

h. Adjust variable auto transformer for 125

VAC input.

i. Reading on differential voltmeter should not

vary from reading recorded in step g by more than the
following:
Model No. 6101A 6102A 6106A 6111A
Variation (mvdc) 0.2 0.4 1 0.2
Model No. 6112A 6113A 6116A
Variation (mvdc) 0.4 0.1 1

5-19 RIPPLE AND NOISE
5-20 To check the ripple and noise, proceed as follows:

5-17 LINE REGULATION (Front Terminals)
5-18 to check the line regulation, proceed as

follows:

a. Connect variable auto transformer between

input power source and power supply power input.

b. Turn CURRENT controls fully clockwise.
c. Connect test setup shown in Figure 5-5.

a. Retain test setup used for previous line

regulation test except connect oscilloscope across output
terminals as shown in Figure 5-6.

b. Adjust variable auto transformer for 125

VAC input.

c. Set METER switch to highest current

range.

d. Turn CURRENT controls fully clockwise

and adjust VOLTAGE controls until front panel meter
indicates exactly the maximum rated output voltage.

e. Oscilloscope should indicate 100µV

peak-to-peak or less.

Figure 5-5. Load Regulation, Test Setup

5-4

Figure 5-6. Ripple and Noise, Test Setup

5-21 TRANSIENT RECOVERY TIME

R

Y

POWER SUPPLY

UNDER TEST

R

X

OSCILLOSCOPE

140A

G

1µF

400V

5Ω 5W

(NOTE 3)

CONTACT PROTECTION

NETWORK

11K

3W

25K

2W

115V

60 HZ

NOTE 2

REPETITIVE LOAD

SWITCH (NOTE 1)

NOTES:

1. THIS DRAWING SHOWS
A SUGGESTED METHOD
OF BUILDING A LOAD
SWITCH. HOWEVER,
OTHER METHODS COULD
BE USED; SUCH AS A
TRANSISTOR SWITCHING
NETWORK. MAXIMUM
LOAD RATINGS OF LOAD
SWITCH ARE: 5 AMPS,
500V, 250W (NOT 2500W).

2. USE MERCURY RELAY;
CLARE TYPE HGP 1002 OR
W. E. TYPE 276B

3. USE WIRE WOUND RESISTOR

MODEL NO.

RESISTANCE (OHMS)

RX

RY

6101A
6102A
6106A
6111A
6112A
6113A
6116A

1
2
5
1
2

0.5
5

19
78

495

19
78

4.5

495

50µsec

LOADING UNLOADING

50µsec

10mV

10mV

VOLTMETER

403B

INDICATES E

o

VOLTMETER

403B

INDICATES E

in

POWER SUPPLY

UNDER TEST

OSCILLATOR

200CD

1K

100 OHM

500 MFD

G

5-22 To check the transient recovery time proceed as
follows:

a. Connect test setup shown in Figure 5-7.
b. Turn CURRENT controls fully clockwise.
c. Set METER switch to highest current

range and turn on supply.

d. Adjust VOLTAGE controls until front

panel meter indicates exactly the maximum rated
output voltage.

e. Close line switch on repetitive load switch

setup.

f. Adjust 25K potentiometer until a stable

display is obtained on oscilloscope. Waveform
should be within the tolerances shown in Figure 5-8
(output should return to within 10 mV of original
value in less than 50 microseconds).

Figure 5-8. Transient Recovery Time, Waveforms
5-23 OUTPUT IMPEDANCE
5-24 To check the output impedance, proceed as

follows:

a. Connect test setup as shown in Figure 5-9.

Figure 5-7. Transient Recovery Time, Test Setup

NOTE

If the unloading waveform is unobtainable, use
a smaller value capacitor in the contact
protection network illustrated in Figure 5-7.

Figure 5-9. Output Impedance, Test Setup
b. Set METER switch to highest voltage range,

turn CURRENT controls fully clockwise, and turn on
supply.

c. Adjust VOLTAGE controls until front panel

meter reads 20 volts (10 volts for Model 6113A
supplies).

d. Set AMPLITUDE control on Oscillator to 10

volts (Ein), and FREQUENCY control to 10 cps.

e. Record voltage across output terminals of the

power supply (Eo) as indicated on AC voltmeter.

f. Calculate the output impedance by the

following formula:



 









Eo = rms voltage across power supply output

terminals.
R = 1000
Ein = 10 volts

5-5

g. The output impedance (Z

Step

Meter

Common

Meter

Positive

Normal

Indication

If Indication Abnormal, Take This Action

1

+S

30

6.2 ± 0.3vdc

Check 12.4 volt bias or VR1

2

34

+S

9.4± 0.4vdc

Check 12.4 volt bias or VR2

3

+S

16

12.4± 1.0vdc

Check Q12-Q15, CR24, CR25, C16, T1

than 0.002 ohm.

should be less

out)

h. Using formula of step f, calculate output

impedance at frequencies of 100cps, 1Kc, and 500Kc.
Values should be less than 0.02 ohm, 0.5 ohm, and 3
ohms, respectively.

5-25 CURRENT LIMIT
5-26 To check the current limit circuit, proceed as

follows:

a. Set the METER switch to the highest

voltage range.

b. Turn the VOLTAGE controls fully clock-

wise.

c. Turn the CURRENT control fully counter-

clockwise.

d. The voltage should reduce to zero.
e. Connect a short circuit across the output

terminals.

f. Set the METER switch to the highest current

range.

g. Turn the CURRENT control fully clockwise.
h. The current should increase to, but not

exceed the following:
Model 6101A 6102A 6106A 6111A
Current Limit (A) 1.05 0.52 0.21 1.05
Model 6112A 6113A 6116A
Current Limit (A) 0.52 2.1 0.21

5-27 TROUBLESHOOTING
5-28 Components within Hewlett-Packard power

supplies are conservatively operated to provide
maximum reliability. In spite of this, parts within a
supply may fail. Usually the instrument must be
immediately repaired with a minimum of ''down time"
and a systematic approach as outlined in succeeding
paragraphs can greatly simplify and speed up the repair.

5-29 TROUBLE ANALYSIS
5-30 General. Before attempting to trouble shoot this

instrument, ensure that the fault is with the instrument
and not with an associated circuit.

The performance test (Paragraph 5-10) enables this to be
determined without having to remove the instrument
from the cabinet.

5-31 Once it is determined that the power supply is at
fault, check for obvious troubles such as open fuse, a
defective power cable, or an input power failure. Next,
remove the top and bottom covers (each held by four
retaining screws) and inspect for open connections,
charred components, etc. If the trouble source cannot be
detected by visual inspection, follow the detailed
procedure outlined in succeeding paragraphs. Once a
defective component has been located (by means of
visual inspection or trouble analysis) correct it and
reconduct the performance test. If a component is
replaced, refer to the repair and replacement, and
adjustment and calibration paragraphs in this section.

5-32 A good understanding of the principles of
operation is a helpful aid in troubleshooting, and it is
recommended that the reader review Section IV of the
manual before attempting to troubleshoot the unit in
detail. Once the principles of operation are understood,
logical application of this knowledge used in
conjunction with the normal voltage readings shown on
the schematic and the additional procedures given in the
following paragraphs should suffice to isolate a fault to
a component or small group of components. The normal
voltages shown on the schematic are positioned adjacent
to the applicable test points (identified by encircled
numbers on the schematic and printed wiring boards).
Additional test procedures that will aid in isolating
troubles are as follows:

a. Reference circuit check (Paragraph 5-34). This

circuit provides critical operating voltages for the supply
and faults in the circuit could affect the overall operation
in many ways.

b. Feedback loop checks (Paragraph 5 -35).
c. Procedures for isolating common troubles

(Paragraph 5-36).
5-33 The test points referred to throughout the

following procedures are identified on the schematic
diagram by encircled numbers.

Table 5-2. Reference Circuit Troubleshooting

5-6

5-34 Reference Circuit

Step

Measure (-) (+)

Response

Probable Cause

1

Voltage between +S and A5

a. +0.6V

b. 0V or negative

a. Open strap between A8 and –S.

R20 open.

b. Proceed to Step 2.

2

Voltage between 13 and 14

a. More negative than –0.1V.

b. Within ±0.1V of 0V.

c. More positive than +0.1V.

a. Q1A shorted, R1, R2 open.

b. C6, C3 shorted.

c. Proceed to Step 3.

3

Voltage between +S and 25

a. More negative than +0.5V.

b. More positive than +0.5V.

a. Q7, C8, CR9, R32 shorted.

Q8, R23, R31, R33 open.

b. Proceed to Step 4.

4

Voltage between +S and 27

a. 0V to +0.2V.
b. More positive than 0.2V.

a. Q10 or Q11 shorted.
b. Q9 open, R35 shorted.

Step

Measure (–) (+)

Response

Probable Cause

1

Disable Q5 by
disconnecting CR8

a. Normal output voltage.

b. Low output voltage

a. Current limit circuit faulty,

check CR8, Q5, and R26 for
short.

b. Reconnect CR8 and proceed to

Step 2

2

Voltage between +S and A5

a. More negative than +0.1V.

b. +0.1V to +0.8V.

a. C4 shorted, R17, R18 open.

b. Proceed to step 3.

3

Voltage between 13 and 14

a. More positive than +0.1V.

b. More negative than –0.1V.

a. Q1A open. R1, R2 open.

b. Proceed to step 4.

d. Proceed as instructed in Table 5-2.

a. Make an ohmmeter check to be certain that

neither the positive nor negative output terminal is
grounded.

b. Turn front-panel VOLTAGE and CURRENT

controls fully clockwise (maximum).

c. Turn-on power supply (no load connected).

Table 5-3. High Output Voltage Troubleshooting

5-35 Feedback Circuit. Generally, malfunction of the
feedback circuit is indicated by high or low output
voltages. If one of these situations occurs, disconnect
the load and proceed as instructed in Table 5-3 or Table
5-4.

Table 5-4. Low Output Voltage Troubleshooting

5-7

Table 5-4. Low Output Voltage Troubleshooting (Continued)

4

Voltage between +S and 25

a. More positive than +0.6V.

b. More negative than +0.5V.

a. Q8 shorted, Q7 open, C10

shorted.*

b. Proceed to Step 5.

5

Voltage between +S and 27

a. More positive than 1V.
b. More negative than 0V.

a. Q10, Q11 open. R38 shorted.
b. Q9, CR10, CR11, CR12, C9

shorted.
CR13, CR14, CR15 open. R35
open.

Symptom

Checks and Probable Causes

High ripple

a. Check operating setup for ground loops.
b. If output floating, connect 1µF capacitor between output and ground.
c. Ensure that supply is not crossing over to current limit mode under loaded

conditions. Check for low voltage across C19.

Poor line regulation

a. Check reference circuit (Paragraph 5-34)

Poor load regulation
(Constant Voltage)

a. Measurement technique. (Paragraph 5-15)
b. Check reference circuit (Paragraph 5-34)
c. Ensure that supply is not going into current limit. Check current limit

circuit

Oscillates

a. Constant Voltage

Operation

b. Current Limit

Operation

a. C6, R30, C3, R9, C7, R34, C8, or C9 open

b. C5, R29, or C9 open

Poor Stability
(Constant Voltage)

a. Check ±6.2Vdc reference voltages (Paragraph 5-34).
b. Noisy programming resistor R20.
c. CR1, CR2 leaky.
d. Check R10, R11, VR1 for noise or drift.
e. Stage Q1 defective.

*

Check Q9 and CR9 for damage

Table 5-5. Common Troubles

5-36 Common Troubles. Table 5-5 lists the
symptoms, checks, and probable causes for common
troubles.

5-37 REPAIR AND REPLACEMENT
5-38 Before servicing a printed wiring board, refer to

Figure 5-10. Section VI of this manual contains a list of

replaceable parts. Before replacing a semiconductor
device, refer to Table 5-6 which lists the special
characteristics of selected semiconductors. If the device
to be replaced is not listed in Table 5-6, the standard
manufacturers part number listed in Section VI is
applicable. After replacing a semiconductor device,
refer to Table 5-7 for checks and adjustments that may
be necessary.

5-8

APPLY

SOLDER

Excessive heat or pressure can lift the copper strip from the board. Avoid damage by using a low
power soldering iron (50 watts maximum) and following these instructions. Copper that lifts off the
board should be cemented in place with a quick drying acetate base cement having good electrical
insulating properties.

A break in the copper should be repaired by soldering a short length of tinned copper wire across the
break.

Use only high quality rosin core solder when repairing etched circuit boards. NEVER USE PASTE
FLUX. After soldering, clean off any excess flux and coat the repaired area with a high quality
electrical varnish or lacquer.

When replacing components with multiple mounting pins such as tube sockets, electrolytic
capacitors, and potentiometers, it will be necessary to lift each pin slightly, working around the
components several times until it is free.

WARNING: If the specific instructions outlined in the steps below regarding etched circuit boards
without eyelets are not followed, extensive damage to the etched circuit board will result.

1. Apply heat sparingly to lead of component to
be replaced. If lead of component passes through
an eyelet in
the circuit
board, apply
heat on
component
side of
board. If
lead of
component does not pass through an eyelet,
apply heat to conductor side of board.

2. Reheat solder in vacant eyelet and quickly
insert a small awl to clean inside of hole. If hole
does not
have an
eyelet,
insert awl
or a #57
drill from
conductor
side of
board.

3. Bend clean tinned lead on new part and
carefully insert
through eyelets or
holes in board.

4. Hold part against board (avoid overheating)
and solder leads.
Apply heat to compo­nent leads on correct
side of board
as explained
in step 1

In the event that either the circuit board has been damaged or the conventional method is
impractical, use method shown below. This is especially applicable for circuit boards without
eyelets.

1. Clip leads as shown below.

CLIP

HERE

2. Bend protruding leads upward. Bend lead of
new

component around
protruding
lead. Apply
solder using a pair of long nose pliers as a heat
sink.

This procedure is used in the field only as an alternate means of repair. It is not used within the
factory.

CONDUCTOR

SIDE

Figure 5-10. Servicing Printed Wiring Boards

5-9

Table 5-6. Selected Semiconductor Characteristics

Reference

Designator

Characteristics

stock No.

Suggested

Replacement

Q1

Diff. Amp. NPN

1854-0221

2N4045

Q2, Q3, Q9,

Q10, Q13-Q15

SS NPN Silicon

1854-0027

2N2714

CR1, CR2, CR4,

CR8, CR9,
CR16, CR31

Diode, Silicon

1901-0033

1N485B Sylvania

CR10, CR13,

CR20

Diode, Sil, 2.4V @
100mA

1901-0460

1N4830 G.E.

CR19, CR23

Rect. Sil. Stabistor
200mA, 10prv

1901-0461

1N4828 G.E.

CR24-CR29,

CR30B,
CR32-CR34

Rect. Silicon
500mA, 200prv

1901-0026

1N3253 G.E.

Reference

Function

Check

Adjust

Ql, Q2, Q3,

Q7, Q8, Q9

Voltage error amplifier

Voltage load regulation
Remote programming

R14

Q10, Q11,

Series Regulator

Voltage load regulation

Q5

Current Limit Amplifier

Current limit operation

Q12,13,14,

15

Reference Circuit Amplifier

+6.2V line regulation

Q16

Oven Control Pulse Generator

Oven temperature setting

R56

CR1,2

Protection Diode

Voltage-load regulation

CR4,10,13

Forward Bias Regulators

Voltage across each diode

0.6 to 0.85 volts

CR8

Current Limit Coupling Diode

Current limit operation

CR9

Overshoot suppressor diode

Turn-on overshoot

CR16

Overshoot suppressor diode

Turn-on overshoot

CR19

Reference Circuit Start-up diode

Reference circuit operation

CR24, 25

Rectifier

Voltage on C16

CR26, 27, 28

Rectifier

Voltage on C17

Table 5-7. Checks and Adjustments After Replacement of Semiconductor Devices

5-10

Table 5-7. Checks and Adjustments After Replacement of Semiconductor Devices (Continued)

CR29,30,33,
34

Rectifier

Voltage on C19
CR31

Oven SCR

Oven Functioning

CR32

Protection diode

VR1

+6.2 Voltage Reference

Remote Programming
Coefficient, zero crossing

R17,R116
R14

VR2

-9.4 Voltage Reference

Remote Prog, Coefficient
zero crossing

R16
R14

MI, R64, or R66

Current meter cal.
Voltage meter cal.

R65
R67

Adjustment or Calibration

Paragraph

Control Device

Meter Zero

5-41

Pointer

Voltmeter Tracking

5-43

R67

Ammeter Tracking

5-45

R65

Zero Volt Programming Accuracy

5-47

R6 or R8

Programming Current Level

5-49

R13

5-39 ADJUSTMENT AND CALIBRATION
5-40 Adjustment and calibration may be required after

performance testing, troubleshooting, or repair and
replacement.

Table 5-8. Calibration Adjustment Summary

5-41 METER ZERO
5-42 Proceed as follows to zero meter:

a. Turn off instrument (after it has reached normal
operating temperatur9) and allow 30 seconds for all
capacitors to discharge.

Perform only those ad justments that affect the operation
of the faulty circuit and no others. Table 5-8 summarizes
the adjustments and calibrations contained in the fol­lowing paragraphs.

5-43 VOLTMETER TRACKING
5-44 To calibrate voltmeter tracking, proceed as

follows:

a. Connect differential voltmeter across supply,

observing correct polarity.

b. Insert sharp pointed object (pen point or awl)
into the small indentation near top of round black plastic
disc located directly below meter face.

c. Rotate plastic disc clockwise (cw) until meter
reads zero, then rotate ccw slightly in order to free
adjustment screw from meter suspension. If pointer
moves, repeat steps b and c.

b. Set METER switch to highest voltage range
and turn on supply. Adjust VOLTAGE control until
differential voltmeter reads exactly the maximum rated
output voltage.

c. Adjust R67 until front panel meter also
indicates maximum rated output voltage.

5-11

5-45 AMMETER TRACKING
5-46 To calibrate ammeter tracking proceed as follows:

a. Connect the supply under test for remote
resistance programming as illustrated in Figure 3-3.

a. Connect test setup shown on Figure 5-4.
b. Turn VOLTAGE control fully clockwise and

set METER switch to highest current range.

c. Turn on supply and adjust CURRENT controls

until differential voltmeter reads 1.0 Vdc.

d. Adjust R65 until front panel meter indicates

exactly the maximum rated output current.
5-47 CONSTANT VOLTAGE PROGRAMMING

CURRENT

5-48 Zero Volt Programming Accuracy. To calibrate
the zero volt programming accuracy, proceed as
follows:

a. Connect differential voltmeter between +S and

-S terminals.
b. Short voltage controls by connecting jumper

between terminals A5 and -S.

c. Rotate CURRENT control fully clockwise and

turn on supply.

d. Adjust zero crossing potentiometer R14 until

the meter indicates zero volts.
5-49 Programming Current Level. To calibrate the

constant voltage programming current level, proceed as
follows:

b. Connect a 0.1%, 2-watt programming resistor
between terminals A4 and -S on rear barrier strip.
Resistor value to be as follows:

Model 6101A 6102A 6106A 6111A
Resistance (ohms) 20K 40K 100K 20K
Model 6112A 6113A 6116A
Resistance (ohms) 40K 10K 100K

c. Connect a differential voltmeter between -S
and +5 and turn on the supply.

d. Adjust potentiometer R16 until differential
voltmeter indicates the maximum rated output voltage of
the supply. If the range of R16 is not sufficient to adjust
the output voltage within tolerance proceed to step e.

e. Set potentiometer R16 to the center of its
range.

f. Replace R17 with a resistance decade initially
set for 300 ohms.

g. Adjust the resistance decade until the
differential voltmeter indicates the maximum rated
output voltage of the supply.

h. Replace the decade resistance with a resistor
whose value is as close to the resistance decade as
possible.

i. Readjust R16 until the differential voltmeter
indicates the maximum rated output voltage of the
supply.

5-12

SECTION VI

A = assembly
B = blower (fan)
C = capacitor
CB = circuit breaker
CR = diode
DS = device, signal-

ing (lamp)

E = miscellaneous

electronic part
F = fuse
J = Jack, jumper
K = relay
L = inductor
M = meter

P = plug
Q = transistor
R = resistor
S = switch
T = transformer
TB = terminal block
TS = thermal switch

V = vacuum tube,

neon bulb,

photocell, etc.
VR = zener diode
X = socket
Z = integrated cir-

cuit or network

A = ampere
ac = alternating

current
assy. = assembly
bd = board
bkt = bracket
°C = degree

Centigrade
cd = card
coef = coefficient
comp = composition
CRT = cathode-ray

tube
CT = center-tapped
dc = direct current
DPDT = double pole,

double throw
DPST = double pole,

single throw
Elect = electrolytic
Encap = encapsulated
F = farad
°F = degree

Fahrenheit
Fxd = fixed
Ge = germanium
H = Henry
Hz = Hertz
IC = integrated

circuit
ID = inside diameter
incnd = incandescent
k = kilo = 103
m = milli = 10-3
M = mega = 106
µ = micro = 10-6
met. = metal

Mfr = manufacturer
Mod. = modular or

modified
Mtg = mounting
N = nano = 10-9
NC = normally closed
NO = normally open
NP = nickel-plated
Ω = ohm
obd = order by

description
OD = outside

diameter
Pico = 10

-12

P. C. = printed circuit
Pot. = potentiometer
p-p = peak-to-peak
ppm = parts per

miliion
pvr = peak reverse

voltage
rect = rectifier
rms = root mean

square
Si = silicon
SPDT = single pole,

double throw
SPST = single pole,

single throw
SS = small signal
T = slow-blow
tan. = tantalum
Ti = titanium
V = volt
var = variable
ww = wirewound
W = Watt

REPLACEABLE PARTS
6-1 INTRODUCTION
6-2 This section contains information for ordering

replacement parts. Table 6-4 lists parts in alpha numeric
order by reference designators and provides the
following information:

a. Reference Designators. Refer to Table 6-1.
b. Description. Refer to Table 6-2 for

abbreviations.

c. Total Quantity' Q). Given only the first time the
part number is listed except in instruments containing
many sub-modular assemblies, in which case the TQ
appears the first time the part number is listed in each
assembly.

d. Manufacturer's Part Number or Type.

e. Manufacturer's Federal Supply Code Number.
Refer to Table 6-3 for manufacturer's name and address.

f. Hewlett-Packard Part Number.

g. Recommended Spare Parts Quantity (RS) for
complete maintenance of one instrument during one
year of isolated service.

h. Parts not identified by a reference designator
are listed at the end of Table 6-4 under Mechanical
and/or Miscellaneous. The former consists of parts
belonging to and grouped by individual assembles; the
latter consists of all parts not immediately associated
with an assembly.

6-3 ORDERING INFORMATION
6-4 To order a replacement part, address order or

inquiry to your local Hewlett-Packard sales office (see
lists at rear of this manual for addresses). Specify the
following information for each part: Model, complete
serial number, and any Option or special modification
(1) numbers of the instrument; Hewlett-Packard part
number; circuit reference designator; and description.
To order a part not listed in Table 6-4, give a complete
description of the part, its function, and its location.

Table 6-1. Reference Designators (Continued)

Table 6-2. Description Abbreviations

Table 6-1. Reference Designators

6-1

CODE
NO.

MANUFACTURER ADDRESS

CODE
NO.

MANUFACTURER ADDRESS

00629
00656
00853

01121
01255
01281

01295

01686
01930
02107
02114
02606
02660
02735

03508
03797

03877
03888
04009
04072

04213
04404
04713
05277
05347

05820
06001

06004
06486
06540
06555
06666

06751
06776

06812
07137

EDY Sales Co., Inc. Jamaica, N. Y.
Aerovox Corp. New Bedford, Mass,
Sangamo Electric Co

S. Carolina Div. Pickens, S.C.
Allen Bradley Co. Milwaukee, Wis.
Litton Industries, Inc Beverly Hills, Calif.
TRW Semiconductors, Inc.
Lawndale, Calif.
Texas Instruments, Inc.

Semiconductor-Components Div,
Dallas, Texas
RCL Electronics, Inc. Manchester, N.H.
Amerock Corp. Rockford, Ill.
Sparta Mfg, Co. Dover, Ohio
Ferroxcube Corp. Saugerties, N.Y.
Fenwal Laboratories Morton Grove, Ill.
Amphenol Corp. Broadview, Ill.
Radio Corp. of America, Solid State

and Receiving Tube Div. Somerville, N.

J.
G.E. Semiconductor Products Dept,
Syracuse, N.Y.
Eldema Corp. Compton, Calif.
Transitron Electronic Corp.
Wakefield, Mass.
Pyrofilm Resistor Co, Inc.
Cedar Knolls, N.J.
Arrow, Hart and Hegeman Electric Co.
Hartford, Conn.
ADC Electronics, Inc. Harbor City, Calif.
Caddell & Burns Mfg, Co. Inc.
Mineola, N.Y.
*Hewlett-Packard Co. Palo Alto Div.
Palo Alto, Calif.
Motorola Semiconductor Prod. Inc.
Phoenix, Arizona
Westinghouse Electric Corp.

Semiconductor Dept. Youngwood, Pa.
Ultronix, Inc, Grand Junction, Colo,
Wakefield Engr. Inc. Wakefield, Mass.
General Elect. Co. Electronic

Capacitor & Battery Dept. Irmo, S.C.
Bassik Div, Stewart-Warner Corp.
Bridgeport, Conn.
IRC Div. of TRW Inc.

Semiconductor Plant Lynn, Mass.
Amatom Electronic Hardware Co. Inc.
New Rochelle, N.Y.
Beede Electrical Instrument Co.
Penacook, N.H.
General Devices Co. Inc.Indianapolis, Ind.
Semcor Div. Components, Inc.
Phoenix, Arizona
Robinson Nugent, Inc. New Albany, Ind.
Torrington Mfg, Co., West Div.
Van Nuys, Calif.
Transistor Electronics Corp.

Minneapolis, Minn.

07138
07263

07387
07397

07716
07910
07933

08484
08530
08717
08730
08806

08863
08919
09021

09182
09213
09214
09353

09922
11115

11236
11237

11502
11711
12136

12615
12617
12697
13103
14493

14655
14936
15801

16299

Westinghouse Electric Corp.

Electronic Tube Div. Elmira, N. Y.
Fairchild Camera and Instrument
Corp. Semiconductor Div.
Mountain View, Calif.
Birtcher Corp., The Los Angeles, Calif.
Sylvania Electric Prod. Inc.

Sylvania Electronic Systems

Western Div. Mountain View, Calif.
IRC Div. of TRW Inc, Burlington Plant
Burlington, Iowa
Continental Device Corp.
Hawthorne, Calif.
Raytheon Co. Components Div,

Semiconductor Operation
Mountain View, Calif.
Breeze Corporations, Inc. Union, N.J.
Reliance Mica Corp. Brooklyn, N.Y.
Sloan Company, The Sun Valley, Calif.
Vemaline Products Co. Inc.Wyckoff, N.J.
General Elect. Co. Minia-

ture Lamp Dept. Cleveland, Ohio
Nylomatic Corp. Norrisville, Pa.
RCH Supply Co. Vernon, Calif.
Airco Speer Electronic Components
Bradford, Pa.
*Hewlett-Packard Co, New Jersey Div,
Berkeley Heights, N.J.
General Elect. Co. Semiconductor

Prod. Dept. Buffalo. N.Y.
General Elect. Co. Semiconductor

Prod, Dept, Auburn, N.Y.
C & K Components Inc. Newton, Mass.
Burndy Corp. Norwalk, Conn.
Wagner Electric Corp.

Tung-Sol Div. Bloomfield, N.J.
CTS of Berne, Inc. Berne, Ind.
Chicago Telephone of Cal. Inc.
So. Pasadena, Calif.
IRC Div. of TRW Inc. Boone Plant
Boone, N.C.
General Instrument Corp

Rectifier Div. Newark, N. J.
Philadelphia Handle Co. Inc.Camden, N.J.
U.S. Terminals, Inc. Cincinnati, Ohio
Hamlin Inc. Lake Mills, Wisconsin
Clarostat Mfg. Co. Inc. Dover, N.H.
Thermalloy Cp, Dallas, Texas
*Hewlett-Packard Co. Loveland Div.
Loveland, Colo.
Cornell-Dubilier Electronics Div.

Federal Pacific Electric Co.
Newark, N.J.
General Instrumert Corp. Semicon-

ductor Prod. Group Hicksville, N.Y.
Fenwal Elect. Framingham, Mass.
Corning Glass Works, Electronic

Components Div. Raleigh, N.C.

*Use Code 28480 assigned to Hewlett-Packard Co., Palo Alto, California

Table 6-3. Code List of Manufacturers

6-2

CODE
NO.

MANUFACTURER ADDRESS

CODE
NO.

MANUFACTURER ADDRESS

16758
17545
171303

17870
18324

19315
19701
21520
22229
22753

23936
24446
24455

24655
24681

26982
27014

28480
28520
28875

31514
31827

33173
35434
37942
42190
4333'.

44655
46364

47904
49956
55026

56289
58474
58849

59730
61637
63743

Delco Radio Div, of General Motors Corp.
Kokomo, Ind,
Atlantic Semiconductors, Inc.
Asbury Park, N. J.
Fairchild Camera and Instrument Corp

Semiconductor Div, Transducer Plant
Mountain View, Calif.
Devon Div. Thomas A. Edison Industries

McGraw-Edison Co, Orange, 14. I.
Signetics Corp. Sunnyvale, Calif.
Bendix Corp. The Navigation and

Control Div, Tetelboro, N. J.
Electra/Midland Corp.
Mineral Wells, Texas
Fansteel Metallurgical Corp.
No. Chicago, Ill.
Union Carbide Corp. Electronics Div,
Mountain View, Calif.
UID Electronics Corp. Hollywood, Fla.
Pamotor, Inc, Pampa, Texas
General Electric Co. Schenectady, N.Y.
General Electric Co. Lamp Div. of Con-

sumer Prod, Group
Nela Park, Cleveland, Ohio
General Radio Co. West Concord, Mass.
LTV Electrosystems Inc Memcor/Com­ponents Operations Huntington, Ind.
Dynacool Mfg. Co. inc. Saugerties, N. Y.
National Semiconductor Corp.
Santa Clara, Calif.
Hewlett-Packard Co. Palo Alto, Calif.
Heyman Mfg. Co. Kenilworth, N. J.
IMC Magnetics Corp.

New Hampshire Div, Rochester, N. H.
SAE Advance Packaging, Inc.
Santa Ana, Calif.
Budwig Mfg. Co. Ramona, Calif.
G.E. Co, Tube Dept. Owensboro, Ky.
Lectrohm, Inc. Chicago, Ill.
P.R. Mallory & Co. Inc, Indianapolis, Ind.
Muter Co. Chicago, Ill.
New Departure-Hyatt Bearings Div,

General Motors Corp. Sandusky, Ohio
Ohmite Manufacturing Co. Skokie, Ill.
Penn Engr„ and Mfg. Corp.
Doylestown, Pa.
Polaroid Corp. Cambridge. Mass.
Raytheon Co. Lexington, Mass,
Simpson Electric Co. Div. of American

Gage and Machine Co. Chicago, Ill.
Sprague Electric Co. North Adams, Mass,
Superior Electric Co. Bristol, Conn.
Syntron Div. of FMC Corp.
Homer City, Pa.
Thomas and Betts Co. Philadelphia, Pa.
Union Carbide Corp. New York, N.Y.
Ward Leonard Electric Co.
Mt. Vernon, N.Y.

70563
70901
70903
71218
71279

71400
71450

71468
71590
71700
71707

71744
71785
71984

72136
72619

72699
72765
72962

72982
73096
73138

73168
73293

73445
73506
73559

73734
74193
74545
74868

74970
75042
75183

75376
75382
75915
76381

76385
76487

76493

Amperite Co. Inc. Union City, N.J.
Beemer Engrg, Co. Fort Washington, Pa.
Belden Corp. Chicago, Ill.
Bud Radio, Inc. Willoughby, Ohio
Cambridge Thermionic Corp.
Cambridge, Mass.
Bussmann Mfg, Div. of McGraw &

Edison Co. St, Louis, Mo.

CTS Corp. Elkhart, Ind.
I.T.T. Cannon Electric Inc.
Los Angeles, Calif,
Globe-Union Inc.

Centralab Div. Milwaukee, Wis.

General Cable Corp, Cornish

Wire Co. Div, Williamstown, Mass.

Coto Coil Co. Inc. Providence, R.I.
Chicago Miniature Lamp Works
Chicago, Ill.
Cinch Mfg. Co. and Howard

B. Jones Div. Chicago, Ill.

Dow Coming Corp. Midland, Mich.
Electro Motive Mfg, Co. Inc.
Willimantic, Conn.
Dialight Corp. Brooklyn, N.Y.
General Instrument Corp. Newark, N.J.
Drake Mfg, Co. Harwood Heights, Ill.
Elastic Stop Nut Div. of

Amerace Esna Corp. Union, N.J.

Erie Technological Products Inc. Erie, Pa.
Hart Mfg. Co. Hartford, Conn.
Beckman Instruments Inc,

Helipot Div. Fullerton, Calif.

Fenwal, Inc. Ashland, Mass.
Hughes Aircraft Co. Electron

Dynamics Div. Torrance, Calif.

Amperex Electronic Corp.
Hicksville, N.Y.
Bradley Semiconductor Corp,
New Haven, Conn.
Carling Electric, Inc. Hartford, Conn,
Federal Screw Products, Inc. Chicago, Ill.
Heinemann Electric Co. Trenton, N.J.
Hubbell Harvey Inc. Bridgeport, Conn.
Amphenol Corp. Amphenol RF Div.
Danbury, Conn.
E. F. Johnson Co. Waseca, Minn.
IRC Div. of TRW, Inc. Philadelphia, Pa.
*Howard B. Jones Div. of Cinch

Mfg. Corp. New York, N.Y.

Kurz and Kasch, Inc. Dayton, Ohio
Kilka Electric Corp. Mt. Vernon, N.Y.
Litttefuse, Inc. Des Plaines, Ill.
Minnesota Mining and Mfg. Co.
St. Paul, Minn.
Minor Rubber Co. Inc. Bloomfield, N.J.
James Millen Mfg, Co, Inc.
Malden, Mass.
J. W. Mitier Co. Compton, Calif.

*Use Code 71785 assigned to Cinch Mfg. Co., Chicago Ill.

Table 6-3. Code List of Manufacturers (Continued)

6-3

CODE
NO.

MANUFACTURER ADDRESS

CODE
NO.

MANUFACTURER ADDRESS

76530
76854

77068
77122

77147
77221

77252
77342
77630
77764

78189
78452

78468
78526

78553
78584
79136
79307
79727

79963
80031

80294
81042

81073
81483

81751
82099

82142
82219

82389
82647

82866
82877
82893
83058
83186

83298
83330

83385
83501

Cinch City of Industry, Calif.
Oak Mfg. Co. Div, of Oak

Electro/Netics Corp. Crystal Lake, Ill.
Bendix Corp., Electrodynamics Div.
No. Hollywood, Calif.
Palnut Co. Mountainside, N.J.
Patton-MacGuyer Co. Providence, R.I.
Phaostron Instrument and Electronic Co.
South Pasadena, Calif.
Philadelphia Steel and Wire Corp.
Philadelphia, Pa.
American Machine and Foundry Co.

Potter and Brumfield Div, Princeton, Ind.
TRW Electronic Components Div.
Camden, N.J.
Resistance Products Co. Harrisburg, Pa.
Illinois Tool Works Inc. Shakeproof Div.
Elgin, Ill.
Everlock Chicago, Inc. Chicago, Ill.
Stackpole Carbon Co. St. Marys, Pa.
Stanwyck Winding Div. San Fernando

Electric Mfg. Co. Inc. Newourgh, N.Y.
Tinnerman Products, Inc. Cleveland, Ohio
Stewart Stamping Corp. Yonkers, N.Y.
Waldes Kohinoor, Inc. L.I.C., N.Y.
Whitehead Metals Inc. New York, N.Y.
Continental-Wirt Electronics Corp.
Philadelphia, Pa.
Zierick Mfg. Co. Mt. Kisco, N.Y.
Mepco Div. of Sessions Clock Co,
Morristown, N.J.
Bourns, Inc. Riverside, Calif.
Howard Industries Div. of Msl Ind. Inc.
Racine, Wisc.
Grayhill, Inc, La Grange, Ill.
International Rectifier Corp.
CI Segundo, Calif.
Columbus Electronics Corp. Yonkers, N.Y.
Goodyear Sundries & Mechanical Co. Inc.
New York, N. Y.
Airco Speed Electronic Components
Du Bois, Pa.
Sylvania Electric Products Inc.

Electronic Tube Div. Receiving

Tube Operations Emporium, Pa.
Switchcraft, Inc. Chicago, Ill
Metals and Controls Inc, Control

Products Group Attleboro, Mass.
Research Products Corp. Madison, Wis.
Rotron Inc. Woodstock, N.Y.
Vector Electronic Co. Glendale, Calif.
Garr Fastener Co. Cambridge, Mass.
Victory Engineering Corp.
Springfield, N.J.
Bendix Corp. Electric Power Div.
Eatontown, N.J.
Herman H. Smith, Inc. Brooklyn, N.Y.
Central Screw Co. Chicago, Ill.
Gavin Wire and Cable Div. of

Amerace Esna Corp. Brookfield, Mass.

83508
83594
83835

83877
84171

84411
86684

86838
87034

87216
875135

87929
88140

88245
90634

90763
91345

91418
91506
91637
91662
91929

92825
93332

93410
94144
94154
94222

95263
95354
95712

95987
96791

97464
97702
98291

98410
98978

99924

Grant Pulley and Hardware Co.
West Nyack, N.Y.
Burroughs Corp. Electronic

Components Div. Plainfield, N.J.

U. S. Radium Corp. Morristown, N.J.
Yardeny Laboratories, Inc.
New York, N.Y.
Arco Electronics, Inc. Great Neck, N.Y.
TRW Capacitor Div. Ogallala, Neb.
RCA Corp. Electronic Components
Harrison, N.J.
Rummel Fibre Co. Newark, N.J.
Marco & Oak Industries a Div, of Oak

Electro/netics Corp. Anaheim, Calif.

Philo Corp. Lansdale Div. Lansdale, Pa.
Stockwell Rubber Co, Inc.
Philadelphia, Pa.
Tower-Olschan Corp. Bridgeport, Conn.
Cutler-Hammer Inc. Power Distribution

and Control Div. Lincoln Plant

Lincoln, Ill.
Litton Precision Products Inc, USECO

Div. Litton Industries Van Nuys, Calif.

Gulton Industries Inc, Metuchen, N.J.
United-Car Inc. Chicago, Ill.
Miller Dial and Nameplate Co.
El Monte, Calif.
Radio Materials Co. Chicago, Ill.
Augat, Inc. Attleboro, Mass.
Dale Electronics, Inc. Columbus, Neb.
Elco Corp. Willow Grove, Pa.
Honeywell Inc. Div. Micro Switch
Freeport, Ill.
Whitso, Inc. Schiller Pk., Ill.
Sylvania Electric Prod. Inc. Semi-

conductor Prod. Div, Woburn, Mass.

Essex Wire Corp. Stemco

Controls Div. Mansfield, Ohio

Ravtheon Co. Components Div.

Ind. Components Oper. Quincy, Mass.

Wagner Electric Corp.

Tung-Sol Div. Livingston, N.J.

Southco Inc. Lester, Pa.
Leecraft Mfg. Co. Inc. L.I.C., N.Y.
Methode Mfg. Co. Rolling Meadows, Ill
Rendix Corp. Microwave

Devices Div. Franklin, Ind.

Weckesser Co. Inc. Chicago, Ill.
Amphenol Corp. Amphenol

Controls Div. Janesville, Wis.

Industrial Retaining Ring Co.
Irvington, N.J.
IMC Magnetics Corp, Eastern Div.
Westbury, N.Y.
Sealectro Corp. Mamaroneck, N.Y.
ETC Inc. Cleveland, Ohio
International Electronic Research Corp.
Burbank, Calif.
Rembrandt, Inc. Boston, Mass.

Table 6-3. Code List of Manufacturers (Continued)

6-4

Reference Mfr. Part # Mfr.
Designator Description Quantity or Type Mfr. Code Stock No. RS
C1 fxd. elect 1µf 35vdc 1 150D105X9035A2 Sprague 56289 0180-0291 1
C2 fxd. film 0.1µf 200vdc 1 192P10492 Sprague 56289 0160-0168 1
C3, 13, 21 fxd. film .033µf 200vdc 3 192P33392 Sprague 56289 0160-0163 1
C5 fxd. film 1µf 200vdc 1 260P10592S3 Sprague 56289 0160-2579 1
C5 fxd. film .22µf 80vdc 1 192P2248R8 Sprague 56289 0160-2453 1
C6, 8 fxd. film .001µf 200vdc 2 192P10292 Sprague 56289 0160-0153 1
C7 fxd. film .068µf 200vdc 1 192P68392 Sprague 56289 0160-0166 1
C9 fxd. film .0047µf 200vdc 1 192P47292 Sprague 56289 0160-0157 1
C10, 14 fxd. elect 20µf 50vdc 2 30D206G050DC4 Sprague 56289 0160-0049 1
C11, 12, 22 NOT ASSIGNED - - - - - ­C15, 18A, 25 fxd. ceramic .02µf 600vdc
D1S6 3 ED – 02 Erie 72982 0150-0024 1
C16 fxd. elect 325µf 35vdc 1 D34656 HLAB 09182 0180-0332 1
C17, 23 fxd. elect 1450µf 45vdc 2 D39532 HLAB 09182 0180-1893 1
C19 fxd. elect 1500µf 40vdc 1 D38733 HLAB 09182 0180-1894 1
C20 fxd. film .0022µf 200vdc 1 192P22292 Sprague 56289 0160-0154 1
C24 fxd. film 1µf 200vdc 1 118P10592S3 Sprague 56289 0160-2465 1

CR1, 2, 4

8, 9, 16 Diode SI 200prv 250MW 6 HLAB 09182 1901-0033 6

CR3, 5-7

11, 12, 14
15, 17, 18

21, 22 NOT ASSIGNED - - - -
CR10, 13, 20 Diode si. 2.4V @ 100ma 3 HLAB 09182 1901-0460 3
CR19, 23 Rect. si. 200ma 10prv 2 HLAB 09182 1901-0461 2
CR24-28, 32 Rect. si. 500ma 200prv 6 1N3253 R.C.A. 02735 1901-0369 6
CR29, 30A Rect. si. 1A 200prv 2 1N5059 G.E. 03508 1901-0322 2
CR31 SCR 1.6A 50prv 1 C6F G.E. 03508 1884-0033 1
CR33, 34 NOT USED - - - - - -

DS1 Lamp neon part of S1 ass'y Ref HLAB 09182 2140-0244 1
F1 Fuse cartridge 1A @250V 3AG 1 312001 Littlefuse 75915 2110-0001 5
L1, 2 Coil 2 HLAB 09182 9100-1854 1
Q1 Dill. amp NPN 1 HLAB 09182 1854-0221 1

Q2, 3 SS NPN si. 2 HLAB 09182 1854-0027 2
Q4, 6 NOT ASSIGNED - - - - - ­Q5 SS NPN si. 1 4JX16A1014 G.E. 03508 1854-0071 1
Q7, 8 SS PNP si. 1 2N2907A Sprague 56289 1853-0099 2
Q9, 10,

13-15 SS NPN si. 5 HLAB 09182 1854-0027 5
Q11 Power NPN si. 1 HLAB 09182 1854-0225 1
Q12 SS PNP si. 1 40362 R.C.A. 02735 1853-0041 1
Q16 Unijunction si. 1 2N2646 G.E. 03508 1855-0010 1

R1, 2 fxd. ww 1KΩ ±5% 3w 2 242E1025 Sprague 56289 0813-0001 1
R3 fxd. met. film 221KΩ±1% ⅛w 1 Type CEA T-O I.R.C. 07716 0757-0473 1
R4 fxd. met. film 27.1KΩ±1% ⅛w 1 Type CEA T-O I.R.C. 07716 0757-0452 1
R5, 6 fxd. met. film 432KΩ±1% ⅛w 2 Type CEA T-O I.R.C. 07716 0757-0480 2
R7, 8 fxd. met. film 43KΩ±1% ⅛w 2 Type CEA T-O I.R.C. 07716 0698-5090 2
R9 fxd. comp 120Ω ±5% ½w 1 EB-1215 A.B. 01121 0686-1215 1
R10 fxd. met. film 390KΩ±1% ⅛w 1 Type CEA T-O I.R.C. 07716 0698-5093 1
R11 var. ww 22KΩ ±10% 1 HLAB 09182 2100-1850 1
R12 fxd. met. film 17.8KΩ±1% ¼w 1 Type CEA T-O I.R.C. 07716 0698-4722 1

6-5

Reference Mfr. Part # Mfr.
Designator Description Quantity or Type Mfr. Code Stock No. RS
R13, 15 fxd, met. film 1MEG±1% ⅛w 2 Type CEA T-O I.R.C. 07716 0757-0344 1

R14, 16 var. ww 15KΩ, ±5% 1W @50°C 2 Model 100 I.R.C. 07716 2100-0896 1
R17 fxd, ww Factory selected,
approx. value is 297 ±1%
¼w TC20ppm 1 HLAB 09182 0811-1929 1
R18 fxd, ww 5.9K ±1% 0±5ppm/°C 1 HLAB 09182 0811-1978 1
R19 fxd, ww 5.5K ±1%
+ 15 ±5ppm/°C 1 HLAB 09182 0811-1957 1
R20 var. ww 10KΩ ±5% 2W @
25°C (10 turn) 1 HLAB 09182 2100-1866 1
R21 fxd, met. film 2KΩ ±1% ⅛w 1 Type CEA T-O I.R.C. 07716 0757-0283 1
R22 Thermister 64Ω ±10% 1 LB 16 J1 Fenwal 15801 0837-0023 1
R23 fxd, ww 1Ω ±5% 8W 1 Type T-7A R.C.L. 01686 0811-2133 1
R24 fxd, comp 7.5KΩ ±5% ½w 1 EB-7525 A.B. 01121 0686-7525 1
R25 var. ww 1KΩ ±5% 1 HLAB 09182 2100-1847 1
R26, 32, 43 fxd, comp 10KΩ ±5% ½w 3 EB-1035 A.B. 01121 0686-1035 1
R27, 28, 33,

60 fxd, comp 1KΩ ±5% ½w 4 EB-1025 A.B. 01121 0686-1025 1
R29 fxd, comp 100Ω ±5% ½w 1 EB -1015 A.B. 01121 0686-1015 1
R30 fxd, comp 5.1KΩ ±5% ½w 1 EB-5125 A.B. 01121 0686-5125 1
R31 fxd, comp 3.9KΩ ±5% ½w 1 EB-3925 A,B. 01121 0686-3925 1.
R34 fxd, comp 390Ω ±5% ½w 1 EB-3915 A.B. 01121 0686-3915 1
R35, 59 fxd, comp 680Ω ±5% ½w 2 EB-6815 A.B. 01121 0686-6815 1
R36, 61 fxd, comp 2KΩ ±5% ½w 2 EB-2025 A.B. 01121 0686-2025 1
R37 fxd, comp 10Ω ±5% ½w 1 EB-1005 A.B. 01121 0686-1005 1
R38, 45 fxd, comp 1.5KΩ ±5% ½w 2 EB-1525 A. B. 01121 0686-1525 1
R39 fxd, met, ox, 300Ω ±5% 2W 1 Type C425 Corning 16299 0698-3630 1
R40 fxd, ww 100Ω ±5% 5W 1 243E4015 Sprague 56289 0811-1857 1
R41 fxd, comp 200Ω ±5% ½w 1 EB-2015 A.B. 01121 0686-2015 1
R42 fxd, met. film 42.2Ω ±1% ⅛w 1 Type CEA T-O I.R.C. 07716 0757-0316 1
R44 fxd, comp 4.3KΩ ±5% ½w 1 EB-4325 A.B. 01121 0686-4325 1
R46, 53 fxd, comp 2.7KΩ ±5% ½w 2 EB-2725 A.B. 01121 0686-2725 1
R47, 48 fxd, met. film 1.5KΩ ±1% ⅛w 2 Type CEA T-O I.R.C. 07716 0757-0427 1
R49 fxd, ww 714Ω ±1% ¼w 1 HLAB 09182 0811-1935 1
R50 fxd, ww .24Ω ±5% 1 Type BWH I. R. C. 07716 0811-1758 1
R51, 58 NOT ASSIGNED - - - - - ­R52 fxd, comp 2.4KΩ ±5% ½w 1 EB-2428 A.B. 01121 0686-2425 1
R54 fxd, ww 600Ω ±5% 5w 1 243E601,5 Sprague 56289 0811-1860 1
R55 fxd, comp 33KΩ ±5% ½w 1 EB-3335 A.B. 01121 0686-3336 1
R56, 66 fxd, comp SELECTIVE 2 Type -EB A.B. 01121
R57 Thermister 100K ±10% 1 51 TG 4 Gulton 90634 0837-0026 1
R62 fxd, comp 220Ω ±5% ½w 1 EB-2215 A.B. 01121 0686-2215 1
R63 fxd, ww .51Ω ±5% 1 Type BWH I.R.C. 07716 0811-0929 1
R64 fxd, met. film 1.21KΩ ±1% ⅛w 1 Type CEA T-O I.R.C. 07716 0757-0274 1
R65 var. ww 10Ω 1 Type 110-F4 C.T.S. 11236 2100-1822 1
R67 var. ww 1KΩ 1 Type 110-F4 C.T. S. 11236 2100-0391 1
R68 fxd, comp 560 ±5% ½w 1 EB-5615 A.B. 01121 0686-5615 1
R69 fxd, met, film 19.1KΩ ±1% ⅛w 1 Type CEA T-O I.R.C. 07716 0698-4484 1

S1 Switch, pilot lt. (red) ON/OFF 1 54-61681-26 AlH Oak 87034 3101-0100 1
S2 Switch, wafer 1 HLAB 09182 3100-1911 1

T1 Power Transformer 1 HLAB 09182 9100-2127 1
VR1 Zener 6.2V ±5% 250 mW 1 1N825 Transitron 03877 1902-0777 1
VR2 Diode-Zener 9.4V±5% 500mV 1 1N2163 U. S. Semcor 06751 1902-0762 1

6-6

Reference Mfr. Part # Mfr.
Designator Description Quantity or Type Mfr. Code Stock No. RS
5 Way binding post (red) 1 DF21 (maroon) HLAB 09182 1510-0040 1

5 Way binding post (black) 2 DF21 (bl) Superior 58474 1510-0039 1
Cable clamp ¼ I. D. 1 T4-4 Whitehead 79307 1400-0330 1
Line cord plug PH151 7½ ft. 1 KH-4096 Beldon 70903 8120-0050 1
Strain relief bushing 1 SR-5P-1 Heyco 28520 0400-0013 1
Knob ¼ insert pointer 2 HLAB 09182 0370-0084 1
Knob ⅝ dia 2 HLAB 09182 0370-0137 1
Jumper 7 422-13-11 013 Linch 71785 0360-1143 2
Barrier strip 1 HLAB 09182 0360-1234 1
Rubber bumper 4 MB50 Stockwell 87575 0403-0086 1
Bezel 1/6 MOD 1 HLAB 09182 4040-0295 1
Fuse holder 1 342014 Littlefuse 75915 1400-0084 1
Meter 2¼" DUAL 0-24V 0-1.2A 1 HLAB 09182 1120-1226 1
Heat dissipater 1 NF-207 Walefield 05820 1205-0033 1
Spring 4 HLAB 09182 1460-0720 1
Fastener 8 C8091 632-248 Tinnerman 89032 0510-0275 2
Mica insulator 1 734 Reliance 08530 0340-0174 1
Insulator, Transistor pin 2 HLAB 09182 0340-0166 1
Insulator 2 HLAB 09182 0340-0168 1
Can-outer 1 HLAB 09182 5000-6070
Can-inner 1 HLAB 09182 5000-6071
Side chassis - right 1 HLAB 09182 5000-6057
Side chassis - left 1 HLAB 09182 5000-6058
Bracket - heat sink 2 HLAB 09182 5000-6060
Blank panel - front 1 HLAB 09182 5000-6062
Panel front 1 HLAB 09182 5000-6069
Cover 2 HLAB 09182 5000-6061
Guard-angle 1 HLAB 09182 5020-5540
Rubber bumper 3 4072 HLAB 09182 0403-0086 1

OPTION 06:
Overvoltage "Crowbar"
Protector Model 6916A 1 HLAB 09182 Model 6916A

6-7

APPENDIX A

Model

61.01A

6102A

6106A

6111A

6112A

6113A

6116A

Trip Voltage Range

3.2-23V

3.2-44V

20-110V

3.2-23V

3.2-44V

3.2-13V

20-110V

Option 11, Overvoltage Protection "Crowbar"

DESCRIPTION:

This option is installed in DC Power Supplies, 6101A, 6102A, 6106A, 6111A, 6112A, 6113A, and 6116A,
and tested at the factory. It consists of a printed circuit board, screwdriver type front panel potentiometer,
and four wires that are soldered to the main power supply board.

The crowbar monitors the output voltage of the power supply and fires an SCR that shorts the output when it
exceeds the preset trip voltage. The trip voltage is determined by the setting of the CROWBAR ADJUST
control on the front panel. The trip voltage range is as follows:

To prevent transients from falsely tripping the crowbar, the trip voltage must be set higher than the power supply
output voltage by the following margin: 7% of the output voltage +1V. The margin represents the minimum crowbar
trip setting for a given output voltage; the trip voltage can always be set higher than this margin.

OPERATION:

1. Turn the CROWBAR ADJUST fully clockwise to set the trip voltage to maximum.

2. Set the power supply VOLTAGE control for the desired crowbar trip voltage. To prevent false crowbar
tripping, the trip voltage should exceed the desired output voltage by 7% of the output voltage +1V.

3. Slowly turn the CROWBAR ADJUST counterclockwise until the crowbar trips, and the output fails to a
small positive voltage (about 1.8V or less).

4. The crowbar will remain activated and the output shorted until the supply is turned off. To reset the
crowbar, turn the supply off, then on.

A-1

Table A-1. Replaceable Parts

REF.

DESIG.

TQ

MRF. PART NO.

MFR

CODE

HP

PART NO.

RS

C1
C2

CR1-3
CR4

Ql,2
R1

R2
R3
R4
R5
R6
R7
R8

T1
VR1

VR2

fxd, elect lµF 50Vdc
fxd, mica 510µF 500Vdc

Diode, Si. 200mA 200prv
SCR 7.4A 100prv

SS NPN Si.
fxd, met. film 10Ω ±1%⅛W

fxd, comp 1.31KΩ ±5% 1W
fxd, met. film 1.21KΩ ±1% ⅛W
fxd, met. film 7.5KΩ ±1% ⅛W
var. ww 10KΩ ±5% (CROWBAR ADJ.)
fxd, ww 1KΩ ±5% 3W
fxd, comp 22Ω ±5% ½W
fxd, met, film 510Ω ±1% ¼W

Transformer, Pulse
Diode, zener 6.19V±5%

Diode, zener 2.37V±5%

1
1

3
1

2
1

1
1
1
1
1
1
1

1
1

1

30D105G050BA2
RCM15E511J

C20A
2N3417
Type CEA T-O

GB-1325
Type CEA T-O
Type CEA T-O

242E1025
EB-2205
Type CEB T-O

56289
04062

02182
03508

03508
07716

01121
07716
07716
09182
56289
01121
07716

09182
09182

09182

0180-0108
0140-0047

1901-0033
1884-0031

1854-0087
0757-0346

0689-1325
0757-0274
0757-0440
2100-1854
0913-0001
0686-2205
0698-5145

5080-7122
1902-0049

1902-3002

1
1

3
1
2
1
1
1
1
1
1
1
1
1
1
1

MISCELLANEOUS

Heat Sink, CR4
Insulator, CR4
Mica Washer, CR4
Cable Clamp
Bushing, Potentiometer (R5)
Nut, Hex (R5)
Label, Information,

(CROWBAR ADJUST)

Modified Front Panel,

Includes Components

Printed Circuit Board Assembly,

Includes Components

1
1
1
1
1
1

1
1
1

T4-4

09182
09182
09182
79307
09182
09182

09182
09182
09182

5000-6229
0340-0462
2190-0709
1400-0330
1410-0052
2950-0034

7124-0369
06101-60003
06101-60021

A-2

R7

22Ω

±5%

1/2W

Q1

R1

10Ω

±1%

1/8W

C2

510µF

50V

CR2

CR1
R6
1K
3W

Q2

R8

510

±1%

1/4W

CR3

R3

1.21K
±1%

1/8W

R5

10K

R4

7.5K
±1%

1/8W

C1
1µF
50V

VR2

2.4V

VR1

6.2V

R2

1.3K
±5%

2W

CR4

CROWBAR

ADJUST

+OUT

-OUT

DC POWER SUPPLY

CIRCUIT PATENTS APPLIED FOR LICENSE TO USE
MUST BE OBTAINED IN WRITING FROM HEWLETT­PACKARD CO. HARRISON DIVISION

FROM INBOARD
SIDE OF R50

BIAS VOLTAGE FROM

COLLECTOR OF Q11

1 5

2 6

4

3

Figure A-1. Model 6101A and 6111A Overvoltage Protection Crowbar

A-3

Q12

Q13

R45
10K

R47

1.5k
⅛W

R44

4.3K
R48

1.5K
⅛W

Q14

R45

1.5K

Q15

R52

2.4K

R53

2.7K

C13
.033µF
200V

C16

325µF

35V

C25

.02µF

R49

714

¼W

C14
20µF
50V

CR19

VR1

VR2

R46

2.7K

CR20

R14
15K

R10

390K

⅛W

R11
22K

R16
15K

R13

1MEG

¼W

R12

17.8K
¼W

R26
10K

R15 1MEG ¼W

R24

7.5K

R28

1K

R25

1K

CURRENT

LIMIT

R29
100

C5

.22µF

80V

CR4

CR8

Q5

R27

1K

R65
10Ω

R50

R64

1.21K ⅛W

R22

THERMISTOR

R42

42.2 ⅛W

R67

1K

R21

2K ⅛W

R66

select

+

R69

19.1K
⅛W

R23

1Ω 8W

Q7

Q8

Q2

Q3

R7
43K
⅛W

R8
43K
⅛W

R5

432K

⅛W

R6
432K
⅛W

R30

5.1K

R3
221K
⅛W

R2
1K
3W

R4

27.4K
⅛W

R9

120

R1

1K, 3W

C3
.033µF
200V

C2
.1µF
200V

C6

.001µF

200V

R32
10k

R31

3.9K

CR1

CR2

Q1AQ1B

CR32

R63

.51

C24
1µF

200V

C23

1450µF

45V

C4

1µF

200V

R20
10K

C1
1µF
35V

C7
.068µF
200V

R33

1K

R41
200

R34
390

C8

.001µF

200V

R35
680

CR13

R36

2K

R39
300
2W

CR9

CR10

C6

.001µF

200V

Q9

Q10

R37

10

CR16

R38

1.5K

Q11

L2

R51

R61

2K

R56

select

+

R59

680

CR28

C10

20µF

50V

C20

.0022µF

200V

CR23

CR24

CR25

L1

CR31

R60

1K

R62
220

C17

1450µF

45V

CR26

CR27

CR29

CR30A

C18A

.02µF 600V

C15

.02µF 600V

R54

600Ω

5W

R40

100Ω

5W

C19

1500µF

40V

R17+ ¼W

297*

M

R68
560

C21

.033µF

200V

2

38

36

37

11

25V

-2.5V

15

51

24

27

41

53

42

33VAC

45

46

47

48

49

44

50

R55
33K

50V

42

VAC

32

33

28

35

43

29

30

16

34

21

17

23

20

22

18

40

19

VOLTAGE

INPUT

CIRCUIT

CURRENT

LIMIT

CIRCUIT

OVEN

CONTROL

CIRCUIT

20V

2.5V

REFERENCE
REGULATOR

CIRCUIT

METER

CIRCUIT

54

31

26

52

25

SERIES

REGULATOR

DRIVER AND

ERROR AMPLIFIER

35VAC

14

13

12

+12.4V

+S

-9.4

CIRCUIT PATENTS APPLIED FOR
LICENSE TO USE MUST BE OBTAINED
IN WRITING FROM HEWLETT PACKARD
HARRISON DIVISION

S2 POSITIONS
1 – 2.4V
2 – 24v
3 – 1.2A
4 – .12A

A3

A2

A1

A10

A9

A7

+OUT

+S

A4

A5

A6

A8

-S

-OUT

BIAS

HEATER

VOLTAGE
COARSE

CURRENT SAMPLING RESISTOR

+F

S1

F1
1A

-F

64Ω ±10%

.24Ω

R18

5.9K±1%

0±5ppm/°C

R19

5.5K±1%

+15±5ppm/°C

1

Q16

39

NOTES:

1. ALL RESISTORS ARE ½W, 5% UNLESS OTHERWISE NOTED.

2. ALL ⅛W AND ¼W RESISTORS ARE 1% INTOLERANCE.

3. + DENOTES NOMINAL VALUE, COMPONENTS SELECTED FOR OPTIMAL PERFORMANCE.

4. * DENOTES 20PPM WIRE TEMPERATURE COEFFICIENT.

5. REAR TERMINALS ARE SHOWN IN NORMAL STRAPPING.

6. DENOTES VOLTAGE FEEDBACK SIGNAL.

7. DENOTES CURRENT FEEDBACK SIGNAL.

8. TRANSFORMER SHOWN STRAPPED FOR 115VAC OPERATION. SEE
INSTRUCTION MANUAL FOR 220VAC.

9. DC VOLTAGES WERE MEASURED UNDER THE FOLLOWING CONDITIONS:
A. SIMPSON MODEL 260 OR EQUIVALENT.
B. 115VAC INPUT.
C. VOLTAGES REFERRED TO +S UNLESS OTHERWISE NOTED.
D. VOLTAGES ARE TYPICAL, ±10% UNLESS OTHERWISE NOTED.
E. SUPPLY IN CONSTANT VOLTAGE OPERATION AT MAXIMUM RATED OUTPUT WITH NO LOAD
CONNECTED. CURRENT CONTROLS SHOULD BE TURNED FULLY CLOCKWISE

Model 6101A, Schematic Diagram

2 3

41

2 3

41

2 3

41

VOLTAGE

FINE

6

7

8

11

10

9

12

13

14

15

4

3

2

1

+6.2

T1

9100-2127

A1'

A11 A3

A5

A8

ACC

AC

MANUAL CHANGES

SERIAL

MAKE

CHANGES

Prefix

Number

All
6L
6L
1A
1E
1137A
1137A
1137A
1629A

–
0101-0600
0601-0646
0646-0665
0666-0745
0746-0805
0806-0910
0911-1275
1276-up

Errata
1
1,2
1,2,3
1,2,3,4
1 trhu 5
1 trhu 6
1 trhu 8
1 trhu 9

CR30B

CR29

CR33

CR34

C19
1500
40V

T1

35VAC

12

13

15

C18B
.02
600V

38

37

R24

R25

R58

To R28

To 9.4V REF.

Model 6101A DC Power Supply

Manual HP Part Number 06101-00001

Make all corrections in the manual according to errata below, then check the following table for your power supply

serial number and enter any listed change(s) in the manual.

In the replaceable parts table, and on the schematic
diagram, make the following changes:

CR13: Change from one triple function diode to three

series diodes, CR5, CR6, and CR7, 1N5059, HP Part
No. 1901-0327.

CHANGE 2:

ERRATA:
In the replaceable parts table, change Q7, 8 to
2N2907A. Sprague, 56289, 1853-0099.

CHANGE 1:

In the replaceable parts table, make the following changes:

C15: Delete C15.
C18A: Delete C18A.
CR30A: Delete CR30A.
CR29, CR30B, CR33, CR34: Add new rectifier diodes,
1A, 200prv, 1N5059, G.E., HP Part No. 1901-0327.
Q2, Q3: Change to HP Part No. 1864-0071, SS NPN Si.
R20: Change from 10kΩ to 20kΩ ±5%, 2W (10 turn) HP

Part No. 2100-1867.
On the schematic at the rear of the manual, and on Figure
4-2, change the main supply rectifier to bridge type as
shown below.

In the replaceable parts table, make the following change:

CHANGE 3:

R51: Add new resistor, 20Ω ±5%, ½W, HP Part No.

0686-2005.

On the schematic at the rear of the manual, add R51 in

series with capacitor C4, on the -S side of C4.
On the title page, change the serial number prefix from 6L
to 1A.

CHANGE 4:

In the replaceable parts table, make the following changes:

S1: Change to new type pushbutton switch, HP Part

No.3101-1248.

T1: Change Power transformer to HP Part No. 5080-7181.

CHANGE 5:
The serial prefix of this unit has been changed to 1137A.
This is the only change.

CHANGE 6:
The standard colors for this instrument are now mint gray
(for front and rear panels) and olive gray (for all top,
bottom, side, and other external surfaces). Option X95
designates use of the former color scheme of light gray and
blue gray. Option A85 designates use of a light gray front
panel with olive gray used for all other external surfaces.
New part numbers are shown on back.

CHANGE 7:
In the replaceable parts table and on the schematic, make
the following changes:

R13: Change to 562kΩ, ⅛W, HP Part No. 0757-0483.
R24: Change to 5.1kΩ, ±5%, ½W, HP Part No. 0686-

5125.

R58: Add R58, var. ww, 5kΩ, ±5%, HP Part No. 2100-

0741.

R58 is added as follows:

The above changes have been made to allow for Option
040 (multiprogrammer remote programming) operation; to
allow the current limit to be set to 110 ±2% of rated
current.

Manual Changes/Model 6101A

DESCRIPTION

HP PART NO

STANDARD

OPTION A85

OPTION X95

Panel Front, Lettered
Side Chassis, Left
Side Chassis, Right
Cover
Heat Sink

06101-00004

5060-7955
5060-7956
5000-9424
5060-7966

06101-60001
5060-6119
5060-6118
5000-6061
5060-6124

CR31

R62

1k

CR23 L2

Q16

2

1

Manual HP Part No. 06101-90001
Page — 2 —

ERRATA:
In Table 1-1 and paragraph 5-23, change the OUTPUT
IMPEDANCE specification to read:

OUTPUT IMPEDANCE (Typical): Approximated by a

0.5 milliohm resistance in series with a 1 microhenry
Inductance.

 Add to the parts list the replacement lamp for illuminated

switch 3101-1248, which is used in those supplies that
include Change 4. The HP Part No. of the type A1H lamp
is 2140-0244.

CHANGE 8:
In Appendix A, Option 11 replacement parts table A1,
change CR4 from HP Part No. 1884-0031 to 1884-0032.

CHANGE 9:
This change reduces the magnetic radiation induced in the
oven control circuit to ensure a ripple specification of
100µV peak-to-peak.

In the replaceable parts table and on the schematic, make
the following changes:

R60: Delete.
R62: Change to 1k, 5%, ½W, HP Part No. 0686-1025.
CR23: change to HP Part No 1901-0033 and connect in

shunt with L2 as shown below.
On the schematic, change the oven control circuit as shown
below:

ERRATA:
The Lime-gray meter bezel has been replaced by a black
one, HP Part No. 4040-0414.

 Change the part number of R58 (added to the current

limit circuit by Change 7) to 2100-1775. The resistor has
not been changed; just its part number has.

11-29-76

The front panel binding posts have been changed to a type
with better designed insulation. Delete the two types of
posts listed on page 6-7 of the parts list end add: black
binding post, HP Part No. 1510-0114 (qty. 2); and red
binding post, HP Part No.1810-0115 (qty. 1).

ERRATA: