led. Ver. v. Historie v/d Radio
Met dank aan Hein Ros
66 403 45.1-10
20/564/01
1 | Block diagram | 6 |
---|---|---|
2 | Rear view | 10 |
3 | Front view with controls | 13 |
4 | Various ways of connection | 14 |
5 | Attenuator circuit | 17 |
6 | Quadratic network | 17 |
7 | Current-voltage characteristic | 18 |
8 | Parabolic curve | Eð |
9 | Removing the knob | 22 |
10 | Bottom view of interior | 25 |
11 | Right-hand side view | 27 |
12 | Left-hand side view | 29 |
13 | Pulse shape | 30 |
14 | Mains-transformer | 35 |
15 | Bottom view of exterior | 41 |
16 | Top view | 41 |
17 | Rear view without rear plate | 42 |
18 | Switch segments | 43 |
19 | Unit U1. (left), switch plate | 44 |
20 | Unit U1, (right), switch plate | 44 |
21 | Unit U2, calibration voltage generator |
|
22 | Unit U3. pre-amplifier | 45 |
23 | Unit U4, supply unit | 40 |
24 | Unit U5, output stage | 47 |
25 | Unit U6. quadratic network | 48 |
26 | Measuring cable | 49 |
27 | Circuit diagram | 53 |
GENI | ERAL PART | 5 |
---|---|---|
I. | Introduction | 5 |
H. | Description of the block diagram | 6 |
III. | Technical data | 8 |
IV. | Accessories | 9 |
DIRE | CTIONS FOR USE | 10 |
V. | Installation | 10 |
VI. | Operation | 12 |
SERV | ICE DATA | 15 |
VII. | Description of the mode of operation | 15 |
VIII. | How to gain access to the parts | 22 |
IX. | Maintenance | 23 |
Х. | Adjusting devices and their functions | 23 |
XI. | Checks and adjustments | 24 |
XII. | Replacing parts | 32 |
XIII. | A few data for fault analysis | 35 |
XIV. | List of parts | 36 |
By means of the amplifier voltmeter PM 2520 a.c. voltages of 100 µV...300 V can be measured in a frequency range from 10 c/s to 1 Mc/s.
The apparatus has the following special properties:
The apparatus is equipped with an accurately indicating meter having three scale divisions, viz.:
For the purpose of checking the input voltage, an oscilloscope can be connected to two sockets at the front of the apparatus. These sockets can also be used as amplifier output.
The apparatus moreover has a socket for connection of a recorder, so that it is possible to record the voltage under test by means of an automatic compensator PR 2210A or PR 2400A.
In principle the apparatus consists of two amplifiers with a high input impedance and which are perfectly symmetrical with respect to earth.
The voltage under test is amplified by means of two amplifier stages (B1', 11', 2' and 12') preceded by an impedance-converting preliminary stage (B1, 11) and followed by an output amplifier (B3', 13', 4', 14'). According to the measuring range selected the voltage under test is attenuated at the input or between the amplifier stages by the measuring-range switch. The three amplifier stages of this switch are coupled mechanically and are carried by the same shaft.
Via the Graetz rectilier the voltage is supplied to a quadratic network and indicated by the moving-coil instrument.
A calibrating-voltage generator is provided for calibrating the measuring instrument. This generator delivers constant sinusoidal voltages of 10 mV and 3 V with a frequency of 1000 c/s.
Fig. 1. Block diagram
The supply voltages for the amplifier and the calibrating voltage generator are electronically stabilized by the valves B5...B7. The amplified input voltage is available at the sockets "OUTPUT". The sockets "RECORDER" at the rear of the instrument can be used for connecting a recorder. During the connection of a recorder the moving-coil instrument is cut out.
Properties given as figures with tolerances are guaranteed by us. Numerical values without tolerances serve as a guide for the user and apply to the properties of an average instrument.
Unless stated otherwise, the numerical values refer to nominal mains voltage.
Measuring range | 100 µV300 V subdivided in 12 ranges |
---|---|
with max. values: 1, 3, 10, 30, 100, 300 mV | |
and 1. 3. 10. 30. 100 and 300 V. | |
dB-range | -20 dB to +20 dB |
0 dB - 0.775 V across 600 Ω = 1 mW. |
Input impedance | Input resis | stance | Input capa | Input capacitance | ||
---|---|---|---|---|---|---|
in measuring range | symm. | asymm. | sy m m. | asymm. | ||
1 mV 1 V
3 V300 V |
8 Μ
Ω
20 Μ Ω |
4 ΜΩ
10 ΜΩ |
15 pF
7,5 pF |
30 pF
15 pF |
After calibration for a sinewave voltage of 10 mV
(f.s.d.) and 1 Kc/s | ± 1% |
---|---|
Attenuation | ± 1% |
Meter | ± 1.5 % |
Frequency response | |
20 c/s - 200 Kc/s | +- 1 % |
10 c/s - 1 Mc/s | 30 |
for non sinusoidal voltages following accumulative errors should be taken into account
for crest factor 1: | +- 34% |
---|---|
for crest factor 15: | 3% |
Pre-deflection |
< 50 µV (in the 1 mV-range, input termi-
nals terminated with 100 kΩ and screened). |
Calibrating voltages |
10 mV and 3 V.
Frequency 100 c/s. |
Proportion between peak and | ŭ |
r.m.svalue | U rdmas = max. 5. |
Common mode rejection I.e. the attenuation of signals which are in phase with respect to earth and applied between the input terminals and 60 dB for 1 V. 50 c/s. earth Output for recorder Measuring range on sockets "RECORDER" 0 - 100 mV Internal resistance Potential of sockets "RECORDER" with respect approx. 100 V to earth Max. amplification on sockets "OUTPUT" 40 imesInternal resistance Supply By means of a voltage selector the apparatus can be adjusted to mains voltages of 110. 125, 145, 200, 220 and 245 V. frequency 40...100 c/s (frequencies < 50 c/s only at nominal mains voltage). Measuring error at mains-volt--- 1 % age variations of + or -10% Drift of calibrating voltage at mains-voltage variations of 1 or -10% - 0.5 % Power consumption approx. 70 W Dimensions and weight height 24 cm, depth 22 cm, width 36 cm weight 9.7 kg.
Mains cable Manual Measuring cable
By means of a voltage selector the apparatus can be adjusted to mains voltages of 110, 125, 145, 200, 220 and 245 V. The voltage value adjusted can be read through the round opening in the rear wall.
Adjustment to other mains voltages is effected as follows:
Fig. 2. Rear view
Earth the instrument according to the local safety regulations. This can be done via:
Avoid double earthing; it may increase the risk of hum.
Proceed as follows:
The pre-deflection is adjusted as follows:
For calibrating purposes the front plate of the apparatus has two sockets at which stabilized calibrating voltages of 10 mV and 3 V (1000 c/s) are available.
The 10-mV voltage serves to check and calibrate the amplifier. while the 3-V voltage can be used for checking the pre-attenuator.
Calibration is effected as follows:
Set the measuring-range switch to 10 mV.
Connect socket "10 mV" to one of the sockets "1 mV-300 V": the free socket must be connected to the earth socket.
Check whether the instrument indicates exactly 100 on the scale 0-100. If necessary, readjust potentiometer R37 (screw-driver adjustment, right-hand panel).
- Check whether the instrument indicates a value between 296 and 304 V on the 0-300 scale. If the meter indicates a different value, the adjustment of chapter XI E must be carried out.
The instrument has a provision for symmetry adjustment, by means of which the effects of a.c. fields near the measuring arrangement can be suppressed to a maximum degree.
This adjustment is carried out in the following way by means of potentiometer "BALANCE" on the front plate:
Fig. 3. Front view with controls
The voltage under test is connected to the upper terminals "1 mV - 300 V" (Fig. 4a).
The voltage under test is connected to one of the upper terminals "I mV – 300 V" and the terminal "*". The free terminal is connected to socket "*" (Fig. 4b).
The amplifier output "OUTPUT" can be used as input both for the symmetrical and the asymmetrical methods.
A recorder must be connected free from earth, as both sockets carry a voltage of about 100 V with respect to earth.
At the rear of the instrument there are two sockets for connection of a recorder (Fig. 2).
If a plug is inserted into one of the sockets, the instrument is switched off automatically.
The output voltage is 0-100 mV (100 mV corresponds to full-scale deflection on the meter).
When connecting a recorder, the internal resistance of the measuring instrument must be taken into account.
Fig. 4. Various ways of connection
The a.c. voltage under test is applied to the input attenuator via sockets "1 mV – 300 V".
In the measuring ranges 1 mV · 1 V the input signal is not attenuated. In the case of a symmetrical input the input resistance is 8 MQ.
In the higher voltage ranges 3 V - 300 V the input signal is attenuated by the voltage divider R1-R3 (R101-R103), as a result of which the input resistance in these ranges is 20 MQ with symmetrical input.
Via capacitor C32 (C132) and resistor R4 (R104) the signal is applied to the control grid of valve B1 (B11). These valves act as cathode followers and convert the high input impedance to a low impedance. Resistor R5 (R105) causes a negative feedback which increases the input impedance. Symmetry is obtained by means of potentiometer R93.
The signal now having a lower impedance is applied to the second attenuator R8-R12 (R108-R112) (Fig. 5).
Via capacitor C4 (C104) and resistor R16 (R116) the signal now reaches the control grid of valve B1' (B11') of the pre-amplifier and is subsequently amplified by two stages: in this case as well the output is a cathode-follower stage.
The RC network consisting of R94-C40 and R25 (R194-C140 and R125) constitutes a negative feedback to the cathode potential of valve B1' (B11'), on account of which the frequency-response curve is corrected.
On the low side of this curve the filter represents a higher impedance than on the high side.
The common mode rejection is adjusted by means of resistors R99 and R58. The grid bias is symmetrically adjusted by means of R99, while the decoupling is adjusted by R58.
The third attenuator determines which voltage range. 3 mV or 10 mV, will be used by switching over the resistors R26 and R27 (R126 and R127).
The amplified signal is applied to the control grid of value B3' (B13') of the output amplifier via capacitors C9 (C109) and resistors R35 (R135).
The two following stages then amplify the signal which is then given a low impedance by cathode-follower B4' (B14') and applied to the Graetz rectifier GR1...GR4.
Electrical zero adjustment is effected by adjusting the control-grid voltages of the valves B3' and B13' symmetrically by means of potentiometer R31 ("0" on the text plate).
The sensitivity of the indication and of the amplification is determined by the value of potentiometer R37 in the cathode lead of values B3' and B13'.
The frequency-response curve is adjusted at high frequencies by means of trimmer C11 (C111).
The r.m.s.-value rectification is effected by a network consisting of a special circuit of diodes and resistors (Fig. 6). The special properties of this network ensure that the current flowing through the indicating meter is proportional to the square of the voltage under test.
This quadratic function corresponds to a parabolic curve. In this way it is ensured that for indicating the r.m.s. value the scale of the meter can be calibrated almost linearly.
To explain the r.m.s.-value rectification the mode of operation of the diode circuit will first be described in detail.
Fig. 7 shows the current/voltage characteristics for average-value rectification (A), peak-value rectification (B) and r.m.s.-value rectification (C). The uninterrupted line always indicates the practical value and the dotted line the theoretical value.
Fig. 6. Quadratic network
Fig. 7. Current-voltage characteristic
These figures reveal that the curve is parabolic for the r.m.s.value rectification and represents a value between the average and peak values. As with a parabola the proportion differs in all points. r.m.s.-value rectification cannot be achieved with a linear circuit. For practical purposes the test circuit must be arranged so that the current flowing through the instrument corresponds as accurately as possible to the parabolic curve, so that it is proportional to the square of the voltage.
The circuit of the network including the diodes GR5...GR8 bends the linear characteristic (working line) in specific ratios, as a result of which the parabolic shape of the curve is approached (Fig. 8).
On account of this step-wise adaptation it is possible to arrive at such an approximation of the parabolic curve that the deviations lie within fixed tolerance limits.
The resistors R50-R51. R49-R52 and R58-R53 are potential dividers delivering the intermittently occurring voltage to the relevant diode, thus determining the point of deflection.
After the input voltage has been amplified and rectified by the Graetz circuit, the diode in the relevant circuit becomes conductive when the deflection voltage is obtained, so that the resistance value of this circuit decreases.
The same process occurs in one or more diode circuits, dependent
on the voltage: every time the curve will be deflected at the moment when the relevant diode becomes conductive, so that the curve will follow a parabolic path (Fig. 8).
Fig. 8. Parabolic curve
Diode GR9 is provided for limiting the blocking current; but for this diode the blocking current would be a factor 4 higher. The heating of the diodes GR5...GR8 is compensated by the diodes GR10 and GR11.
Zener diode GR17 protects the indicating meter against too high a voltage, while diode GR16 limits the meter current to about 100 µA.
All supply units are electrically stabilised by valves B5. B6 and B7 in the classic way. The 110-V voltage is supplied by B3.
The supply transformer is protected by a thermal fuse which interrupts the mains voltage if the transformer becomes too hot.
For calibrating the instrument calibration unit U2 delivers voltages of 10 mV and 3 V; the frequency of the voltage is 1000 c/s.
The R.C. oscillator consists of pentode B8' in conjunction with the capacitors C34, C35 and C36 and the resistors R81 and R82, constituting the tuning circuit. Triode B8 is connected as a diode and serves to control the amplitude of the oscillator voltage.
The 3-V calibrating voltage is adjusted by means of resistor R84 or R87 and the 10-mV calibrating voltage by means of potentiometer R92.
The output sockets "RECORDER" are provided for connection of a recorder. If a plug is inserted into one of these sockets the indicating meter is automatically cut out.
Care must be taken, however, that the sockets "RECORDER" are connected to a d.c. voltage with respect to earth. This means that the connection of the recorder must be made free from carth.
At sockets "OUTPUT" the input signal (B13') amplified by channel 2 is available. This output signal is given a specific value by the cathode follower.
The output is independent of the test amplifier and the measuring procedure cannot be interfered with by external influences.
Fig. 9. Removing the knob
The cabinet consists of a number of separate panels that can be removed one by one.
The amplifier voltmeter PM 2520 requires little maintenance, as the instrument does not contain parts that are really liable to wear. If necessary, the switch shaft can be lubricated with some thinly fluid oil (sewing-machine oil).
The switch contacts may only be treated with a special switch oil in the case of break down. (The ordering number of this oil is stated in the list of mechanical parts).
The panels are made of aluminium coated with a layer of P.V.C. and can be cleaned with water and soap after having been detached.
ltem to be adjusted | Adjusting | Required | Recommended | ||
---|---|---|---|---|---|
devices | auxiliary apparatus | PHILIPS apparatus | |||
Stabilised d.c. voltage | R 70 | Valve voltmeter | GM 6020 | ||
Electrical zero-adjustment | R31 | none | |||
Sensitivity | R37 |
L.F. generator
Valve-voltmeter |
GM 2317
GM 6012 (calibrated) |
||
Frequency-response curve | СП, СП |
Ł.F. generator
H.F. generator |
ZV 2312
GM 2883 |
||
Pre-attenuator | R3, R103 | L.F. generator | GM 2317 | ||
C1, C101 | Valve-voltmeter | GM 6012 (calibrated) | |||
Calibrated-voltage generator | R84. R87 | L.F. generator | GM 2317 | ||
R92 | Valve-voltmeter | GM 6012 (calibrated) | |||
Common mode rejection | R58, R93 | L.F. generator | GM 2317 | ||
R98, R99 | Valve-voltmeter | GM 6012 (calibrated) |
The above sequence is completely arbitrary. The sequence stated in Chapter XI is recommended for complete adjustment.
The tolerances stated below are factory tolerances which apply to the readjustment of the instrument. They may differ from the data stated in the "General Part" (point III).
In Chapter X all adjusting devices, selector resistors and selector capacitors are stated and their functions are described; this chapter also contains a survey of the auxiliary equipment required.
Adjust the mains voltage to 220 V. + or - 1 % by means of a variable transformer or a stabilizer.
Measure the voltage with respect to earth on point 7 of unit U4. It must be 215 V. + or - 2%. If necessary, select another value for R70.
Set the mains switch to position "~".
The apparatus remains switched on during all following test measurements.
The heating-up time is at least 15 minutes.
The meter indication must now also be 100. If necessary, check the zero adjustment.
Fig. 10. Bottom view of interior
freq | uency of input signal | indication on the meter | ||||
---|---|---|---|---|---|---|
10 | c/s | 97103 | ||||
20 | c/s | 99101 | ||||
100 | c/s | 99101 | ||||
1 | kc/s | 100 reference point | ||||
10 | kc/s | 99101 | ||||
100 | kc/s *) | 99101 | ||||
200 | kc/s *) | 99101 | ||||
500 | kc/s *) | 9810 2 | ||||
1 | Mc/s *) | 97103 | ||||
*) These four ranges must also be checked in the positions, "1 mV", "3 mV", "30 mV" and "3 V" of the measuring-range switch.
Fig. 11. Right-hand side view
can now be read at option, so that it is possible to compare both voltages.
Adjust the internal calibrating voltage by means of the selector resistor R84 or R87 so that it is equal to the external voltage within 0.3% (Fig. 12).
Check the internal 10-mV calibrating voltage in the same way using an external calibrating voltage of 10 mV.
The adjustment is effected by means of potentiometer R92 (Fig. 12).
- Check the oscillation frequency and the wave form by means of a calibrated oscilloscope (frequency limits 800...1200 c/s).
Set the measuring-range switch to position "1 mV".
Set the measuring-range switch to position "10 mV".
Adjust the indication of the meter to 100 by means of an external constant voltage.
Vary the mains voltage by + and -10%.
At intervals of 1 minute the deflection of the pointer must not deviate more than half a scale division.
Fig. 12. Left-hand side view
The maximum deflection in both extreme positions of the potentiometer must have approximately the same value.
If this should not be the case, the preceding adjusting points must be checked.
The network for indication of the r.m.s. value can be checked best by comparing this indication with the indication of a thermocouple instrument. If such an instrument is not available, it is also possible to carry out a comparative measurement with another calibrated PM 2520. Should differences be found, possible tolerance overlaps must be taken into account, however.
Apply pulses to the left-hand input socket "1 mV – 300 V" and to terminal "#" by means of a square-wave generator. The pulses must be so strong that full-scale deflection is obtained, while the iterative frequency must be 1000 c/s.
Fig. 13. Pulse shape
The deviation from the indication of a calibrated thermo-couple instrument must not exceed 4 %.
A defective diode in the network can be readily detected by measuring the blocking and forward resistances. A simple way of doing this is to use an ohmmeter; the diode need not be removed from the circuit.
Connect a voltage of such a value that the instrument shows full-scale deflection.
Connect a millivoltmeter with a high input impedance (Ri ≥ 100 kΩ) free from earth to the sockets "RECORDER" at the rear of the instrument. The indication of this instrument must lie between 95 and 105 mV d.c.
- Check whether the indicating meter is cut out when a plug is inserted into one of the sockets "RECORDER".
The parts used in the manufacture of the instrument have not been specially selected or given a particular value.
When replacing electrical components the data stated in the parts list must be strictly adhered to, as otherwise the accuracy of the instrument will be affected.
For the accessibility of the parts, see Chapter II.
When this fuse blows, the cause of this blowing must be traced before replacing the fuse.
Fitting a new thermal fuse.
Fit the thermal fuse to the spring and pull it over the hook on the transformer. The fuse becomes accessible after removing the cover.
In the case of replacement the valves must be aged for 100 hours. The simplest way of doing this is to leave the instrument with the new valves switched on for 100 hours.
The valves can also be aged outside the instrument, however. For this purpose the valves are connected as diodes; all grids are then connected to the anode of the relevant system. The anode voltage is selected so that at normal heater voltage a quiescent current of 1/6 × the maximum permissible cathode current flows. This quiescent current has the following values for the various types of valve:
B1/11 | PCF80 == 2.3 mA Both pentode and |
---|---|
triode | |
B2/12: B3/13; B4/14 | ECF80 = 2.3 mA ditto |
B8 | E80CF = 3 mA ditto |
B6 | EF86 = 1 mA |
B5 | EL86 = 1.6 mA |
B7 | 85A2 = 1.6 mA |
Valve | Chapter XI, paragraph | ||||
---|---|---|---|---|---|
B1/11, B2/12, B3/13, B4/14
B5, B6, B7 |
= A, B, H
= A, B |
||||
B8 | = E |
For the replacement of diodes no special measures are required. In this case as well it is recommended to check the relevant part of the circuit.
In principle the same method should be adopted for replacing the text-plate as the one described under D.
Remove the cover, the bottom plate and the side panels.
When carrying out repairs on switches always see to it that the wire forms are not displaced or deformed.
This also applies to the arrangement of the resistors fitted to the switch.
Such changes will cause capacitive variations and have a detrimental effect on the frequency-response curve of the instrument.
It is recommended in any case to check the instrument according to Chapter XI and, if necessary, to adjust it again, after the measuring-range switch has been taken apart.
The following voltage values apply to an average apparatus and are given for your information only.
The supply transformer and its connection diagram are shown in Fig. 14.
The voltage values in the relevant table have been measured at no load.
The numbers stated between brackets represent the wire colours according to the international resistor colour code.
The principal operating voltages of the instrument are stated in the circuit diagram. These voltages have been measured with respect to earth or between the indicated connecting points by means of a valve-voltmeter.
Fig. 14. Mains-transformer
– Minimum basic | sic stock | ||||||||
---|---|---|---|---|---|---|---|---|---|
Fig. | Item | Number | Code number | Description | S for | 1 | 3 | 5 | 10 apparatus |
15 | 1 | I | ZD 202 84 | Instruction plate | ** | - | ł | ||
3 | 2 | 1 | M7 076 17 | Grip | 44 | - | _ | 1 | |
3 | 3 | 2 | E2 742 67 | Bracket | ** | - | _ | 2 | |
15 | .1 | 1 | P5/560/16/NB | Lens | ** | - | I | ||
16 | 5 | 1 | M7 751 78 | Switch socket | * | i | 2 | 3 | 5 |
15 | 6 | 1 | 973/53 | Knob 30 mm dia. | ı k | i | 2 | 2 | 3 |
15 | 7 | I | 973/D52 | Cap for knob | ** | • | I | 1 | [ |
15 | 8 | I | 973/P51 | Arrow head for knob | ** | - | _ | 1 | 2 |
15 | 9 | 3 | M7 694 87 | Terminal | * | 1 | 2 | 3 | 5 |
15 | 10 | 1 | 08 521 10 | Mains switch | * | - | t | 1 | 2 |
16 | П | I | M7 415 67 | Lamp holder | ٠ | - | _ | _ | 1 |
15 | 12 | 4 | P5 655 14 | Rubber stud | * * | - | 2 | 4 | |
17 | 13 | I | M7 737 11 | Voltage selector | * | - | 1 | ||
17 | 14 | 1 | 978/M2 19 | Mains connection | * | • | - | 1 | |
17 | 15 | П | 976/PW9 > 12 | Valve socket, noval | * | ב | .4 | ( ) | 10 |
17 | 16 | ŧ | 976/PW7 - 10 | Valve socket, miniature | * | I | 2 | ||
17 | 1 | ZD 413 40 | Print UT (left) | * | |||||
18 | ť | ZD 412 94 | Print U2 | * | |||||
19 | l | ZD 412 99 | Print U3 | * | |||||
20 | 1 | ZD 413-04 | Print U4 | * | |||||
21 | Ι | ZD 413-26 | Print U5 | ٠ | |||||
22 | i | ZD 412 92 | Print U6 | * | |||||
23 | I. | ZÐ 413-42 | Print U1 (right) | সা | |||||
17 | 24 | 109 | A3 320 36 | Soldering tag | ** | 10 | 10 | 15 | 25 |
25 | 10 cc | 971/7t | Switch oil | ** | - | _ | _ | 10 cc | |
26 | 1 | 4822/075/00261 | Measuring instrument | শা | _ | Ι | 2 | ||
12 | 27 | 2 | 909/V9 , 4 | Base for C6/C106 | * | 1 | 1 |
-8411 | imai | DUSI | * SIOCK | |||||
---|---|---|---|---|---|---|---|---|
Pos. | Number | Code number | Description | S for | 1 | 3 | 5 | 10 apparatus |
1 | 1 | Housing | ||||||
2 | l | 4822 216 00411 | Plug pin | * | - | - | i | 2 |
3 | ב | M7 343 37 | Plug pin | * | L | 2 | 3 | |
4 | Ι | 4822 216 00407 | Mounting block | 新神 | - | - | i | 2 |
5 | ι | 4822 216 00409 | Rubber sleeve | * | - | Ι | 2 | |
6 | 1.2 m | 4822 128 00439 | Coaxial cable | 1,2 | 2,4 | 2,4 | 4.8 m | |
7 | I | 4822 216 00408 | Rubber sleeve | * | - | ] | 2 | |
8 | 2 | 978/1 × 4AP | Plug | * | - | 1 | 2 | |
' ) | l | 978/8 | Crocodile clip | * | - | - | 1 | 2 |
These should be present at the Service Department in the country concerned or at the customer's who is using the apparatus. They include:
- Components marked with one asterisk
These components generally have a long or unlimited service-life, but their presence is essential for the correct working of the apparatus. Stocking up of a few of these components depends on the following factors:
- Components marked with two asterisks
These components have a long or unlimited service-life and they are not essential for the correct working of the apparatus. Generally there is not a local stock.
.
Only non-standardised parts are stated in the electrical parts list. In the circuit diagram the standard components are indicated by means of identification marks, each representing a certain number. A list of marks with corresponding numbers is provided on the diagram. The order number of a certain standard part may be determined as follows:
is ordered under number 901/120K. is ordered under number 904/4E7.
The correct values of the adjustment resistors and capacitors have been fixed during adjustment at the factory.
All resistors are vaporised carbon resistors, unless otherwise stated.
Item | Unit | Code nu | mber | ŀ' | alue | Volt | Description | ||
---|---|---|---|---|---|---|---|---|---|
C3 | : | l i 3 | C 435 E | )F/H320 | 320 | μF | 64 | Electrolytic | |
C5 | 1 | U 3 | 909/X16 | I | 16 | μF | 40 | Flectrolytic | |
C6/C106 | I | UB | 909/A40 | ю | 400 | μF | 4 | Electrolytic | |
C8 | I | U 5 | AC 8324 | 4/100 | 100 | μF | 150 | Electrolytic | |
C10/C110 | ł | U 5 | 909/T64 | 0 | 640 | μF | 4 | Electrolytic | |
C12 | ١ | U 6 | C 426 A | E/G12.5 | 12.5 | քե | 25 | Electrolytic | |
C13/C14 | ļ | U 4 | C 435 D | F/F800 | 800 | μl ; | 25 | Electrolytic | |
C15/C16 | I | U 4 | AC 8209 | 9/16 - 16 | 10 | 5 - 16 | μF | 4(X) | Electrolytic |
C17/C18 | l | L! 4 | AC 8209 | 9/16 - 16 | Ie | n4 16 | μF | 400 | Electrolytic |
C21/C22 | I | L' 4 | AC 8220 | 5/25 + 25 | 23 | - 25 | μF | 250 | Electrolytic |
C23/C24 | l | 13 | AC 8220 | 5/25 - 25 | 25 | 55 25 | μI ∓ | 250 | Electrolytic |
C41 | 1 | LU -4 | AC 860. | 3/25 | 25 | μF | 100 | Electrolytic | |
Resistor | S | ||||||||
liem – | Unit | Codenum | ner | Value | Watt | Tol. | Description | ||
R3/R103 | ιı | F 088 DG | i:10AO3 | 5 | kΩ lin. | 0.1 | 20 ", | Carbon pot | entiometer |
R8/R108 | υī | 48 063 95 | 4K.55 | 1550 | Ω | 0.4 | 0.5% | Wire-wound | l resistor |
R10/R110 | U 1 | 48 760 95, | 155E | 155 | Ω | 0.4 | 0.5% | Wire-wound | l resistor |
R11/R111 | U 1 | 48 760 95 | /49E | 49 | Ω | 0.4 | 0.5 "; | Wire-wound | f resistor |
REZ REE | U I | 48 760 95 | 22F7 | 22.7 | Ω | 0.4 | 0.5 % | Wire-wound | I resistor |
Item | Unit | Code nummer | Value | Wan | Tol. | Description | |
---|---|---|---|---|---|---|---|
R19/R119 | U 3 | B8 305 23D/190E | 190 | Ω | 0.1 | 1 " | Carbon resistor |
R26/R126 | UΤ | 48 063 95/1K 55 | 1550 | Ω | 0,4 | 0.5 ° u | Wire-wound resistor |
R28/R128 | UŁ | 48 760 95/227E | 227 | Ω | 0.4 | 0.5 ° " | Wire-wound resistor |
R31 | E 199 AA/C21B1K | l | kΩ | l | 10 | Wire-wound potentiometer | |
R37 | U 5 | 4822 071 005 84 | 5 | kΩ log. | 0,1 | 20 0 .0 | Carbon potentiometer |
R39/R139 | U 5 | 4822 070 003 21 | 43 | kΩ | I | 5 "., | Carbon resistor |
R44 | U 5 | E 003 AG/D6K2 | 6200 | Ω | ł | 5 °4 | Carbon resistor |
R45/R145 | U 5 | £ 003 AG/D15K | 7.5 | kΩ | 2 | ۵, | Carbon resistor (par.) |
R46 | U 6 | B8 305 23D/55K | 55 | kΩ | 0.1 | 1 ° µ | Carbon resistor |
R 47 | U 6 | 901/82K | 41 | kΩ | 0,1 | 1 ". | Carbon resistor (par.) |
R48 | U 6 | 901/36K + /2K4 | 38400 | Ω | 0,1 | ° ا | Carbon resistor (ser.) |
R49 | U 6 | 901/10K × /11K | 21 | kΩ | 0.1 | ، ا | Carvon resistor (ser.) |
R50 | U 6 | 901/10K ±2K2 | 12200 | Ω | 0.1 | 1" | Carbon resistor (ser.) |
R51 | U 6 | 901/1K2 | |||||
B8/305/17D/1K65 | 2850 | Ω | 0.1 | I "" | Carbon resistor (ser.) | ||
R52 | U 6 | B8 305 23D/21K2 | 10600 | Ω | 0.1 | ] " | Carbon resistor (par.) |
R53 | U 6 | 901/100K /82K | 45 | Ω | 0.1 | 1 % | Carbon resistor (par.) |
R58 | U 6 | 916/GE20K | 20 | kΩ lin. | 0.125 | 20 ° n | Carbon potentiometer |
R70 | U 4 | 901/33K…1M | 33kΩ1 | ΜΩ | 0.25 | 5 "" | Adjustment resistor |
R83 | U 2 | 48 123 93/15K | 15 | kΩ | 1.2 | 1 "" | Wire-wound resistor |
R84 | U 2 | 901/5K…1M | 5kΩ1 | МΩ | 0.25 | 5 °" | Adjustment resistor |
R 85 | U 2 | 48 123 01/85K | 85 | kΩ | 1.2 | 1 "。 | Wire-wound resistor |
R86 | U 2 | B8 304 94D/34K | 34 | kΩ | 1.2 | ۳. | Wire-wound resistor |
R87 | U 2 | 901/100K1M | 0,11 | MΩ | 0.25 | 5 °a | Adjustment resistor |
R88/R89 | U 2 | 48 123 01/110K | 110 | kΩ | 1.2 | a" ا | Wire-wound resistor |
R91 | U 2 | 48 760 95/190E | 190 | Ω | 0.4 | 0 ا | Wire-wound resistor |
R92 | U 2 | 901/1KIM | TkΩT | MΩ | 0.25 | 5 "., | Adjustment resistor |
R93 | U 3 | E 088 DG/10AO3 | 5 | kΩ lin, | Carbon potentiometer | ||
R98 | UΙ | 4822 128 001 59 | 100 | Ω lin. | Carbon potentiometer | ||
R99 | U 3 | E 097 AD/1M | ł | MΩ lin. | Carbon potentiometer |
Item | Unit | Number | Туре | Description |
---|---|---|---|---|
BI/BI1 | U 3 | 2 | PCF80 | Valve (noval) |
B2/B12 | U 3 | 2 | ECF80 | Valve (noval) |
B3/B13 | U 5 | 2 | ECF80 | Valve (noval) |
B4/B 14 | U 5 | 2 | ECI-80 | Valve (noval) |
85 | U 4 | 1 | EL86 | Valve (noval) |
B6 | U 4 | 1 | EF86 | Valve (noval) |
B7 | U 4 | ł | 85A2 | Valve (miniature) |
B8 | U 2 | Ι | E80CF | Valve (noval) |
hem | Unit | Number | Турс | Description |
---|---|---|---|---|
GRI | U 5 | 1 | OA5 | Diode, gold-wire |
GR2 | U 5 | 1 | OA5 | Diode, gold-wire |
GR3 | U 5 | ł | OA5 | Diode, gold-wire |
GR4 | U 5 | Ι | OA5 | Diode, gold-wire |
GR5 | U 6 | l | OA5 | Diode, gold-wire |
GR6 | U 6 | 1 | OA5 | Diode, gold-wire |
GR7 | U 6 | 1 | OA5 | Diode, gold-wire |
GR8 | U 6 | 1 | OA5 | Diode, gold-wire |
GR9 | Uδ | 1 | OA5 | Diode, gold-wire |
GR10 | U 6 | 3 | OA5 | Diode, gold-wire |
GR11 | U 6 | 1 | OA5 | Diode, gold-wire |
GR12 | U 4 | 1 | OA214 | Silicon diode |
GR13 | U 4 | L | OA214 | Silicon diode |
GR14 | U 4 | Ι | OA214 | Silicon diode |
GR15 | U 4 | I | OA214 | Silicon diode |
GR16 | U 6 | I | O A 85 | Germanium diode |
GR17 | U 6 | 1 | OAZ213 | Zener diode |
GR18 | U 4 | 1 | OA210 | Silicon diode |
GR19 | U 4 | Ι | OA210 | Silicon diode |
Miscellaneo | DUS | |||
Description | Pos. | Code number | ||
Mains transfe | ormer | .1.1 | ZD 601 24 | |
Thermal fuse | VL1 | 974/1125 | ||
Pilot lamo | 1 A 1 | 6878 | (6 V 100 mÅ) |
Fig. 15. Bottom view of exterior
Fig. 16. Top view
PEM 1226 E 904
Fig. 17. Rear view without rear plate
Fig. 18. Switch segments
43
Fig. 21. Unit U2, calibration voltage generator
E 908
Fig. 22. Unit U3, pre-amplifier
Fig. 23. Unit U4, supply unit
Fig. 24. Unit U5, output stage
Fig. 25. Unit U6. quadratic network
Fig. 26. Measuring cable
49
Fig. 27. Circuit diagram PM 2520
Fig. 27. Circuit diagram PM 2520