6502B RF Distribution User Guide 15247-201 Rev. B – April 2009
Warning:
To avoid serious personal injury or death,
do not
disregard warnings. All warnings use this symbol. Warnings are
installation, operation, or maintenance procedures, practices, or
statements, that if not strictly observed, may result in serious
personal injury or even death.
Caution:
To avoid personal injury,
do not
disregard cautions. All
cautions use this symbol. Cautions are installation, operation, or
maintenance procedures, practices, conditions, or statements,
that if not strictly observed, may result in damage to, or
destruction of, the equipment. Cautions are also used to indicate
a long-term health hazard.
ESD Caution:
To avoid personal injury and electrostatic discharge
(ESD) damage to equipment,
do not
disregard ESD cautions. All
ESD cautions use this symbol. ESD cautions are installation,
operation, or maintenance procedures, practices, conditions, or
statements that if not strictly observed, may result in possible
personal injury, electrostatic discharge damage to, or destruction of,
static sensitive components of the equipment.
Electrical Shock Caution:
To avoid electrical shock and possible
personal injury, do not disregard electrical shock cautions. All
electrical shock cautions use this symbol. Electrical shock cautions
are practices, procedures, or statements, that if not strictly
observed, may result in possible personal injury, electrical shock
damage to, or destruction of components of the equipment.
Recommendation:
All recommendations use this symbol.
Recommendations indicate manufacturer-tested methods or known
functionality. Recommendations contain installation, operation, or
maintenance procedures, practices, conditions, or statements, that
provide important information for optimum performance results.
Note:
All notes use this symbol. Notes contain installation, operation, or
maintenance procedures, practices, conditions, or statements, that alert you to
important information, which may make your task easier or increase your
understanding
Special Notices
Special Notices
Warnings, Cautions, Recommendations, and Notes attract attention to
essential or critical information in this guide. The types of information
included in each are explained in the following examples.
1. Hardware and embedded software - For a period of one (1) year from date of shipment by
Symmetricom, Symmetricom warrants that all Products shall be free from defects in design, material,
and workmanship; shall conform to and perform in accordance with Symmetricom's published
specifications, if any; shall be free and clear of any liens and encumbrances; and shall have good and
valid title. This warranty will survive inspection, acceptance, and payment by Buyer. Symmetricom
does not warrant that the operation of such Products will be uninterrupted or error free. This warranty
does not cover failures caused by acts of God, electrical or environmental conditions; abuse,
negligence, accident, loss or damage in transit; or improper site preparation.
This warranty shall be null and void in the event (i) Buyer or any third party attempts repair of the goods
without Symmetricom's advance written authorization, or (ii) defects are the result of improper or
inadequate maintenance by Buyer or third party; (iii) of damage to said goods by Buyer or third
party-supplied software, interfacing or supplies; (iv) of improper use (including termination of noncertified third party equipment on Symmetricom's proprietary interfaces and operation outside of the
product's specifications) by Buyer or third party; or (v) the goods are shipped to any country other than
that originally specified in the Buyer's purchase order.
Goods not meeting the foregoing warranty will be repaired or replaced, at Symmetricom's option, upon
return to Symmetricom's factory freight prepaid; provided, however that Buyer has first obtained a
return materials authorization number ("RMA Number") from Symmetricom authorizing such return.
The RMA Number shall be placed on the exterior packaging of all returns. Symmetricom will pay
shipping costs to return repaired or replacement goods to Buyer.
Symmetricom reserves the right to disallow a warranty claim following an inspection of returned
product. When a warranty claim is questioned or disallowed, Symmetricom will contact Buyer by
telephone or in writing to resolve the problem.
2. Software - Symmetricom warrants that for a period of ninety (90) days from date of shipment by
Symmetricom the accompanying media will be free from defects in materials and workmanship under
normal use. The physical media warranty does not apply to defects arising from misuse, theft,
vandalism, fire, water, acts of God or other similar perils. Symmetricom will not be liable for any
damages caused by the Buyer's failure to fulfill its responsibilities as stated above.
3. THE FOREGOING WARRANTY IS IN LIEU OF ALL OTHER WARRANTIES, EXPRESSED OR
IMPLIED, INCLUDING, BUT NOT LIMITED TO, ANY IMPLIED WARRANTIES OF TITLE,
MERCHANTABILITY, OR FITNESS FOR A PARTICULAR PURPOSE HOWSOEVER ARISING.
4. Limitation of Liability - The remedies provided herein are the Buyer's sole and exclusive
remedies. In no event or circumstances will Symmetricom be liable to Buyer for indirect, special,
incidental or consequential damages, including without limitation, loss of revenues or profits, business
interruption costs, loss of data or software restoration, or damages relating to Buyer's procurement of
substitute products or services. Except for liability for personal injury or property damage arising
from Symmetricom's negligence or willful misconduct, in no event will Symmetricom's total
cumulative liability in connection with any order hereunder or Symmetricom's Goods, from all causes of
action of any kind, including tort, contract, negligence, strict liability and breach of warranty, exceed
the total amount paid by Buyer hereunder. SOME JURISDICTIONS DO NOT ALLOW CERTAIN
LIMITATIONS OR EXCLUSIONS OF LIABILITY, SO THE ABOVE LIMITATIONS OR EXCLUSIONS
MAY NOT APPLY TO ALL BUYERS.
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6502B RF Distribution User Guide 15247-201 Rev. B – April 2009
This manual contains procedures and descriptive information for proper installation
and operation of the Symmetricom 6502B RF Distribution Module.
The 6502B RF Distribution Module takes a single output signal of a frequency
source, like a cesium frequency standard, and provides additional buffered outputs,
ten per module. this manual contains the information needed to install, configure,
and use the 6502B.
Purpose of Equipment
The Symmetricom 6502B RF Distribution Module uses Symmetricom’s high
performance distribution technology created for it’s line of cesium standards. The
1U (1.75" high) chassis houses a set of very low noise and high isolation RF
amplifiers. Up to ten Symmetricom 6502B RF Distribution Modules may be daisy
chained to provide up to 100 independently buffered outputs of the common input.
The level of the input signal and all ten output signals are monitored, providing a
visual indicator of signal presence as well as a summary fault (form-C relay) for
each module.
A complete list of performance characteristics is provided in Chapter Four.
Instrument Identification
The model number 6502B may be followed by a slash (/) and a three-digit number
to indicate an option that is supplied within the instrument.
Preparation for Shipment
To turn off the Symmetricom 6502B prior to shipment, remove the AC power from
the plug on the rear panel. Package the instrument in its original packing if possible.
If the original packing materials are not available, pack in a reinforced cardboard
carton using foam to take up any space inside the carton. Do not use foam popcorn
or crushed paper for packing.
If the instrument is being returned to Symmetricom, contact the Service Department
at (978) 927-8220 to advise of the product return.
15247-201 Rev. B – April 2009 6502B RF Distribution User Guide
The Symmetricom 6502B is designed to be mounted in a standard 19-inch
equipment rack and takes up 1 U of vertical space (1.75”). The chassis depth is 12
inches.
Power Connection/Fuses/Voltage
The Symmetricom 6502B is powered from an AC source by a detachable power
supply cord. The power cord is the disconnect device. Refer to Chapter Four for
power supply requirements. The AC fuses are located inside the AC
connector/filter. The hot and neutral lines are fused separately. To change fuses,
refer to Figure 1. Open the cover on the AC connector/filter by applying a
screwdriver to the cover slot. Once the cover is open, each fuse holder may be
removed for inspection or replacement. Replace only with a 0.2A, 250V Slow
Blow as specified in Chapter four.
Figure 1 AC Input Filter/Fuses/Voltage Selector
The Symmetricom 6502B may be powered from 100/120 or 220/240 VAC. To
change the AC input between 100/120 and 220/240 V, refer to Figure 1. Open the
cover on the AC input connector by applying a screwdriver to the cover slot. Once
the cover is open, a selector switch may be rolled left or right to line up “120” or
“240” with the small window in the connector cover. Replace the cover on the AC
input connector by snapping it in place.
15247-201 Rev. B – April 2009 6502B RF Distribution User Guide
This instrument must be operated only
as specified by the manufacturer. Use other than as
specified may compromise the safety precautions
of the system.
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6502B RF Distribution User Guide 15247-201 Rev. B – April 2009
The Symmetricom 6502B (DC version) is powered from a DC source. The
connections are made at TB1 as shown in Figure 2. The voltage input may be 20
V to 75 V.
Figure 2 DC Power Connection
Signal Connectors
Connect the signal to be distributed to one of the two BNC connectors labeled
INPUT. Set the impedance switch to 50Ω (down) if only one 6502B module is to be
used. If multiple 6502B modules are used to obtain more than ten outputs, see
Figure 4.
Output cables may be connected in any order to the BNC connectors labeled 1 to
12. Refer to Figure 3.
Figure 3 Signal Connections
With the 6502B powered, the green power indicator on the front panel will
illuminate. The impedance switch should be set to 50Ω if there is only one module.
The red indicator next to the input signal is off to show that there is a good input
signal.
Daisy Chaining More Than One Module
If more than ten outputs are required, up to ten Symmetricom 6502B modules can
be driven by a common input signal to produce up to 100 outputs. Figure 4
illustrates this connection.
15247-201 Rev. B – April 2009 6502B RF Distribution User Guide
The example in Figure 4 shows three units. The original signal from the source is
connected to the top IN connector on the right side of the first module. The lower IN
connector on the first module is connected to the top IN connector on the second
module. The second module is connected to the third module in the same fashion.
The impedance switch for the first and second chassis is set to HI Z, while the
impedance switch on the third (or last) chassis in the daisy chain is set to 50Ω.
Figure 4. Daisy Chaining Multiple Modules
Alarm Connections
The Symmetricom 6502B provides for an alarm to signal the failure of any signal
output. One set of form-C relay contacts is provided on the 9-pin D connector
labeled ALARMS. For normal operation, pins 1 to 2 are open and pins 1 to 3 are
closed. The sense is reversed for a fault condition. Refer to Figure 5.
Figure 5. Alarm Contacts
If the input signal or input buffer fails or falls below the factory-set low-level
threshold, the red fault indicator next to the input connector will turn on. Likewise, if
any output buffer fails or falls below the low-level threshold, a red fault indicator next
to that output will turn on. The ALARM form-C relay is normally energized,
indicating no signal failure. If either the input or any output signal fails, the relay is
de-energized (short between pins 1 and 2), indicating a fault condition. This is a
fail-safe design that will indicate a fault in the event of a power loss.
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6502B RF Distribution User Guide 15247-201 Rev. B – April 2009
The Symmetricom 6502B RF Distribution controls and indicators are described in
this chapter.
Figure 6: 6502B Distribution Front Panel
Figure 7: 6502B Distribution Rear Panel
Controls and Indicators
HI Z/50
This slide switch on the rear panel selects either the HI Z input impedance (unterminated) or the 50Ω input impedance. A 6502 installation of two or more (ten
maximum) units will set the switch to HI Z position on the module connected to the
source of the signal, and on all subsequent modules except the last module, which
is switched to the 50Ω position, providing proper termination for the signal.
ALARM OVERRIDE
When provided, the optional ALARM OVERRIDE toggle switch enables or disables
the ALARM relay output on the ALARM connector. This makes ALARM OVERRIDE
useful for suppressing audible alarms.
With ALARM OVERRIDE in the UP position, the ALARM relay is enabled and
changes states in the event of a signal failure. With ALARM OVERRIDE in the
DOWN position, the ALARM relay is disabled, forcing it into a normal (no alarm)
condition. ALARM OVERRIDE doesn’t affect the LED indicators.
POWER
LED on the front panel to indicate that power is applied. There is no power switch on
the 6502B. When power is connected, power is ON.
Ω
15247-201 Rev. B – April 2009 6502B RF Distribution User Guide
LED on the front panel to indicate that an ALARM condition exists. An alarm
condition exists when the input signal or any output signal fails or falls below the
factory preset amplitude.
INPUT FAULT
This LED is located on the rear panel between the two INPUT connectors. If the
input signal fails or falls below the factory preset amplitude, this LED will light and
stay on until the cause of the fault is remedied.
OUTPUT FAULT
There are ten LED indicators, located to the right of each output connector. If any
output signal fails or falls below the factory preset amplitude, the LED associated
with the failed output will light and stay on until the cause of the fault is remedied.
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6502B RF Distribution User Guide 15247-201 Rev. B – April 2009
If the input signal level is less than 10 dBm, please specify
the Low Alarm Threshold version (-509).
Specifications
Power
Power
Operating Voltage 100 – 120 / 180 - 240 VAC, ±10%, 50/60 Hz,, 0.1/0.05 A <10 W
DC Input (Optional) 22 to 56 VDC, 10 W
Fuse Type Little fuse, slow blow, 2/10A, 250V, 5x20mm
Operating Temperature 0 to 55°C
Relative Humidity 0 to 95%, non-condensing
Overvoltage Category II
Pollution Degree 2
Intended for INDOOR USE ONLY
Altitude Up to 2000 M
Alarm Output
Summary alarm indicates failure of any output signal.
Each Output & Main Red LED
Non-alarm Condition Relay energized (fail safe) Form-C Contacts
14364-101 Standard configuration, AC input
14364-102 Standard configuration, DC input
14364-109 OdBM Input threshold, DC input
14364-116 Standard configuration, AC input,
rear-panel ALARM OVERRIDE switch
Specifications Available Versions
15247-201 Rev. B – April 2009 6502B RF Distribution User Guide