Electro-Metrics EM-2115, Instruction Manual

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EM-2115 4.0 SERVICE, MAINTENANCE, CALIBRATION
(EM2115S4-1)
SECTION IV
EM-2115
SERVICE, MAINTENANCE, AND CALIBRATION

READ THIS FIRST

1. For a listing of the test equipment required for troubleshooting and per-
forming the calibration--alignment procedures, refer to Appendix F.
2. All adjustments are limited to those made using variable components, i.e.
potentiometers, variable capacitors, variable chokes, etc. If the following
procedures CANNOT define or pinpoint the areas of malfunction or align
the receiver within the stated specification limits, contact Electro-Metrics.
4.1 Precautions
a. Verify that the Power Source selector card is correct for the AC power source be-
ing used (e.g. 120 VAC). Operation on 220 VAC with the selector card set for 120
VAC can cause extensive circuit damage.
b. Whenever the receiver is connected to the AC power source, the AC power source
voltage is present on the front panel power switch.
c. Use caution when making "power on" measurements to prevent inadvertent shorts
and possible damage to circuit components.
d. To prevent possible damage to circuitry and components, always turn off and dis-
connect the AC power source whenever removing--replacing--servicing modules,
subassemblies, PC boards, or components within the receiver.
e. The Microprocessor Board (A1A3) contains components (IC's, ROM's, etc.) that
are susceptible to Electrostatic Discharge (ESD) damage. Use care when handling
and removing the board from the receiver. Perform all Microprocessor Board re-
pairs only on a surface that is grounded to drain static charges. Ground the person
working on the board through the use of wrist straps or similar static grounding
systems. When being returned to Electro-Metrics, pack the board in protective
packaging that protects against ESD damage. Take similar precautions for board
storage outside the receiver. Contact Electro-Metrics for any information or assis-
tance required to prevent ESD damage.