Electro-Metrics EM-2115, Instruction Manual

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EM-2115 4.0 SERVICE, MAINTENANCE, CALIBRATION
(EM2115S4-8)
Equipment required: Digital Voltmeter.
36 pin double-sided extension board (ECB-30), one (1) required.
4.4.1.1 Regulated DC Voltage Checks
a. Set the front panel controls as follows:
DETECTOR ...................................................AVERAGE
SAMPLE TIME CONTROL .........................Mid-range
FREQUENCY RANGE .................................0.009 -0.035 MHz
FREQUENCY INDICATION .......................0.022 MHz
BANDWIDTH ...............................................9/10 kHz
ATTENUATION ...........................................40 dB
b. Measure the voltages at the following checkpoints within the receiver.
1) Remote Connector A13J2
A13J2-L: +RAW (+21.0 VDC ±3.0 VDC).
A13J2-M: -RAW (-18.5 VDC ±3.0 VDC).
A13J2-d: +12.0 VDC ±0.1 VDC.
A13J2-c: -12.0 VDC ±0.1 VDC.
A13J2-G: +5.0 VDC ±0.1 VDC.
2) RF Tuner Module A2:
A2TP-1: +12.0 VDC ±0.1 VDC.
NOTE: The +12 VDC voltage checked at this point is produced by a
separate regulator located on the A16 Interface PC Bd and use
only by the A2 RF Tuner Module. There is no variable adjust-
ment for this voltage.
A2TP-1: -6.0 VDC ±0.1 VDC.
3) Microprocessor PC Board A1A3
A1A3TP-1: +5.0 VDC ±0.1 VDC.
A1A3TP-17: -7 VDC, nominal -6.6 to -8.0 VDC.
c. The voltmeter should indicate the readings noted. If not, proceed to Section
4.4.1.2.
4.4.1.2 Power Supply Board A14A1 Adjustments