Electro-Metrics EM-2115, Instruction Manual

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EM-2115 4.0 SERVICE, MAINTENANCE, CALIBRATION
(EM2115S4-12)
j. Monitoring the voltage on A8-16, switch the Detector to Peak. The voltmeter
should indicate 0.00 VDC.
k. Monitoring the voltage on A8-16, switch the Detector to Slideback. The voltmeter
should indicate 0.00 VDC.
l. Monitoring the voltage on A8-70, switch the Detector to Quasi-Peak. The voltme-
ter indication should decay to <0.10 VDC.
m. Monitoring the voltage on A8-70, switch the Detector to RMS and set the Sample
Time Control FULL CCW (click stop). The voltmeter indication should decay to
<0.10 VDC.
n . Monitoring the voltage on A8-70, switch the Detector to Average (Sample Time
Control FULL CCW). The voltmeter indication should decay to <0.10 VDC.
4.4.3 Log Detector Module A4 Adjustment/Verification
Equipment required: Signal Generator.
Digital Voltmeter.
10 dB Step Attenuator.
36 pin double-sided extension board (ECB-30)
a. Loosen the eight quarter turn fasteners that secure the Submodule Assembly into
the receiver.
Do not remove any of the interconnecting cables and harnesses.
b. Lift up the Submodule Assembly, lay a piece of masonite or similar material
across the receiver and set the Submodule Assembly on it, A4 Log Module side
face up. Take care not to strain or break the cabling or harness wiring.
c. Place the Detector Board (A8) onto the 36 pin double-sided extension board and
connect a Digital Voltmeter to A8-16.
d. Set the front panel controls as follows:
DETECTOR ...................................................PEAK
BANDWIDTH ...............................................9/10 kHz
ATTENUATION ...........................................0 dB
FREQUENCY RANGE .................................0.009-0.035 MHz
FREQUENCY DISPLAY ..............................0.022 MHz
e. Remove the subminiature coaxial cable from A4J4. Connect a Signal Generator
via a 10 dB Step Attenuator to A4J4. Set the Signal Generator for a 175 kHz cw
signal at an input level of +98 dB(µV) at A4J4.