Electro-Metrics EM-2115, Instruction Manual

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EM-2115 4.0 SERVICE, MAINTENANCE, CALIBRATION
(EM2115S4-22)
a. Place the Tune Control Board (A10) onto the 36 pin double-sided extension
board.
b. Set the front panel controls as follows:
DETECTOR ...................................................PEAK
BANDWIDTH ...............................................Wideband position of the frequency
range selected.
ATTENUATION ...........................................0 dB
FREQUENCY RANGE .................................0.009-0.035 MHz.
FREQUENCY DISPLAY ..............................0.022 MHz
NOTE: 1) The voltages measured in Steps c and d are the precision
reference voltages for all receiver tuning functions. Read-
justment is not recommended unless the Power Supply
Board (A4A1) or the DC regulators have been re-
placed/epaired.
2) A10-R82 sets both -8.0 VDC and +8.0 VDC reference
voltages.
c. Using a Digital Voltmeter, measure the voltage on A10-11/12. The voltmeter
should indicate -8.0 ±0.1 VDC. If not, adjust A10-R82.
d. Measure the voltage on A10-23/24, the voltmeter should in8.0 ±0.1 VDC.
e. Monitoring the voltage on A10-31/32, vary the Main Tuning Control from FULL
CCW to FULL CW. The voltmeter should vary from -8.0 VDC to +8.0 VDC ±0.1
VDC.
f. Connect the Digital Voltmeter between A10U3-6 (positive lead) and ground. Set
the Main Tuning Control FULL CW, the voltmeter should indicate -4.50 VDC
±0.01 VDC. If not, adjust A10-R14.
g. Set the Main Tuning Control FULL CCW, the voltmeter should indicate 0.00
VDC ±0.01 VDC. If not, adjust A10-R16.
h. Repeat Steps f and g until no further adjustments are required.
i. Monitoring the voltage on A10-53/54, set the Main Tuning Control FULL CW.
The voltmeter should in8.0 VDC ±0.1 VDC. If not, adjust A10-R25.
j. Set the Main Tuning Control FULL CCW, the voltmeter should indicate 0.00
VDC ±0.01 VDC. If not, adjust A10-R16.