Electro-Metrics EM-2115, Инструкция по эксплуатации

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ELECTRO-METRICS EM-2115 2.0 OPERATING INSTRUCTIONS
(EM2115S2-27)
e. Tune the EM-2115 to the mid-range point of the frequency band range selected.
Adjust the Y-ZERO Control of the recorder to position the recorder pen so that
the noise level is slightly above the bottom margin of the chart paper.
f. Adjust the Threshold bias level for a full scale reading on the front panel analog
meter.
g. Adjust the Y-GAIN Control of the recorder to position the recorder pen over the
top margin of the chart paper.
h. Repeat Steps e thru g until no further adjustments are required.
2.6.2 EM-2115/X-Y Recorder Operation
a. Set the EM-2115 front panel controls as required for the test being performed --
e.g., Bandwidth, Detector, Attenuator, etc.
NOTE: Since the EM-2115 normally uses the Single Scan Mode of op-
eration when a X-Y plotter is being used for data recording, the
following procedure is based on the Scan Mode set for SIN-
GLE.
b. Set the Scan Width Control at the setting desired:
1) FULL CCW (FULL BAND), an intermediate setting,
2) FULL CW (MIN).
c. Set the Scan Rate Control at the setting desired:
1) FULL CCW (CAL), an intermediate setting,
2) FULL CW (MAX)
d. In conjunction with the Bandwidth Switch setting, the Scan Rate Control deter-
mines the sweep speed of the recorder as follows:
1) CAL (FULL CCW):
Maximum sweep time--slowest sweep rate. For Single Scan Mode and narrowest
bandwidth, typical sweep time is approximately 3000 seconds.
This switch position will allow the peak of a detected signal to be accurately rec-
orded. The sweep circuitry sets an optimum sweep rate (determined by the IF
bandwidth selected) which permits the external X-Y plotter to accurately record
the amplitude level of a detected signal for all IF Bandwidth Switch positions.
2) MAX (FULL CW):
Minimum sweep time--fastest sweep rate. For Single Scan Mode and widest
bandwidth, typical sweep time is approximately 30 seconds.