Miteq D-9301, Руководство по эксплуатации и обслуживанию, Страница: 52 / 86

5-3
5.2.2 GAIN OF THE CONVERTER
The following procedure is to be followed for gain measurements.
Connect the test equipment as shown in Figure 5-1. Set the
sweeper to cover the required input frequency range. Set the
attenuator on the log memory scope to 000 and memorize the input
reference. Connect the converter into the test setup.
Record the gain and frequency response of the converter.
The gain of the converter should be periodically monitored to
reveal deviations which would indicate possible malfunction.
5.2.3 FREQUENCY MEASUREMENT
Frequency accuracy of the converter is determined by the
reference source used. Frequency may be monitored at the rear
panel LO test points.
5.2.4 LOCAL OSCILLATOR PHASE LOCK TEST POINT (Phase Voltage)
The phase lock test point (phase voltage) of the phase lock
source indicates proper locking conditions and frequency for the
basic voltage-tuned oscillator. The following voltages will be
observed at 25°C ambient:
A. IF-LO: 10 ±2 volts "in lock"
1 volt or 18 volts
"out-of-lock"
B. RF-LO: Variable with frequency
Due to the nature of multiple loop frequency synthesizers, the
test point may not always indicate an out-of-lock state. The
front panel LED represents a summary of the individual phase lock
loop alarms.
Data on test point voltage should be recorded in a log and
compared to the original data so that changes in data as a
function of time can be observed.