R.V.R. Elettronica HC3, Manual

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HC3 - Technical and Maintenance Manual
R.V.R. Elettronica S.r.l. (Bo) Pag. 27
switch ON.
5) Decrease the power to the nominal level and check that the Overdrive
Alarm led switch off and the system works again.
5.4 UNBALANCING POWER READING CALIBRATION
To realize this callibration execute the following operations:
1) Connect to RF output of the HC3, an external by-pass wattmeter in
series to a dummy load with the necessary power for the system
considered (see as reference SETUP 2).
2) Switch ON the system.
3) Increase driver power until to obtain the nominal output power of
the system (set at 98MHz).
4) Switch the meter selector over the UNBAL. position.
5) Switch off one of the three amplifiers.
6) Adjust trimmer RV1 of the Unbalancing Power card, to measure on the
front panel the difference power equal Antenna Power minus (sum
power of two functioning amplifiers).
5.5 UNBALANCING POWER THRESHOLD CALIBRATION
To realize this callibration execute the following operations:
1) Connect to RF output of the HC3, an external by-pass wattmeter in
series to a dummy load with the necessary power to the system
considered (see as reference SETUP 3).
SETUP 2