R.V.R. Elettronica HC3, Manual

Page: 26 / 64

HC3 - Technical and Maintenance Manual
R.V.R. Elettronica S.r.l. (Bo) Pag. 26
CHAPTER 5
CALIBRATION PROCEDURES
5.1 INTRODUCTION
This chapter describes the calibration procedures that are necessary to
do when you have replaced some cards or some devices, or in case of a complete
replacement of the equipment into of a transmitter station.
All calibrations must be executed switching on all equipment at the minimum
power.
5.2 METER CALIBRATION
To realize this callibration execute the following operations:
1) Turn the Meter selector on the CALL position.
2) Adjust the trimmer R14 on the Alarms card for a full scale reading
on the analog meter.
5.3 OVERDRIVE 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 1).
2) Switch ON the system.
3) Increase driver power until to obtain an output power greater of
5% than nominal output power of the system.
4) Adjust trimmer R26 on the Alarms card until the overdrive Alarm led
SETUP 1