User Guide

NHB–3
Technical Documentation
PAMS
Tuning Instructions
Original 26/97
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Tuning Instructions
General
Almost all tuning operations of the NHB–3 are carried out using the Service
software. The Service software turns the phone into the service mode, in which
the phone can be outwardly controlled via the M2BUS interface.
Tuning is based on the Service software communicating with the D/A and A/D
converters of the phone. In some instances the phone processor will also cal-
culate the required correction parameter.
The tuning values of the phone reside on the EEPROM. The Service software
enables writing the default parameters on the EEPROM (Factory Reset), in
which case all tuning steps should be carried out.
N.B. During tuning, proceed as follows:
– Take care not to damage sensitive measuring instruments with excessive
RF power, use attenuator if needed.
– Carry out all tuning steps in the shortest possible time to avoid excessive
heating of RF units.
– Perform all tuning steps in the order presented.
– Never try to mask a fault by tuning it out!