Tait T2000 SERIES II, Service Manual

Page: 44 / 150

6.2 Tuning & Adjustment
M2000-00
31/10/96 Copyright TEL
6.1 Tuning Precautions
Refer to Section 4.1 for a list of test equipment required and a suggested test set-up. The
following precautions must be observed when carrying out the alignment procedures in
this Section.
• The microprocessor shield must remain in place throughout the alignment proce-
dure, with its 3 retaining screws torqued down to 8in.lbf (0.9Nm).
To gain access to the alignment test points and adjustment controls, it is only neces-
sary to remove the top cover and logic PCB mounting screws (refer to Section 3.2.1).
• For accurate tuning, the test cable connecting the signal generator or power meter to
the T2000 must be as short as practical and fitted with a ‘mating’ BNC connector.
Do not use adaptors, ‘sniffer’ couplings, etc., which introduce changes to cable
impedance and errors in test results.
• Non-metallic tuning tools must be used for the alignment of all coil slugs. The use of
metallic tools will result in tuning errors.
Tuning tools need to be of correct size to avoid the damage to coil slugs.
• The RF PA and audio output IC have a direct unswitched supply, and are therefore
not controlled by the control head on/off switch. This switch removes power only
from the regulated supplies.
Caution:
Under certain circumstances the microprocessor can key the transmitter.
Ensure that all instruments are protected from accidental PTT at all times.