TB 9-6625-132-24
(11) Slowly rotate the TI FREQUENCY Hz dial to 20 and verify the harmonics are 30 dB
or more below the peak of the fundamental signal.
(12) Set the TI MULTIPLIER to 105. Slowly rotate the TI FREQUENCY Hz dial to 2
and verify the harmonics are 30 dB or more below the peak of the fundamental signal.
(13) Set TI AMPL control to minimum.
b. Adjustments.
(1) Set TI controls as indicated in (a) through (i) below.
(a) FREQUENCY Hz
20
103
(b) MULTIPLIER
(c) FREQUENCY VERNIER
fully CW
(Square)
(e) VAR SYMM
off
(f) FREE RUN
in
(g) ATTENUATOR
0 dB
(h) AMPL (variable)
fully CW
(i) OFFSET
off
(2) Connect to audio analyzer. Set audio analyzer to measure distortion.
(3) Adjust potentiometers R1412, R1511, and R1421 (fig. 1) for a minimum reading on
audio analyzer. Repeat adjustments until no further improvement is noted. (R)
(4) Set TI MULTIPLIER to 1.
(5) Connect multimeter negative input to pin 2 of U1930 and positive input to pin 2 of
U1940.
(6) Adjusts potentiometer R1951 for a 0.0000 indication on multimeter. (R)
(8) Adjust TI FREQUENCY Hz dial to 1 and change TI MULTIPLIER to 102.
(9) Adjust potentiometer R1441 for a minimum reading on audio analyzer.
(10) No further adjustments can be made.
10