TB 9-6625-132-24
b. Adjustments
(1) Ensure TI controls are set as in (2) above, but set MULTIPLIER to 103.
(2) Locate the coupler holding the FREQUENCY Hz potentiometer extension shaft and
loosen the coupler set screw.
(3) Adjust the FREQUENCY Hz potentiometer until counter indicates between 19,400
Hz and 20,600 Hz. (R)
(4) While holding the potentiometer (coupler), adjust the FREQUENCY Hz dial to 20
(exact).
(5) Tighten coupler set screw.
(6) Rotate the FREQUENCY Hz dial to 18 then back to 20 and ensure counter indicates
within tolerance listed in b (3) above.
(7) No further adjustments can be made.
9. Output Amplitude and Attenuator
a. Performance Check
(1) Connect TI OUTPUT to oscilloscope channel 1 input set for 50 Ω input impedance.
(2) Set TI controls as indicated in (a) through (i) below.
(a) FREQUENCY Hz
20
103
(b) MULTIPLIER
(c) FREQUENCY VERNIER
fully CW
(d) Waveform pushbutton
(Sine)
(e) VAR SYMM
off
(f) FREE RUN
in
(g) ATTENUATOR
0 dB
(h) AMPL (variable)
fully CW
(i) OFFSET
off
(3) Oscilloscope will display an amplitude of at least 15 V p-p.
(4) Set oscilloscope input impedance to 1 MΩ, Oscilloscope will display an amplitude of at
least 30 V p-p.
(5) Adjust TI AMPL control for exactly 30 V p-p on oscilloscope.
(6) Press TI -20 dB button. The Oscilloscope display must be within 2.67 to 3.37 V p-p.
(7) Press TI -40 dB button. The Oscilloscope display must be within 0.267 to 0.337 V p-p.
(8) Press TI -60 dB button. The Oscilloscope display must be within 0.0267 to 0.0337
V p-p.
