TB 9-6625-781-24
10. Input Amplifier Sensitivity
a. Performance Check
(1) Position controls as listed in (a) through (c) below:
(a) SENSITIVITY switch to .1 (50V MAX) or .1 for model 5245M.
(b) FUNCTION switch to FREQUENCY.
(c) TIME BASE switch to 10 ms.
NOTE
On models 5245L with SN prefix 628 and above, turn
-LEVEL+ control to PRESET.
(2) Connect signal generator to TI AC SIGNAL INPUT, using a 50
termination.
(3) Set TIME BASE switch to 1 ms, SENSITIVITY switch to .1 (50V MAX) and
FUNCTION switch to FREQUENCY if not performed in (1) above.
(4) Adjust signal generator frequency to 50 MHz and output amplitude to minimum.
(5) Slowly increase signal generator amplitude output until a stable count is
obtained on TI. If signal generator output level indication is greater than 100 mV, perform
b below.
(6) Repeat (4) and (5) above at 10 MHz.
b. Adjustments
(1) Adjust signal generator amplitude output to 100 mV.
(2) Adjust A19R20 or A19R7 (fig. 2) until a stable count is obtained on TI (R).
Figure 2. Electronic counter - bottom view.