TB 9-6625-967-35
12. Input Capacitance and VOLTS/DIV Switch Compensation
a. Performance Check
(1) Connect square-wave generator (A7) output to TI CH1 input, using cables and
termination supplied with square-wave generator, standardizer (B6) and adapters (B1 and
B2) (AN/GSM-256 use cable (B4)).
(2) Adjust time base plug-in (A8) for a .2 millisecond sweep.
(3) Turn TI CH1 and CH2 VOLTS/DIV switches to .01 and set CH1 and CH2 AC-
DC-GND switches to DC.
(4) Adjust square-wave generator frequency to 1 kHz and amplitude for 4 major
divisions of vertical deflection on oscilloscope (A5) crt. If square-wave display does not have
flat tops, adjust standardizer for optimum square wave with flat tops. If optimum square
wave cannot be obtained, adjust C111 (fig. 1) to midrange and readjust standardizer. For
CH2, adjust C211 (fig. 1) instead of standardizer.
(5) Repeat technique of (3) and (4) above for TI VOLTS/DIV switch settings and
display on oscilloscope crt.
Table 5. VOLTS/DIV Switch Compensation
Test Instrument
Adjustments (fig. 1)
VOLTS/DIV
Channel 1
Channel 2
switch setting
square corner
Flat top
Square corner
Flat top
.02
---
C112 (R)
---
C212 (R)
.05
C103C (R)
C103B (R)
C203C (R)
C203B (R)
.1
C105C (R)
C105B (R)
C205C (R)
C205B (R)
.2
C107C (R)
C107B (R)
C207C (R)
C207B (R)
2
C109C (R)
C109B (R)
C209C (R)
C209B (R)
(6) Remove square-wave generator connection from TI CH1 and connect to CH2
input.
(7) Turn TI MODE switch to CH2 and repeat (4) and (5) above for CH2.
b. Adjustments. No further adjustments can be made.
13. High-Frequency Compensation and Rise Time
a. Performance Check
(1) Connect square-wave generator (A7) to TI CH1, using cable and termination
supplied with square-wave generator (AN/GSM-256 use cable (B4)).
(2) Turn TI CH1 and CH2 VOLTS/DIV switches to .01 and MODE switch to CH1.
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