TB 9-6625-862-35
(3) While maintaining OUTPUT LEVEL meter indication recorded in (2) above, set
FREQUENCY RANGE switch and
FREQUENCY dial
for 40 Hz,
200 Hz, 2 kHz, and 20
kHz. Multimeter indication will be between 23.12 and 32.66 V.
(4) Adjust AMPLITUDE (OUTPUT) control to 0.
b. Adjustments. No adjustments can be made.
a. Performance Check
(1) Connect INPUT connector to INPUT ground connector.
(2) Adjust zero adjustment screw on INPUT LEVEL meter for a 0 V indication.
(3) Remove test lead from INPUT connectors.
(4) Position controls as listed in (a) through (g) below:
(a)
INPUT ATTENUATOR (DB) (INPUT DB) switch to 0.
(b)
OUTPUT ATTENUATOR (DB) (OUTPUT DB) 0 to 100 switch to 30.
(c)
OUTPUT ATTENUATOR (DB) (OUTPUT DB) 0 to 10 switch to 6.
(d)
LOAD switch to OFF.
(e)
(f)
(g)
FREQUENCY dial to 40.
(5) Connect multimeter between INPUT connector and INPUT ground connector.
(6) Connect upper INPUT connector to upper OUTPUT connector.
(7) Adjust AMPLITUDE (OUTPUT) control for a 2.0 V indication on INPUT
LEVEL meter. If
multimeter does not
indicate between 1.9 and
2.1 V
ac, perform b below.
(8) Repeat technique of (7) above while adjusting AMPLITUDE (OUTPUT) control
for INPUT LEVEL meter indications listed in table 8. Multimeter indications will be
within limits specified.
Table 8. Input Level Meter Linearity Check
Multimeter indications (V ac)
Test instrument INPUT LEVEL
meter indications
Min
Max
1.5
1.4
1.6
1.0
0.9
1.1
0.5
0.4
0.6
(9) Adjust AMPLITUDE (OUTPUT) control to 0.
b. Adjustments
(1) Adjust AMPLITUDE (OUTPUT) control for a 2.0 V ac indication on
multimeter.
(2) Adjust R47 (fig. 2) (R62 (fig. 3) on TS-421C/U and model F370A) for a 2.0 V ac
indication on INPUT LEVEL meter (R).