TM9-4935-294-15/2
Table 3-7
Step
Procedure
Normal indication
Possible cause of malfunction
Corrective measure
17
Repeat 14 through 16 above until
Adjustment of stub does not reduce
Defect within tuner no. 1.
Replace tuner no. 1.
stub being tuned does not re-
meter excursions any further.
duce meter needle excursions
any further.
18
Adjust stub closest to signal
Meter deviation is reduced to one-
Defect within tuner no. 1.
Replace tuner no. 1.
source to reduce meter devia-
half of its value.
tion caused by the adjustment
of the sliding short to one-half
of its value.
19
Repeat 14 through 18 above for
Deviation of indication on SWR
Defect within tuner no. 1.
Replace tuner no. 1.
each succeeding stub on tuner
meter of 0.25 db or less.
no. 1 until a movement of the
Poor connection in test setup.
Locate and correct poor or -
sliding short causes a meter
improper connection in test -
deviation of not more than
up.
0.25 db on the EXPAND scale
of the SWR meter. Secure
tuner no. 1 in this position.
20
Replace sliding short with slid-
Variations of readings on SWR
Poor or improper connection in
Locate and correct poor or
ing termination and recheck
meter of 0.75 db or less.
test setup.
proper connection in test up.
tuner no. 2 stub setting. If
necessary, readjust tuner no. 2
until meter indicates as de-
scribed in 11 above.
21
With sliding short connected to
SWR meter indicates 0 DB.
Defect within SWR meter.
Refer to SWR meter manual.
test setup, set RANGE-DB
switch to 20 (or other suitable
Poor connection in test setup.
Locate and correct poor
range); set sliding short for
connection in test setup
maximum deflection to the
right on SWR meter, and ad-
just GAIN and VERNIER
controls for 0 DB indication.
Do not change SWR meter
GAIN, BAND WIDTH, or
FREQ control settings or
BWO power supply SQUARE
WAVE FREQ control setting
during the remainder of this
procedure.
22
Remove sliding short from test
SWR meter indicates reflection co-
Poor connection in test setup.
Locate and correct poor
connection in test setup
setup and replace it with unit
efficient in db of unit under test.
under test (unknown load),
using suitable adapter(s), if
Defect within unit under test.
Troubleshoot unit under test.
required. If meter needle goes
off-scale, rotate RANGE-DB
switch cw until meter needle
reads on-scale. Note reading
3-19
