TM9-4935-294-15/2
Table 3-11. P-Band Rf Head Test Chart
Test equipment control
Rf head control
Possible cause
Step
positions or operation
positions or operation
Normal indication
of malfunction
Corrective measure
1
Set up signal source, utilizing
Set FREQUENCY-MC
Power meter indicates 5
R1505 out of adjustment
Adjust R1505 as indicated
P-band rf head under test
control to 750 MHz.
mw
or defective.
In technical TB
for leveled operation as
9-4931-296-50 or re-
shown in figure illustrating
place, if defective.
setup for signal source levee-
eking in chapter 2, section
Broken connector pin in
Replace broken pin.
II, of TM 9-4931-294-15/1.
P701 (rf head connec-
Operate signal source in
tor).
CW mode of operation and
connect 6-db fixed coaxial
Defective resistor R1507
Replace defective resistor.
attenuator in place of coax-
or R1401.
ial termination at output of
setup. Connect thermistor
Defective BWO tube.
Replace BWO tube as in-
mount-power meter combi-
dicated paragraph
nation to the 6 db attenua-
4-17.
tor and set RF LEVEL-
LEVEL ADJ control for an
indication of 5 mw on
power meter.
2
Dionect 6-b attenuator
Power meter indicates 2
Defective direction-
Replace directional
and thermistor mount and
mw.
al coupler DC101.
coupler DC101.
connect coaxial termination
to output of setup. Remove
interconnection cable from
PHASE LOCK connector,
connect thermistor mount-
power meter combination in
its place, and operate power
meter.
3
Same as 2 above.
Slowly adjust FRE-
The 2 mw indication on
R1505 out of adjustment
Adjust R1505 as indicated
QUENCY-MC control
power meter does not
or defective.
in TB 9-4931-296-50,
through its entire
vary by more than 0.5
or replace, if defective.
range.
db.
Defective BWO tube.
Replace BWO tube as in-
dicated in paragraph 4-17.
4
Disconnect thermistor mount
Adjust FREQUENCY-
Frequency measurement
Helix voltage per cir-
Adjust the circuits indi-
and replace interconnection
MC control in 50 MHz
system indications cor-
cuit out of adjustment
cated as outlined in TB
cable to the PHASE LOCK
steps, beginning at 500
respond to within 2%
or defective.
9-4931-296-50 or, if de-
connector. Connect free-
MHz, through its entire
of the frequency indi-
festive, locate and re-
Quincy measurement system
range.
cated on the rf head
place defective compo-
(refer to figure illustrating
FREQUENCY-MC
nent.
Change 1 3-34
