TM 9-4935-294-15/2
Table 3-1l. S-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
S-band rf head under test
control to 3000 MHz.
mw.
or defective.
in technical bulletin TB
for leveled operation as
9-4931-298-50 or re-
shown in figure illustrating
place, if defective.
setup for signal source lev-
eling 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 6db 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 in paragraph
nation to the 6-db attenua-
4-19.
tor and set RF LEVEL-
LEVEL ADJ control for an
indication of 5 mw on
power meter.
2
Disconnect 6-db attenuator
Power meter indicates
Defective directional
Replace directional
and thermistor mount and
0.2 mw.
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 0.2 mw indication on
R1505 out of adjustment
Adjust R1505 as indicated
QUENCY-Mc control
power meter does not
or defective.
in TB 9-4931-298-50 or
through its entire
vary by more than 0.5
replace, if defective.
range.
db.
Defective BWO tube.
Replace BWO tube as in-
dicated in paragraph
4-19.
4
Disconnect thermistor mount
Adjust FREQUENCY-
Frequency measurement
Helix voltage-shaper cir-
Adjust the circuits indi-
and replace interconnection
MC control in 200 MHz
system indications cor-
cuit out of adjustment
cated as outlined in TB
cable to the PHASE LOCK
steps, beginning at 2000
responds to within 2%
or defective.
9-4931-298-50 or, if de-
connector. Connect free-
MHz, through its entire
of the frequency indi-
fective, locate and re-
Quincy measurement system
range.
cated on the rf head
place defective
(refer to figure illustrating
FREQUENCY-MC
component..
setups for f frequency me
counter.
Change 1 3-45
