TM9-4935-294-15/2
Table 3-17. K-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 FREOUENCY-MC
Power meter indicates 1
R1505 out of adjustment
Adjust R1505 as indicated
K-band rf head under test
control to 22.250 MHz.
mw.
or defective.
in technical bulletin TB
for leveled operation as
9-4931-301-50,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, but
do not remove the second
Defective resistor R1507,
Replace defective compo-
directional coupler. Connect
R1401, R1402 or choke
nent.
thermistor mount-power
L1401.
meter combination to the
second directional coupler
Defective BWO tube.
Replace BWO tube as in-
and set RFLEVEL-
dicated in paragraph
LEVEL ADJ control for an
4-22.
indication of 0.5 mw on
power meter.
2
Same as 1 above
Slowly adjust FRE-
The 1 mw indication on
R1505 out of adjustment
Adjust R1505 as indicated
QUENCY-MC control
power meter does not
or defective.
in TB 9-4931-301-50,
through its entire
vary by more than 2.5
or replace, if defective.
range.
db.
Defective BWO tube.
Replace BWO tube as in-
dicated in paragraph
4-22.
3
Disconnect thermistor mount
Adjust FREQUENCY-
Signal source phase-locks
Mixer diode CR101 defec-
Replace mixer diode
from directional coupler.
MC control in 850 MHz
as indicated on tunable
tive.
CR101.
Connect frequency measure-
steps, beginning at
synchronizer.
Ment system(refer to
18, 000 MHz, through its
Directional coupler CP101
Replace directional cou-
figure illustrating setups
entire range.
defective.
pler CP101.
for frequency measurement
of an active source above
Frequency measurement
Helix voltage-shaper cir-
Adjust the circuits indi-
12.4 GHz in chapter 2, sec-
system indications cor-
cuit out of adjustment
cated as outlined in TB
tion III, of TM
respond to within 2% of
or defective.
9-4931-301-0 or, if de-
9-4931-294-15/1) to the
the frequency indicated
defective, locate and re-
auxiliary arm of the second
on the rf head FRE-
place defective compo-
directional coupler in the
QUENCY-MC counter.
nent.
setup. Phase-lock signal
source at each of the 11 fre-
HV limit circuit (R1403,
quency settings.
R1404 and R1405) out
of adjustment or defec-
tive.
3-65
