TM 11-5840-208-30-1
(a) Turn the MAIN POWER switch off, and turn the MAGNETRON POWER variac fully counterclockwise.
(b) Connect a voltmeter adjusted to measure at least 150 volts AC between terminal 8 of TB 1101 and terminal 3 of
TB 1102.
(c) Close interlock shorting switches S1103, S1105, and S1107 and apply main power.
(d) While waiting for the 5-minute time delay period to expire, adjust R1104 fully counterclockwise.
Caution: Make the following adjustments and observations within 60 seconds after pressing the START
button and adjusting the MAGNETRON POWER variac for 13-ma magnetron current, because operation at
lower than normal current may damage the magnetron.
(e) Press the START button, and rotate the MAGNETRON POWER variac clockwise to a magnetron current
reading of 13 milliamperes.
(f) Note the voltmeter reading (should be 120 volts). Adjust R1104 clockwise until the neon light (11101) just goes
out.
(g) Adjust the MAGNETRON POWER variac for 18 ma of magnetron current.
(h) To check the relay for proper operation, turn the transmitter off and rotate the MAGNETRON POWER variac
fully counterclockwise.
(i) Press the START button and slowly rotate the MAGNETRON POWER variac clockwise, observing the AC
voltmeter and the magnetron current meter.
(i) Note the current at which K1103 energizes; it should be between 14 and 16 millamperes.
(k) Turn the MAIN POWER switch off, and disconnect the AC voltmeter.
d. Adjustment of S1101 and S1503. See page 157 of TM 11-5840-208-20.
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