TM 11-6625-847-45
ground on the test set. Connect the clips at the
i. Rotate the SERV SEL switch on the test set to
remaining end of cable W22 to terminal A1E11 (+20
OFF. Set the test set POWER switch to OFF, and
volts dc) and to A1E8 (ground) on tray A1A2 (fig. 4-6),
disconnect All test equipment. Replace the bottom
and connect a jumper wire from terminal A1E11 to
cover, and secure it with the screws removed in b
terminal A1E4.
above.
d. Using test cable W25, connect the rf output
connector of Generator, Signal AN/GRM-50 to terminal
A1E3. Ground the AN/GRM50 to terminal A1E2. Set
the output of the AN/ GRM-50 at terminal A1E3 to 1 mv.
a. The proper relationship between-the position of
e. Connect the AN/URM-145 to the RCVR IF test
the 10 & 1 KC SYNTH and 100 KC SYNTH module
couplers are the associated FREQ SELECT knob
connector and AMPL IF OUT on tray A1A2.
position is required to provide the proper operating
f. Set the test set POWER switch to ON, and
frequency of the plug-in module when installed on tray
rotate the SERV SEL switch to OVEN ON.
A1A2. The couplers notch should be positioned at 3
g. With the ME-26(*)/U, adjust the voltage at
o'clock when viewed from the front of the chassis, and
terminal A1E11 (fig. 4-6) for +20 volts dc, using the DC
the associated knob at 0. Establish this relationship by
VOLTAGE 20 control on the test set to adjust the level.
first rotating the knob until the coupler is positioned
properly, then loosening the Allen setscrews on the
AN/GRM-50 indicates a gain of 20 0.6 db at the output
knob, repositioning the knob to 0, and retightening the
of if. amplifier Subassembly A2.
Allen setscrews.
b. To adjust the drive chain tension, loosen the
Note. With a 1-mv input level a 20-bd gain amplifier
nuts seeming the idler assembly until the chain is firm
will indicate with equal input and output impedance,
but not taut. When the proper drive chain tension is
an output voltage level of 10 mv.
attained, tighten the nub securing the idler assembly in
position.
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