Oscillator Alignment and Tracking Adjustment.

TM 11-5820-509-35

(14) Repeat steps (12) and (13) until both

f. Oscillator Alignment and Tracking Adjustment.

frequency settings are within the 1 kHz limit specified.

(1) On the test fixture, place the POWER

(15) On the indexing fixture, set the switch to 4

ON-OFF switch to OFF and the LOOP SEL switch to

and rotate the slug rack control to 000. Adjust inductor

OPEN.

L137 (fig. 3-105) until the vfo output is 4,500 1 kHz.

(2) Remove the module from the test fixture

(16) Rotate the slug rack control on the

and adjust capacitor C344 (fig. 3-98) to its mechanical

indexing fixture to the 999 position and adjust inductor

midpoint.

L127 (fig. 3-96) until the vfo output is 5,500 1 kHz.

(3) Return the test fixture POWER ON-OFF

(17) Repeat steps (16) and (17) until both

switch to ON and adjust ERROR A ADJ and ERROR B

frequency settings are within the 1 kHz limit specified.

ADJ controls to provide 1.0 0.05 volt dc at test points

J19 and J20. Record the voltage at each of these test

(18) On the indexing fixture, set the switch to 5

points.

and rotate the slug rack control to 000. Adjust inductor

L138 (fig. 3-96) until the vfo output is 5,500 1 kHz.

(4) Again place the test fixture POWER ON-

OFF switch to OFF and install the module in the test

(19) Rotate the slug rack control on the

fixture.

indexing fixture to the 999 position and adjust inductor

L128 (fig. 3-105) until the vfo output is 6,500 1 kHz.

(5) With the multimeter connected to J19,

close the test fixture POWER ON-OFF switch to ON

(20) Repeat steps (18) and (19) until both

and note that the ERROR B LEVEL does not change

frequency settings are within the 1 kHz km specified.

more than 0.1 volt from the reading recorded in step

(21) On the indexing fixture, set the switch to

(3).

and rotate the slug rack control to 000. Adjust inductor

(6) Move the multimeter to J20 and observe

L139 (fig. 3-96) until the vfo output is 6,500 1 kHz.

that ERROR A LEVEL does not change more than 0.1

(22) Rotate the slug rack control on the

volt from the reading recorded in step (31.

indexing fixture to the 999 position and adjust inductor

(7) Adjust the receiver to 2.500 MHz and

L129 (fig. 3-105) until the vfo output is 7,600 1 kHz.

loosely couple the receiver antenna to the VFO jack on

(23) Repeat steps (21) and (22) until both

the test fixture.

(The frequency counter may be

frequency settings are within the 1 kHz limit specified.

connected to the test fixture VFO jack as an alternate

(24) On the indexing fixture, set the switch to 7

method.)

and rotate the slug rack control to 000. Adjust inductor

(8) On the indexing fixture (fig. 6-7), set the

L140 (fig. 3-96) until the vfo output is 7,500 1 kHz.

switch to 2, and rotate the slug rack control to 000

(25) Rotate the slug rack control on the

position.

indexing fixture to the 999 position and adjust inductor

(9) Adjust inductor L135 (fig. 3-105) until the

L130 (fig. 3-105) until the vfo output is 8,600 1 kHz.

vfo output is 2,500 1 kHz.

(26) Repeat steps (24) and (25) until both

(10) Rotate the slug rack control on the

frequency settings are within the 1 kHz limit specified.

indexing fixture to the 999 position and adjust inductor

(27) On the indexing fixture, set the switch to 8

L125 (fig. 3-96) until the vfo output is 3,500 1 kHz.

and rotate the slug rack control to 000. Adjust inductor

(11) Repeat steps (9) and (10) until both

L141 (fig. 3-96) until the vfo output is 8,500 1 kHz.

frequency settings are within the 1 kHz limit specified.

(28) Rotate the slug rack control on the

(12) On the indexing fixture, set the switch to 3

indexing fixture to the 999 position and adjust inductor

and rotate the slug rack control to 000. Adjust inductor

L131 (fig. 3-105) until the vfo output is 9,500 1 kHz.

L136 (fig. 3-105) until the vfo output is 3,500 1 kHz.

(29) Repeat steps (27) and (28) until both

(13) Rotate the slug rack control on the

frequency settings are within the 1 kHz limit specified.

indexing fixture to the 999 position and adjust inductor

(30) On the indexing fixture, set the switch to 9

L126 (fig. 3-96) until the vfo output is 4,500 1 kHz

and rotate the slug rack control to 000.

Adjust

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