Rf Alignment, Receive Mode

TM 11-5820-509-35

inductor L142 (fig. 3-96) until the vfo output is 9,500 1

g. Rf Alignment, Receive Mode

kHz.

(1) On the test fixture, place the FUNCTION

(31) Rotate the slug rack control on the

SEL switch to RCVR, the LOOP SEL switch to

indexing fixture to the 999 position and adjust inductor

CLOSED, and then place the POWER ON-OFF switch

L132 (fig. 3-105) until the vfo output is 10,500 1 kHz.

to ON. Set OSC CONTROL to 0 and 09.

(32) Repeat steps (30) and (31) until both

(2) Rotate the switch on the indexing fixture

frequency settings are within the 1 kHz limit specified.

(fig. 6-7) to 2 and set the slug rack control to the 000

position.

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

10 and rotate the slug rack control to 000. Adjust

(3) Adjust the signal generator to 2.0 MHz,

inductor L143 (fig. 3-105) until the vfo output is 10,500

CW operation, and connect the RF OUTPUT jack to the

1 kHz.

RCVR ANT jack of the test fixture.

(34) Rotate the slug rack control on the

(4) Connect the voltmeter to the AUDIO OUT

indexing fixture to the 999 position and adjust inductor

jack of the test fixture and adjust the signal generator

L133 (fig. 3-96) until the vfo output is 11,500 1 kHz.

output frequency and level controls until an indication is

obtained on the voltmeter.

(35) Repeat steps (33) and (34) until both

frequency settings are within the 1 kHz limit specified.

(5) Adjust inductors L7, L22, L37, and L52

(fig. 3-105) to obtain maximum voltmeter reading.

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

Minimum limit is 0.04 volts rms.

11 and rotate the slug rack control to 000. Adjust

indictor L144 (fig. 3-105) until the vfo output is 11,500

NOTE

1 kHz.

Adjust the output level of the signal

(37) Rotate the slug rack control on the

generator and the voltmeter scale

indexing fixture to the 999 position and adjust inductor

multiplier as required to reduce the

L134 (fig. 3-96) until the vfo output is 12,500 1 kHz.

possibility of limiting within the

(38) Repeat steps (36) and (37) until both

several modules.

frequency settings are within the 1 kHz limit specified.

(6) Rotate the switch of the indexing fixture to

(39) Without further adjustment to the

3 and set the output of the signal generator to

inductors mentioned above, record the oscillator output

approximately 3.0 MHz. Adjust the output level and

frequencies for each setting of the band switch and the

frequency of the signal generator until an indication is

slug rack control on the indexing fixture. The maximum

obtained on the voltmeter.

allowable deviation from the desired oscillator output is

(7) Adjust inductors L8, L23, L38, and L53

12 kHz within any one band.

(fig. 3-105) to obtain maximum voltmeter reading.

Minimum limit is 0.04 volts rms.

NOTE

(8) Rotate the switch of the indexing fixture to

If the frequency deviates more than

4 and set the output of the signal generator to

this amount from the desired value,

approximately 4.0 MHz. Adjust the output level and

tracking correction is necessary. If

frequency of the signal generator until an indication is

the majority of the bands is high (or

obtained on the voltmeter.

low) at the 500 position of the slug

(9) Adjust inductors L9, L24, L39, and L54

rack control, adjust C344 (fig. 3-98).

(fig. 3-105) to obtain maximum voltmeter reading.

If C344 fails to compensate for

Minimum limit is 0.04 volts rms.

tracking error, replace one or more of

(10) Rotate the switch of the indexing fixture to

the capacitors (C299, C301, C303,

5 and set the output of the signal generator to

C305, C307, C309, C311, C313, C315

approximately 5.0 MHz. Adjust the output level and

or C317) in the shunt coil

frequency of the signal generator until an indication is

assemblies. The low frequency end

obtained on the voltmeter.

of bands 3 through 11 (M Hz) can be

(11) Adjust inductors L10, L25 L40, and L55

raised or lowered to a maximum

(fig. 3-96) to obtain maximum voltmeter reading.

deviation of 8 kHz to assist in

Minimum limit is 0.04 volts rms.

tracking at mid-band. Do not adjust

(12) Rotate the switch of the indexing fixture to

the low -frequency end of the 2.0 M

6 and set the output of the signal generator to

Hz band.

approximately 6.0 MHz. Adjust the output level and

frequency of the signal generator until an indication is

obtained on the voltmeter.

(13) Adjust inductors L11, L26, L41, and

6-22