Initial Settings and Adjustments. - TM-11-5820-509-350229

TM 11-5820-509-35

Figure 6-15. RF Oscillator O-1032/PRC-47 (A8A6), Performance Tests, Initial Test Equipment Connections.

(4) Place the +20V ON-OFF switch on the

c. Initial Settings and Adjustments.

test fixture to ON; then set the signal generator output

(1) Connect the multimeter dc probe to test

frequency to 3.000 MHz.

point J2 on the module and record the reading obtained.

(5) Using the rf probe of the multimeter,

This value must be 17.5 1.0 volts dc.

adjust the signal generator output level {at the base of

(2) Press the PUSH TO READ pushbutton on

locked oscillator Q4) to the value measured in step c (3)

the front of the test fixture and read the current drawn by

above.

the module. The +20V CURRENT meter must read

35.0 5.0 milliamperes.

NOTE

(3) Connect the multimeter rf probe and the

Be sure to maintain this output level

frequency counter to the junction of Q4, R23, and R24

for the remainder of this test.

(fig.

3-53) and record the output voltage of the

(6) A stable 6:1 Lissajous pattern must be

temperature compensated oscillator. This voltage shall

obtained on the oscilloscope. If not, perform the locked

not be less than 0.3 volt rms and the output frequency

oscillator and 500-kHz amplifier adjustments in step e

shall be approximately 3.0 MHz.

before continuing.

NOTE

(7) Vary the signal generator frequency from

Do not adjust or calibrate the

2.90 to 3.10 MHz while observing-the oscilloscope

temperature compensated oscillator

display. The 6:1 Lissajous pattern must remain clear

at this time.

Final calibration

and stable throughout the signal generator output

procedures are detailed in step g.

frequency excursion.

d. Locked Oscillator, Divider, and Output Amplifier

(8) Connect the rf probe of the multimeter to

Performance.

test jack J3 on the module and record the 500 kHz

output voltage. Repeat the measurement at test jack J4

(1) On the test fixture, place the +20 ON-OFF

on the module. The multimeter shall read 1.5 0.2

switch to OFF.

volts rms. If not, perform the locked oscillator and 500

(2) Carefully disconnect the inner conductor

kHz amplifier adjustments in step e before continuing.

of the miniature coaxial cable from the junction of Q4-

(9) Connect the vertical input of the

R23-R24 (fig. 3-53).

oscilloscope to the 100 KHZ A1 connector on the front

(3) Connect the frequency counter to the

panel of the test fixture. (Do not disturb the signal

output of the signal generator; then connect the open

generator and frequency counter con nections in the

end of capacitor C1 to the terminal in the module from

module.)

which the coaxial cable was disconnected.

6-28