General Adjustment Procedures

11-6625-467-34

d. RF amplifier/detector gain and frequency

(5) Lift up the connector plate (5) approxi-

response adjustment (para 3-21).

mately 3/4 inch and remove the connector.

e. 150 Hz oscillator/counter adjustment (para

NOTE

3-22).

The tips on the card guides (14 and 15) fit

f. 1-kHz oscillator adjustment (para 3-23).

i n t o the receptacle connectors (4). Lift

g. 500-kHz fm oscillator frequency adjustment

straight up on connectors when removing

(para 3-24).

then..

h. 500-kHz fm oscillator deviation sensitivity ad-

justment (para 3-25).

b. Replacement.

i. 3.975 MHz oscillator detector output amplitude

(1) Connect any jumper wires that are required

adjustment (para 3-26).

on the connector plate (3).

j. 5.925 MHz oscillator detector output amplitude

(2) Lift up the connector plate approximately

inch and place the receptacle connector (4) on the

adjustment (para 3-27).

k. 5 0 0 - k H z b a n d p a s s f i l t e r a d j u s t m e n t ( p a r a

card guide (14 and 15) tips.

3-28).

(3) Replace the 15 machine screws (12) and the

l. 500-kHz discriminator adjustment (para 3-29).

15 lockwashers (13) in the connector plate (3).

m. Spiking circuit duty cycle adjustment (para

(4) Solder the wires to the terminals on the

3-30).

connector plate (3).

n. Despike detector adjustment (para 3-31).

(5) Replace the keys in the new connector. The

o. 30-MHz oscillator tuning adjustment (para

chart below (table 3-4) shows the keying code for

3-32).

each circuit card connector.

p. 68-MHz oscillator tuning adjustment (para

3-17. General Adjustment Procedures

3-33).

q. RF power detector adjustment (para 3-34).

Paragraphs 3-18 through 3-34 describe adjustment

procedures for the various functional circuits in the

t e s t set. Always perform the adjustment pro-

3-18. +28-Volt Regulator Adjustment

cedures for a circuit after a repair operation. The

Perform the following procedures to adjust the

adjustment procedures can also be used in trouble-

+28-volt regulator:

shooting the test set by attempting to adjust a cir-

a. Remove the test set from the case.

cuit that is suspected to be faulty. If the circuit can-

b. Using the module extender board, extend

not be adjusted, the fault is probably in that circuit.

+28-volt regulator circuit card HU4 above the card

When a complete alignment of the test set is neces-

cage.

s a r y , perform the adjustment procedures in the

c. Connect power to the equipment and set the

o r d e r of their appearance. The adjustment pro-

POWER switch to ON.

cedures and paragraph references are listed in a

d. Pull the shaft of interlock switch S12 to the

through q below.

a. +28-volt regulator adjustment (para 3-18).

override position.

e. S e t t h e P O W E R S E L E C T O R s w i t c h t o

b. 28-volt regulator adjustment (para 3-19).

NORMAL.

c. Audio amplifier/detector gain adjustment

f. Connect the ME-202/U between J3 (+) and J5

TABLE 3-4, Circuit Card Connector Keying Code

3-43