Manual

tance of the load or if you have reason to suspect a resistor

has failed, the following procedure may be helpful in finding

a faulty resistor.

1. Make a visual inspection of all the resistors.

Check for cracks or burned spots on the surface

of each resistor. If no visual discrepancies are

found to indicate resistor failure, it will be neces

sary to take resistance measurements on each re

sistor individually.

2. Use a digital multimeter or an ohmmeter with

an accuracy of 1% at 50 ohms. After removing

the resistor from its retaining clips connect the

test leads across each resistor end. The individ

ual resistance measurements at 25°C (77°F)

should be 480 ohms ±20%.

3. Record the value of the resistance. If resistors

are found that greatly exceed the respective

ranges, they should be replaced.

Replacing

Resistors

The resistors are held very firmly in their clips. Use caution

and carefully remove one end of the resistors at a time. Do

not use excessive force, as there is the possibility of the re-

sistors chipping or cracking.

Assembly

To reassemble the RF assembly and panels, reverse the dis-

assembly instructions given above. Be sure to install all of

the screws in the panels.

WARNING

Disconnect this unit from the RF power sources before

any disassembly for repair or replacement procedures.

The potential for electrical shock exists.

Replacing the

Thermoswitch

The thermalswitch is located on the backside of the internal

airflow deflector plate closest to the external interlock ter

minal.

1. Remove the 1-5/8 connector from the front panel.

Note: Be sure to remove the two small hex

screws holding the inside flange to the panel.

Remove the panel and detach the

thermalswitch wires from the front panel ter

minal

Maintenance