Operation - TM-11-5820-554-120047

TM 11-5820-554-12

mating-type connector, use the adapter furnished, and

93 is set to the proper position before

ground the green wire. It is desirable to make a ground

plugging in the a.c. source. It is fused for

connection to the PP-3990/FRC-93KWM-2/2A

4-ampere primary current on 110-volt a.c.

combination, and the three-wire a.c. cord offers the

and for 2-ampere primary current on 220-

most convenient arrangement.

volt a.c. If the switch is set to the 110-

g. Set the Collins KWM-2/2A MIC GAIN control

volt position and the power supply is

fully counterclockwise until the switch clicks. Set the

operated from a 220-volt a.c. source,

OFF-ON-NB-CAL switch to ON. Set the meter switch

damaging high voltages may be developed

to PLATE and the EMISSION switch to LOCK. The

before the fuse blows.

transceiver is in receive condition during warm-up, so

a. Do not operate the power supply and transceiver

the meter will read full scale until the filaments reach

inside the carrying case with the cover closed. Be sure

operating temperature. This is normal S-meter action.

adequate ventilation is provided for the heat generating

When the S-meter falls back to zero, the circuits will

components of the equipment. The output is adequate

have switched to transmit condition and the meter will

for maximum KWM-2/2A ratings in LOCK key under

indicate plate current at approximately 40 ma. If plate

intermittent conditions. DO NOT operate in LOCK

current is other than 40 ma, adjust BIAS ADJUST

key or TUNE position under continuous key down

potentiometer R8 at the rear (fuse side) of the PP-

conditions.

3990/FRC-93 to set plate current to 40 ma. This

b. No other operating procedures are required.

setting is the proper idling current value for the Collins

Operation of the power supply is controlled from the

KWM-2/2A power amplifier tubes for linear operation.

switches and relays in the Collins KWM-2/2A.

The PP-3990/FRC-93-KWM-2/2A is now ready for

7-6.

Operator's

and

Organizational

use.

Maintenance

7-5. Operation

Operator's maintenance instructions are covered in

CAUTION

paragraph 7-26 and 7-27. Organizational maintenance

Be certain the 110/220 LINE VOLT

instructions are covered in paragraph

SELECTOR SWITCH on the PP-

7-28 and 7-29.

3990/FRC

Figure 7-4. Phone jack assembly during assembly.

7-4