5: Maintenance
PRC-PS-MS
5-5
DC Input
Circuitry Check
1. Disconnect the AC input power source and connect the DC input power
source.
2. Adjust the DC supply voltage to between 20 Vdc and 30 Vdc.
3. Verify that the charger is working normally by performing the previous
checks (exclude the reverse-current protection check) on the
INTERNAL charging station.
Chassis Over-
Temperature
Protection
1. Remove the PRC-PS chassis from the case (
2. Use a heat source such as a heat gun or blow torch to heat the thermostat
until it trips.
3. Verify that the PRC-PS shuts off until the thermostat trips back on.
Audio Circuit
Check
1. Use an AC voltmeter to monitor the AC voltage across the speaker (pins
P and A on the SET POWER connector).
2. Turn the front panel AUDIO GAIN control to the SPKR OFF position.
3. Adjust the 1 kHz audio source for 0.5 Vpp and apply the audio signal to
pins A and P on the SET POWER connector (J1).
4. Slowly turn the AUDIO GAIN control clockwise until the AC voltmeter
reads 2.8 Vrms. Listen for excessive audible distortion.
5. Adjust the AUDIO GAIN control to a normal listening level. Ground pin
C (PTT) on the SET POWER connector and verify the speaker audio
shuts off.
6. Remove the ground from pin C and verify the speaker audio comes back
on.
This concludes the functional test. If the PRC-PS failed any of the previous
steps,
