Symptom

Probable Cause

Remedy

Unit does not work at all

1.Defective power switch VR102

2. Blown fuse

3. Broken DC power cord

4. Defective IC101 or IC 102

1. Replace

2. Replace

3. Replace

4. Replace

No output from speaker at all

1. Defective external speaker jack

2. Poor connection on microphone connector

3. Defective push switch on microphone

4. Defective internal speaker

5. Defective D105, VR101, VR102, RV103 IC103 or other components

1. Repair or Replace

2. Repair or Replace

3. Repair or Replace

4. Replace

5. Replace the defective components

No noise on speaker

1. Measure all the voltage of Q101, Q102, Q103, Q104, Q105, Q106, Q107, Q108, Q109, and IC103 with voltage chart

2. Defective squelch circuit components(RV1O3, VR1O1, IC103, Q202, Q204, Q205, Q210, Q211)

1. Replace

2. Replace

Squelch does not work

1. Defective VR101, RV103, Q202, Q204, Q205, Q210, Q211

2. Improperly adjusted RV1O3

1. Replace defective components

2. Readjust

No modulation

1. Defective microphone

2. Poor Audio output and defective modulation microphone amplifier components(Q201, Q203, IC103, VR101)

3. Defective microphone connector component

4. Defective ALC Circuit (Q308, Q309, Q310, D203, D204)

1. Replace

2. Replace the defective component(s)

3. Replace

4. Replace the defective component(s)

LED meter does not work

1. Defective D303, D304, D305, D306

2. Defective IC104

3. Defective D106, D111, RV101, RV1O2

1. Replace

2. Replace

3. Replace

LED Display does not work

1. Defective orange wire fuse

2. Defective LED501, IC101, IC102

1. Replace

2. Replace

P.A does not work

1. Defective VR102, SW2

2. Defective Q201, Q202, Q203, Q204, Q205, Q213, D209, IC101, IC102

1. Replace

2. Replace

Channel selector does not work

Defective IC101, SW5, SW6, SW7, SW8

Replace

ANL does not work

1. Defective SW3

2. Defective Q109

1. Replace

2. Replace

CH9 does not work

1. Defective SW4

2. Defective D216, Q213,IC101, IC102

1. Replace

2. Replace