Service manual

Shure LX2 Hand-Held Transmitter

Service Procedures

25D1006 (CG)

Power and Display Check

LX2 Transmitter

Power supply: 9 Vdc

Power switch: PWR

Mic switch: MUTE

Gain: Mid

Figure 9. Power and Display Check Test Set-Up

1. Make sure the power OFF/PWR switch is in the PWR position.

2. With the 9.0 Vdc power supply connected, the green LED should

be illuminated.

3. Reduce the power supply to 6.6 Vdc. The yellow battery LED

should be illuminated.

4. Reduce the power supply to 6.0 Vdc. The red battery LED

should be illuminated.

5. Return the power supply to 9.0 Vdc.

6. Make sure the mic ON/MUTE switch is in the MUTE position.

7. Connect the positive (+) lead of a 9.0 Vdc power supply to the

positive battery terminal on the audio board. Connect the nega-

tive (–) lead to the battery terminal (audio board ground). The

green power LED should now be illuminated. If not, there is a

circuit malfunction.

8. Temporarily reverse the polarity of the 9.0 Vdc power supply.

The green power LED should be extinguished, and no current

should be drawn from the supply. Otherwise, there is a problem

with the reverse polarity protection circuit. Return the polarity of

the 9.0 Vdc power supply to normal.