Listening Test; Functional Tests; Current Drain - Shure U2 Service Manual

Shure U2 Hand-Held UHF Transmitter

Listening Test

Functional Tests

Preliminary Tests
Before completely disassembling the transmitter, operate it to deter-
mine whether it is functioning normally and try to duplicate the reported
malfunction. Refer to the User Guide for operating instructions, trouble-
shooting, and specifications.
Review any customer complaint or request, and focus the listening
test on any reported problem. The following, more extensive, functional
tests require partial disassembly.
Refer to the Disassembly section to partially disassemble the
transmitter for the following functional tests.
Use dc blocks at all rf outputs to protect test equipment.
Use a U4 receiver for the following functional tests.
Test Set-Up
1. Dc voltages are present at most rf test points. Use dc blocks
to protect the test equipment, if necessary.
2. Insert two fresh AA batteries into the U2 battery nest.
3. Connect the audio analyzer to the microphone via the
microphone test head.
Rf Power
1. Attach a U4 antenna to the spectrum analyzer.
2. Turn the U2 on and hold it very close to the antenna. Move the
U2 up and down to maximize power on the spectrum analyzer.
3. Verify that output power is greater than 3 dBm.

Current Drain

1. Apply 3.0 Vdc to the battery terminals.
2. Connect the amp meter between the positive (+) battery lead
and the positive (+) battery terminal of the U2 transmitter.
3. Verify that the current drain is less than 110 mA.
6
25B1022 (AG)