Listening Test; Functional Tests; Test Setup - Shure U1 Service Manual

Shure U1/U1L Body-Pack 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.

Test Setup

1. Use a U4 receiver for the following functional tests.
2. Dc voltages are present at most rf test points. Use dc blocks
to protect the test equipment, if necessary.
3. Connect the (+) power supply terminal through a milliammeter
to the (+) contact on the battery nest, and the (–) power supply
terminal to (–) the contact on the battery nest.
4. Connect a dc voltmeter across the power supply and set the
power supply for +3 Vdc..
5. Connect the audio generator to the mic-jack board either via the
TINI QG connector, or the LEMO connector to BNC cable,
depending on mic style.
Rf Power
1. Attach a U4 antenna to the spectrum analyzer.
2. Turn the U1 on and hold it very close to the antenna. Move the
U1 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. Verify that the current drain is less than 110 mA.
6
25C1021 (BG)