Shure U4D Service Manual page 33

Audio Level Setup, Channel A
RF SIGNAL GENERATOR
AUDIO ANALYZER
NOTE: DC VOLTAGES ARE PRESENT
AT MOST RF TEST POINTS. USE A DC
BLOCK ON THE RF SIGNAL GENERATOR
TO PROTECT TEST EQUIPMENT.
For the following test, make sure the tone key switch (S201) is OFF.
25D1062 (AG)
Shure U4D Dual Diversity UHF Receiver
ANTENNA A IN
S201
(OFF)
DC BLOCK
U207
P203
J302
Figure 16. Channel A Audio Level Setup Connections
All Models (Except II and KK Models)
1. Set the rf signal generator deviation to 45 kHz and modulating
frequency to 1 kHz.
2. Connect the rf signal generator to BNC connector ANTENNA A
IN on the receiver back panel.
3. Place the (+) terminal of the audio analyzer on U207, pin 7, and
connect the (–) terminal to ground.
4. Adjust R203 until the audio analyzer reads 0.436 ± 0.005 Vrms.
5. Disconnect the rf signal generator from the BNC connector
ANTENNA A IN on the receiver back panel.
II Models (Japan)
1. Set the rf signal generator deviation to 28 kHz and modulating
frequency to 1 kHz.
2. Connect the rf signal generator to BNC connector ANTENNA A
IN on the receiver back panel.
3. Place the (+) terminal of the audio analyzer on U207, pin 7, and
connect the (–) terminal to ground.
4. Adjust R203 until the audio analyzer reads 0.282 ±. 003 V.
5. Disconnect the rf signal generator from the BNC connector
ANTENNA A IN on the receiver back panel.
KK Models (United Kingdom)
1. Set the rf signal generator's deviation to 40.0 kHz and modulat-
ing frequency to 1 kHz.
2. Connect the rf signal generator to BNC connector ANTENNA A
IN on the receiver back panel.
3. Place the (+) terminal of the audio analyzer on U207, pin 7, and
connect the (–) terminal to ground.
4. Adjust R203 until the audio analyzer reads 0.436 ±. 003 V.
5. Disconnect the rf signal generator from the BNC connector
ANTENNA A IN on the receiver back panel.
32
S201
(OFF)
R203
PIN 7
P203
P202
P202
Service Procedures
ANTENNA B IN
P202
P202