Shure U4D Service Manual page 25

Second Mixer Coil Alignment (Channel A)
RF SIGNAL GENERATOR
DC BLOCK
DC VOLTMETER
25D1062 (AG)
Shure U4D Dual Diversity UHF Receiver
NOTE: DC VOLTAGES ARE PRESENT
AT MOST RF TEST POINTS. USE A DC
BLOCK ON THE RF SIGNAL GENERATOR
TO PROTECT TEST EQUIPMENT.
ANTENNA A IN
S201
(OFF)
P202
P203
U303 / U315
PIN 8 / PIN 17
L313
J302
Figure 8. Channel A Second Mixer Coil Alignment
1. Change the rf input level to –105 dBm.
2. Adjust L313 for maximum dc voltage at U303 pin 8 for PCB ver-
sion 34A8507 or at U315 pin 17 for PCB version 34A8703.
24
S201
(OFF)
P202
P203
Service Procedures
ANTENNA B IN
P202
P202