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Shure U4D Dual Diversity UHF Receiver
12
25D1062 (AG)
Preliminary Tests
8. Make sure the tone key switch (S201) on the receiver rf-audio
board is in the ON position.The receiver should be muted. No
audio output should be present at the balanced and unbalanced
outputs.
9. Slide the tone key switch to the OFF position. J211 can be
accessed from the outside of the receiver and is marked
BALANCED LOW Z. With the audio analyzer in the Float
position, the audio voltage at balanced audio output J211 with
the switch at the LINE position (pin 2 and 3, unloaded) should
be as follows:
UA, UB MA, MB, MC, MD:
2.5
±
0.5 Vrms
KK: Not available at this time;
measurements will be available later.
II:
1.7
±
0.5 Vrms
10. J209 can be accessed from the outside of the receiver and is
marked HIGH Z. With the audio analyzer NOT in the Float
position, the audio voltage at unbalanced audio output J209
(pin 1 and 2, unloaded) should be as follows:
UA, UB,MA, MB, MC, MD:
1.25
±
0.25 Vrms
KK: Not available at this time;
measurements will be available later.
II:
0.837
±
0.25 Vrms
11. Set the rf signal generator Level to –105 dBm. The receiver
should be muted. No audio output should be present.
12. Connect a dc voltmeter to the center conductor (+) and the
ground (–) of receiver BNC antenna channel B input, marked
ANTENNA B IN. The measured voltage should be 12.0
±
0.5 Vdc.
13. Set the rf signal generator Level to –90 dBm, and connect it to
the receiver BNC antenna channel B input, marked ANTENNA
B IN. Be sure to use a dc block to protect the test equipment.
14. Repeat steps 7 through 11.
15. Return the tone key switch (S201) to the ON position.
16. Repeat the procedure on the second receiver.
Summary of Contents for U4D
Page 11: ...Shure U4D Dual Diversity UHF Receiver 10 25D1062 AG Preliminary Tests Audio Rf Board Side 2...
Page 46: ...Shure U4 UHF Diversity Receiver 25D1062 TL 45 U4 Rf Audio Printed Circuit Board Legend Side 1...
Page 47: ...Shure U4 Diversity UHF Receiver 46 25D1062 TL U4 Rf Audio Printed Circuit Board Legend Side 2...