SB-023

Service notes on TR-7200A                             10-31-77


RECEIVER

1.   No squelch:  Check C84 47uf on X55-1110-11.

2.   Intermittant receive:  Check for D14 touching to ground on X55-1110-
11.

3.   Both Q17, Q18 audio transistors burned up:  Send for bulletin before
replacing.

4.   Poor receiver sensitivity:  Check for proper output of Q10 10.245 MHz
stage.  If it is defective replace xtal.

5.   No receiver audio noise:  Check L23 discriminator coil.

6.   No receiver:  No C9  voltage at X55-1110-11.

7.   Receiver sensitivity poor:  Check D2 MI301.


Transmitter

1.   Distortion on audio TX:  Bad Q8 TA7061 IC.

2.   No TX HI:  Check for shorting terminals at HI/Low switch.

3.   No TX:  Check for proper T9 voltage at X56-1190-11.

4.   No TX:  Collector voltage SB at X45-1080-00.  Check Q9 2SA496Y.

5.   No TX:  Check D1 MI301.




(c) 102177TKC