Bill Cole, I need help

redbird · Post by **redbird** » Fri May 19, 2006 9:55 am

I have 2 BTL-301's with the same problem. There is no squelch. There is noise leaving the squelch control. I have not traced it any farther. I can not find my service manual for BTL301. Is the circuit like the BTH201? What parts cause the most trouble?

redbird · Post by **redbird** » Mon May 22, 2006 3:46 pm

I found the service manual. I have not found the problem. Receive sensitivity is good; however, noise with no signal is low at TP A. I verified this with another good radio. It is about 1/2 level of good radio. TP A is output of IF detector chip. I have changed IF chip, noise rectifier transistor, ceramic filter, and electrolytic capacitor in circuit. Last time I had a problem like this with a Maxar, it was leakage in the circuit board. I am running out of ideas.

redbird · Post by **redbird** » Wed May 24, 2006 5:31 pm

Problem repaired with Bill's help. IF coil and mixer coil must be peaked very carefully. When they are correct, background noise is at max and noise operated squelch will work good.