The Defpom Forum, for RadioMods, S&M Software and Music by The Defpom

I have a Galaxy 44v main board #360014b that when you key the radio up it wants to squeal even with the talk back turned off. I noticed that if i remove the top cover on the radio it stops squealing and soon as i replace cover it starts squealing again. Could something be leaking RF's inside the radio causing this. I also noticed that if i turn the RF power up to about a 4 watt carrier it will stop squealing Not sure where to start. Also forgot to mention that it doesnt matter how i adjust the mic gain it still squeals. Thanks

Jack,
Check the choke on the Mic jack board also check the insulator plates on the Driver and Final they must be ceramic insulator types.

Thanks for the reply Rick i have checked the chokes and the insulators are the ceramic type. Also i noticed that when i have the radio keyed i can turn the volume knob and the squeal will go from like a faint mic squeal with the volume turned up to a bad feed back squeal with the volume turned all the way down. As i said in the first post it also goes away when i change the carrier from 1 watt to 4 watts i have also tried different mics with no luck . Thank you for your time.

It sounds like the audio chip (IC8) is not going in mute in the TX mode. Check pin 5 in TX it should be about 5 to 6 volts, you can check if this is the fault by soldering a 10K resistor from pin 5 to the collector of TR38, if the problem go away then check TR39 and D80. I have come across D80 o/c quit a few times.

Thanks for your help Rick when i checked the insulators on the final the first time i just glanced at them to confirm they were the ceramic type but upon closer inspection of them found that it was cracked and seperated a little so i replaced it and every thing is fine now. Thanks again