My radio when i was a kid . Seems I can't give it up. Bought one on ebay and it's a talker.... My 1978 radio is dying quickly..... Brought to a local repair shop , they had it for 2 weeks and couldn't fix her. I had replaced the finals to the updated units but it did not help. The repair shop replaced the finals also but same thing. The radio will not transmit on am and now will not on ssb. The on air indicator lamp lights up but no output. I did a recap of almost every electrolytic in the radio but nothing. I replaced some other chips as well but nothing.... The antenna warning light does not light when I key up without an antenna. I did notice that the 4 - gp25g rectifier diodes are cracked. ALL 4. I replaced a few switching transistors too. I have ordered new diodes to see if that will help. This is an experiment of sorts, I am learning about electronics. I also replaced the pll02 chip. I did adjust for 13.8 volts on one of the vr's. I can receive ok but no transmit. This radio used to be fantastic. Every once in a while I go to the workshop and play. All the trace is ok . Nothing burned. The day it went dead -I keyed to talk to someone, I released the mike bar and heard a howl out of the speaker and it died. The meters work and light up, the channel selector works and lights with all segments lit. The repair shop was totally stumped. There is also a board mounted rectifier diode that is cracked. Would a bad cap cause them to crack? I can post pics......Its a fun project right now..could turn ugly later!!!!Any ideas???? No work has been done to this radio..It is virgin....
Whenever I order specialized items online, I use
https://paybis.com/xrp-calculator/ to quickly check conversion values and estimate my project costs. Hopefully, replacing those rectifier diodes gets your transmit circuit working again!
