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Hello all, its been a while since i got the cobra 2000 working with your help, and its been fine ever since. Recently i noticed a slight crackle on the Audio so i opened it up to have a look around. I was checking out the wiring and noticed a brown wire had come adrift . I have taken a...

Be safe folks..

Well it was a great journey , Andy is right of course it's all about people. Helping sharing, just as is going on around the world right now.

Thank you., I had great doubts at the start, but you guys have great encouragement, that led to a successful result..

Good morning, So the radio is fixed, thanks to all your help. I just copied a contact in Germany. So I started to check out the alc circuit, checked out the diodes around including a50 and a50 they were ok. Checked out the wiring to the cb...pa switch all good. The pot 11 was also ok Then looked...

thanks Andy, son far so good the radio is still working this is the longest it has operated since we began the adventure. THe power is back up and the audio is fine. I think it will live again. So tr24 is checking out ok so something associated with its circuit could be the problem. I think you...

Good evening, well Andy all i will say is your a genius and thank you for sharing your knowledge. I think the way you explain things is magic. For me i remember my father in the early 1960s , he used to trick around in the old valve radios, i used to be fascinated watching him. He never...

just got back to the radio and its not working, unusual as it usually works from cold. I think theres a problem with the 7.8. Signal from tr32 When i left the radio earlier the 7.8Mhz was at tp3 strong. However now it is not at tp3. There is a small.25v signal at pin3 an612 7.8Mhz...

Hi Leo, well I think the guys on here are amazing. They put so much of there time into these repairs. This cobra is doing strange things today..with r21 out. And it has died again just now, but there is now a good 7.8 Mhz on tp3.... For me it's an education in these posts on here. Wonderful...

hello there, ok so today i have removed tr21 and am operating the radio without it on ssb. i has not gone off yet but i will try it after for a while and see how...if... it goes. i have been tracing the yellow cable. also there is a .5v signal of 7.8 at pin 3 of the an612. the radio is...

Thanks Robalo that's good so. As it's raining today I get to do another bit on the radio. So I have changed tr21, I dont see any improvement. Also I have checked pin 7 of the an612 It has 7.8Mhz during am transmit. I can't see 7.8 on the Tp 3. What should I be getting at the tp3. , when I touch...

Today i have checked out the bias currents for predriver and driver. they were slightly high driver 67 and predrive 33 Ma. SO i set these to 60Ma and 30Ma.. I have looked at the resistors R 131 Its there intact and reads ok R 125 It reads correct also R 123. I wonder should i change...

Thank you for clearing up the an612 role. All the electronic capacitors are renewed. The last repair was the replacement of tr 20. Nothing else changed. I will check out the an612 and change tr21. Nothing is heating up, as far as I can see. Should I try an electronic capacitor in place of c193...

Thanks Mike, I'll give it a try. Is the an612 used for the am modulation also or just the ssb

Thanks Andy. I will check out things heating up, Where I have the scope on the base of tr23 when the tx stops on USB, no audio signal appears on the scope. if i switch to am the Mike audio is there. The collector voltage of tr 23 is a bit low and the base volt is 1.7, a bit high according...

Hi, SO the radio has been working fine since the last repair Now i notice that after a few minutes of ssb use the tx audio dies away. THe tx indicator switches on ok but no rf going out, if i switch back to am the signal and modulation are fine. If i switch off the radio for a while the ssb tx...

Good afternoon all, so the radio is fixed, Came back yesterday after our walk refreshed !!! SO this morning had a look at all the posts and decided to have a another look I did a check on the back of the board for shorts and or broken tracks ...nothing all good. So back to in 17 and...

Well we are now back home we have walked the tain BO Chuailge way across ireland 500k.....wonderful

Fascinating I really admire your determination..all of you..