Cobra 2000 GTL Issue

[Raccoon]

Hi everyone, I've got a 5 pin Cobra 2000 GTL that I'm having an issue with . I haven't used it in awhile , so I pulled it out , and wired my D104 Silver Eagle up to it ... and first of all, it's receiving whether I have the mic hooked up to it or not . And second , in order to hear the CB , I have to have the "PA/CB" switch in the "PA" position . If I switch it to the "CB" position , it acts like it's in the "PA" position ... nothing is heard . Remember , this is a 5 pin , I shouldn't be hearing anything without my mic plugged into it .

So does anyone know what's going on with this radio ? It's never done this before , it worked fine the last time I used it .

 

[Raccoon]

I think I may have answered my own question .

I've been researching , and I think that the VR12 may be the culprit. Previously my Cobra 2000 was having a mic gain issue . If you turned the mic gain up to around the 10 or 11 o'clock position it would get really wonky when it was keyed up . Now there's no transmit and it has to be in the PA position to receive . I've found a few others that had this same problem ... and they fixed it by replacing VR12 . I just thought you might like an update.

 

[357]

you may be plugged into the pa jack not the speaker jack

 

[Raccoon]

you may be plugged into the pa jack not the speaker jack

No, I made sure that I was plugged into the external speaker jack ... lol

 

[357]

has someone replaced the socket to 4 pin?
maybe someone jumped a couple pins on the mic pcb under the radio. should be deaf with no mic

 

[Raccoon]

has someone replaced the socket to 4 pin?
maybe someone jumped a couple pins on the mic pcb under the radio. should be deaf with no mic

No, it's still a 5 pin mic jack. It used to be my grandmothers , and I inherited it a few years ago when she passed away. So I know it's history . She bought it new , and never had any crazy work done to it . It worked really well for the first year or so. But then recently it started acting up. I'm just trying to get it figured out so I can get it back up and running .

 

[nomadradio]

Hmm. Long shot:

Lightning hit a nearby utility pole while the antenna coax was connected. Fried one of the disc capacitors connected to the receive circuit coming from pin 3 on the mike socket.

Yeah, out there. But a surge-shorted disc cap with one side grounded can do squirrelly things.

73

 

[Raccoon]

Hmm. Long shot:

Lightning hit a nearby utility pole while the antenna coax was connected. Fried one of the disc capacitors connected to the receive circuit coming from pin 3 on the mike socket.

Yeah, out there. But a surge-shorted disc cap with one side grounded can do squirrelly things.

73

Actually, no . I disconnected it, and stored it away for a year or two. It was fine when I disconnected it and put it away. Then when I pulled it back out and hooked it up again a few years later, it's doing this craziness instead of acting the right way now.

 

[Old_Crow]

Might be a Cap or a few caps shorting out! Was it ever recapped?

 

[Raccoon]

Might be a Cap or a few caps shorting out! Was it ever recapped?

No, it's never been recapped before. Everything is still original in it. But I did get a recap kit for it from Klondike Mike. So that will be getting done.

 

[nomadradio]

I would check for a resistance reading from each pin of the tube socket going to the chassis. Just sounds like a fault in that department.

Maybe. Should be no DC continuity from any of the five mike-socket pins and the chassis. An analog meter may show a brief "kick" of the needle but no steady resistance reading at all.

73