So I have an older cobra 29 that has no transmit or receive. The rx/tx light changes when I key the mic. The PA works so the audio chip seems to be good. All I hear is a click in the speaker when key up. The meter does not move on rx or tx. I replaced all the caps in the entire radio after checking several with a meter and they were way off, so I changed all the electrolytic caps. No change at all. I have checked voltage of almost every transistor in the radio. One question, on the final, one pin is ground, one pin is 12 volt and what should the 3rd pin read when keyed up? This reads 0 volts. I know that wouldn’t effect the receive if there was a problem on the transmit at that point. I can’t think of what component would effect both but the light still changes. I’m at a total loss. I’m a fairly capable hobbies, not a “tech”. Any help would be appreciated greatly
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Cobra 29 no rx or tx Help please!
- Thread starter mPoster
- Start date
Ok, not sure how big I now have receive. Like I said, I’m just a hobbyist… I have the receive aligned but it seems a bit off. Doesn’t have any static when no signal is being injected and it struggles with weak signal compared to other cobras I’ve done. Still nothing on the transmit side
Well, there is a lot out here for the Cobra 29,
There's a lot of things that are great about the radio, the main one being it's the Go-To for many people to use.
But it is also one being the most popular, has also the most documentation on various problems with the radio and many solutions on how to fix them.
So, to help you get started - you need some form of a "tune up" guide for your radio.
Unfortunately, the Cobra 29 has undergone several revisions - and changes along the way, so much of what we can provide will only go so far for it's meant more for the OLDER radios than the newer Cobra 29's.
To help, and this would provide a lot of reading, but it might get you up to speed to help know what needs to be done to fix that radio...
One time - long ago, we used to offer - Hey, go here to this site and it has everything you need to know how to get your radio to work...
Now, we don't we (the internet) lost the site to a pay-to-access firewall run by a person that is not the original owner of the data - so in a way it was hijacked and taken away - at least nothing is set up to replace it just yet.
So, All I can provide in our place here, at THIS (our site WWDX) for you to maybe glean enough information on what needs to be done...
Use these threads
https://www.worldwidedx.com/threads/need-help-with-side-mic-cobra-29-ltd-classic.251271/#post-702194
https://www.worldwidedx.com/threads...e-until-it-warms-up.239208/page-2#post-659728
https://www.worldwidedx.com/threads/cobra-29-nw-problem.259823/#post-740762
www.worldwidedx.com
www.worldwidedx.com
www.worldwidedx.com
www.worldwidedx.com
www.worldwidedx.com
www.worldwidedx.com
www.worldwidedx.com
The best I can do at the moment for you...
There's a lot of things that are great about the radio, the main one being it's the Go-To for many people to use.
But it is also one being the most popular, has also the most documentation on various problems with the radio and many solutions on how to fix them.
So, to help you get started - you need some form of a "tune up" guide for your radio.
Unfortunately, the Cobra 29 has undergone several revisions - and changes along the way, so much of what we can provide will only go so far for it's meant more for the OLDER radios than the newer Cobra 29's.
To help, and this would provide a lot of reading, but it might get you up to speed to help know what needs to be done to fix that radio...
One time - long ago, we used to offer - Hey, go here to this site and it has everything you need to know how to get your radio to work...
Now, we don't we (the internet) lost the site to a pay-to-access firewall run by a person that is not the original owner of the data - so in a way it was hijacked and taken away - at least nothing is set up to replace it just yet.
So, All I can provide in our place here, at THIS (our site WWDX) for you to maybe glean enough information on what needs to be done...
Use these threads
https://www.worldwidedx.com/threads/need-help-with-side-mic-cobra-29-ltd-classic.251271/#post-702194
https://www.worldwidedx.com/threads...e-until-it-warms-up.239208/page-2#post-659728
https://www.worldwidedx.com/threads/cobra-29-nw-problem.259823/#post-740762
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