Hi I'm new here and would like to do this mod to my Cobra 29 LTD Chrome AM/FM Cb. I can't find the jumper it is talking about in the photo.
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Need Help With Cobra 29 Mod
- Thread starter ChromeCobra
- Start date
I apologize, I can't make out the picture it's blurry.
NPC mod maybe?
Can you link to where you found the image?
73
Jeff
Here is the original post https://www.worldwidedx.com/threads/sweet-easy-variable-dead-key-for-cobra-29s.223406/ the jumper I am talking about is jp32 I have a old cobra 29 that doesnt work jp32 is the jumper he is talking about removing but it isn't in the radio I'm trying to do the mod to
Ah
Yes now I get it.
I have no idea what the new AM FM Cobra radios are using for the board.
Give it a minute and see if anyone here has played with the new model.
Posting pictures of the board in your radio may help.
And welcome to the group.
73
Jeff
Quick question the mod in question is just changing the voltage going to the driver to in turn change the dead key I'm still learning so if you laugh I understand I just love radios and would like to learn more you know not just doing a mod and not understanding what it's doing if you understand me but if that's what it does could we get the said voltage elsewhere?
Yep. A fixed resistor with an electrolytic capacitor in parallel with it permits the full peak audio voltage to reach the driver while holding the carrier down. A NPN transistor in place of the resistor makes it variable. I know we put a carrier control into one or another new radio like that. Had to cut a foil trace to interrupt the modulated B+ to the driver's collector circuit. Had to add a bypass cap, since the driver "shared" the one on the final's collector choke.
Might not be the one you have but I'll check our photo archive.
73
Thank you nomad for any info you shine on me like I told Jeff I been into radios since I was a kid popping finals watching the magic smoke come out just would like to understand it more everything i learn from you guys is for my learning purposes no one in my family really seen my passion for radios and one night while at a techs house that I knowed he asked me one night he said why you bring your radios to me sounds like you know how to tune these radios up and they sound good and I said really and he said yeah really and I replied to him I love radios and was hoping you would learn a young pup like me a few things well life happened and sadly a few weeks after our conversation he had a heart attack I miss him so much and all his story's of the war he told me he told me that's what he did when he was in service is work on the radios for the military and I thought that was so cool I am not spelling his name right but Checo is how you spell it you will be forever missed by me and wish I could have learned just a small piece of what he knowed
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I still have the wattmeter he gave me cause I said I didn't have one sadly the meter quit so I figured out how it works and made my own with the parts from the Checo meter to make mine in his memory sorry I haven't replied much I have to take care of my parents and what little time I get I play with my radio thank you Jeff and nomad for talking to me and hopefully one day we will talk on the airwaves once I save up the money to get me a little amp to learn
I wanna say Thanks again Jeff and Nomad
73 Chrome Cobra ( Aaron )
I wanna say Thanks again Jeff and Nomad
73 Chrome Cobra ( Aaron )
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