Cobra 29 NW ST low tx power/swr no calibrate

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Iceburg
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Cobra 29 NW ST low tx power/swr no calibrate

Post by Iceburg »

Radio has only .5 watt output. Mod is good. SWR will not calibrate.Cked my antenna with another radio. SWR on the antenna 1.2.Mic is good. Radio also chirps on keyup. Recieve is great. I can read a schematic but I don't have one. I only have a VOM and Watt/Mod/SWR meter. Any ideas on where to look.Man date is 7/99
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Chuck
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Rick
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Re: Cobra 29 NW ST low tx power

Post by Rick »

Best to read this first as it help us help you http://www.radiomods.co.nz/forum/viewto ... STING%20!!

What is the PCB number?

You could just try replacing the final as it sounds like a blown final.
I do not know the ref number for your 29 NW ST but if it is the same as the 29 classic it is TR14 (2SC2078). Hope this helps.

Rick.
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Iceburg
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Post by Iceburg »

Sorry Rick
Just a brain fart.
PCB A1218-1
PLL D2816C
This radio has a 1969 final in it. Would you know it that is stock? I would normally just take this in to a repair shop but the nearest on is 100 miles away from me. Any suggestions for a better final?
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Rick
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Re: Cobra 29 NW ST low tx power

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The stock final is 2SC2078 but to try and get a bit more out for the radio some one has fitted a 2SC1969. It is up to you which one you fit, the gain you will get with a 1969 may if you are lucky maybe about 1 to 2 watts in my opinion I would just stick with the stock final.

Rick.
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Iceburg
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Post by Iceburg »

Thanks Rick
I have found a 2cs1969 at a shop here, but it is a SUMITOMO and I am a little wery about the quality. I am still looking for a 2sc2078 but I am almost out of local options for that one. Will let you know how it works out.
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Chuck
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Rick
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Re: Cobra 29 NW ST low tx power

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RF Parts have them 2SC2078 and the Fake 2SC1969 in stock. I would not use the fake 1969 more trouble than it's worth. http://www.rfparts.com/2sc.html

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Post by Iceburg »

Hi Rick
I checked them out today and they have a $25 minimum for ordering parts. I would have to order 5 of them. If I don't find it I will most likely do that and then I would be able to spread the cheer so to speak.

This is a link I found that might be of use to some of the members. It is a list for cb's,parts and accessories.
http://www.cbcintl.com/suppliers.htm#CB ... CCESSORIES
Chuck
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Iceburg
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Post by Iceburg »

Got a 1969 final today and installed it. The radio is now back to normal. Got 6 watts deadkey and swr cal works again

Rick I would like to thank you for all your help and advice! :D
73"s
Chuck
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