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Basic Tune Up on a Cobra 29 LTD Classic

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Git_R_Done
Duckplucker
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Basic Tune Up on a Cobra 29 LTD Classic

Post by Git_R_Done » Tuesday, 09 December 2008, 5:01 AM

Ok I know how to do the mosfet mods but had a question about the basic tune up. How do you do just the basic tune up without the mosfet mod? the reason I ask is when my uncle gave me his radio I took the radio into a local CB shop and had a tune up done to it I witness most of it but from a distance I saw them desolder a resolder some componets most look like the blue electrolytic caps and a few other thing I know they tuned the coils and removed the L14 slug after all said and done it boosted my watts to about 25 on there meter and the same when I checked it on my meter. I have to Cobra 29s now the original one my uncle gave me its been tuned (by a cb tech) had the mosfet done by me and the schotty recevie mod also done by me and retuned all the coils for max watts which this radio has about 40-45 watts on my meter. My other radio all thats been done to that one is the mosfet mod and the schotty recevie mod and only put out about 25 watts but it hasn't had a tune up yet i would like to do it myself but need the onfo on it I really don't want to take it in and have it done and have to drop another $40 on the tune up for this radio so anyones help would be awesome thanks for reading this if it dosen't make sense just let me know and I'll explain it better


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Git_R_Done
Duckplucker
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Post by Git_R_Done » Tuesday, 09 December 2008, 13:28 PM

somebody has to know what I'm talking about

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preacherman
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Post by preacherman » Tuesday, 09 December 2008, 16:22 PM

When you say you have done the mosfet mod...do
you mean replacing the final with a mosfet...or do
you mean also removing R55 and R56 and C61?
If that is done, adjust the tuning slug in L14 for
maximum dead key and forward swing and
try adding some capacitance on the backside
of C59.

That's pretty much a basic tuneup. You can try stretching
the coil a little by the SO239. You won't gain much
by playing with the other tanks unless the radio is
in a bad state of tune.
regards,
preacherman

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Git_R_Done
Duckplucker
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Post by Git_R_Done » Tuesday, 09 December 2008, 16:31 PM

preacherman wrote:When you say you have done the mosfet mod...do
you mean replacing the final with a mosfet...or do
you mean also removing R55 and R56 and C61?
If that is done, adjust the tuning slug in L14 for
maximum dead key and forward swing and
try adding some capacitance on the backside
of C59.

preacherman


Yep thats exactly what I did. I did that to both radios I have. the 1st radio I took to a CB tech had the tune up done it gave me 25 watts without the mosfet then I installed the Mosfet mod and now its about 40-45 watts on my meter. the 2nd radio I never took to the CB tech becasue what I've learn from here all I've done to that one was the Mosfet mod but only get about 25 watts out of it I just wanted to know if I could get more out of the 2nd radio then just 25 watts


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