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29 swing mod on 2000 ???

1iwilly

Sr. Member
Dec 7, 2008
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TGIF to all has anybody tried or done the swing mod from the cobra 29 to cobra 2000 gtl or 148
curiosity is sitting on my right shoulder while on my left shoulder is saying get off the meds LOL
i might just give this a try this weekend looking for input. i see it as it is cheaper than buying a camaro and modifying it if I don't modify something I'm going to lose it had to throw in some humor
 

TGIF to all has anybody tried or done the swing mod from the cobra 29 to cobra 2000 gtl or 148

The Cobra 29 radio uses a voltage step-up transformer to modulate the driver and final transistors.

The 148/2000 radios use a totally different modulator circuit for AM. Making it 'swing' is different as a result.

To control the carrier in a 29, parts must be added for this, since it is not built in.

The 148/2000 has a carrier control trimpot already built in. Hijacking that circuit with a diode and a resistor will make it 'swing'. And making the carrier level variable from the front panel involves cutting a foil trace and running three wires to the control.

Different radios. Different modulator circuits. Different strategy for modifying how each one performs.

73
 
ok originally i started with exithirteen asymmetrical mod I was happy with the audio quality but for me, i needed to see a few more watts not much gain but good enough for me so i install the cobra 29 swing mod my 2000 last night i couldn't wait for today yes i lost about 3 watts on SSB but no big deal for me as i don't talk on SSB AM only
got a few radio checks with good results all limiters still intact. and it's clear sounding with stock mike i have an electric element coming for my D104 will test with that. instead of using tp7-final, i use tp8 on the driver side you have to take v10-am power and turn it wide open as the new pot from swing mod is the new power control
 

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20210619_121548.jpg from 12 watts SSB down to 9 watts on SSB going to make much diff nothing a simple wire put back can't fix i just wanted to try something diff i found the info on cb tune up manual


Hey, if you don't care about sideband, go for it.

Always more than one way to skin a cat.

73
 
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Id rather have the Camaro ..Firebird, Mustang, even a Cobra, anything but an old cigarette smoke filled Foreign filled with whoknowswhat Cobra

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