Cobra 29 ltd Mod or Linear ?

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Cobra 29 ltd Mod or Linear ?

Post by SinStp » Tuesday 19th Aug 2008, 18:22

Hello all , I have been looking thru all the old posts and was curious. I have a new 29 ltd classic and am looking to extend my range. Are the final, swing , modulation kits and mods worth the trouble or should i just get a cheap little amp like the ones from rm italy. I would love to tear into this thing but i dont want to effect the reliability of my new radio. Is the final upgrade and swing kit comparable to say a 40 watt amp ? Thanks

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Post by absorbentgnome » Tuesday 19th Aug 2008, 23:59

Hi sinstp

First check the loudness of your modulation on another cb, and note how you are most probably not bleeding over onto adjacent channels at the moment and the audio is clean. If the cb you are listening on has poor filtering and you are getting bleedover then get someone further away to check for you. You may wish then to adjust the modulation so you are louder, but not distorted and not causing interference to adjacent channels.

Then I would do one of two things:

1. Get a small linear ~50W with a 5W input. You will be driving it near to full power as your rig has 4W output. Benefit of this is that its cheap and easy. You may run the risk of overdriving the amp if the modulation or power has been turned up too much in the rig.

2. Get a larger 100-200W linear with a variable power control. These typically need 10W to drive to full power. You will need to increase the power output from your rig to drive one of these close to full power. Personally, I would increase to about 6W. There are a number of benefits of driving an oversized amplifier. A nice clean distortion free output is one and the other is reliability. Also you won't burn your hand off if you pick it up after an extended conversation.

I tend to work with FM and SSB mostly, not AM so hopefully i haven't made any glaring mistakes there.

If you are talking locally then don't use the linear. Where I am, everyone talks on ch19 to each other often with burners when they don't need them so all you hear is people keyin g over each other, effectively making it useless for calling someone who isn't on your doorstep.


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cobra 29 mod

Post by WARLORD136 » Monday 25th Aug 2008, 9:10

keep your dk about 1 to 3 watts, get your swing hi, 15 , 20, whatever, and get a fatboy amp. a 350 variable, a 500, etc. just because an amp says hi=drive, doesn't mean it needs a lot of watts. it just means that it is capable of handling them. i run a 1x6, all 2879's, (hi=drive), with a galaxy 2517 set at 1/2 watt dk swinging 22 watts, and get 1475 watts pep output on a dosy 4002 psw meter.
WARLORD 136 <> some people are affraid of the dark---some are affraid to leave it<>

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