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Crossbow
Posted on Saturday, March 23, 2002 - 1:28 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

The radio in the mini truck took a dump. It's a cobra 21 ltd classic. This is whats going on, when you key down the meter swings and when you talk into it, it modulates on the meter and you think you are getting out, but nothing. When it recieves the meter swings and you get nothing. tried a different mic , still does the same. Any suggestion on how to fix.???
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Taz
Posted on Sunday, March 24, 2002 - 10:32 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

maybe your antenna? coax? did you check swr's?
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Crossbow
Posted on Sunday, March 24, 2002 - 8:47 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Taz
I checked it on my base setup in the house where everything is good. swings when you key and swings when it picks up signals. Tx comes thru my puter speakers when i have them on, but not with this radio. anybody got any ideas.???
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Dx431
Posted on Monday, March 25, 2002 - 12:50 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Crossbow,
This may sound dumb, but, have you checked the P.A. switch?
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Taz
Posted on Monday, March 25, 2002 - 8:22 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

yes the pa, or rf gain or volume squelch check all the knobs
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Crossbow
Posted on Monday, March 25, 2002 - 11:24 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

DX431
No p.a. on this little cobra. still need help
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Insider
Posted on Monday, March 25, 2002 - 11:23 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

When you transmit, do you get a carrier received on a nearby radio? If so, then I would suspect a problem in the audio chain somewhere.

Just for the heck of it, have you tried a different mic on it?
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Ss8541
Posted on Monday, March 25, 2002 - 10:30 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

plug a spkr into the pa jack and let us know what you find for output on the pa when mic is keyed and rx output through pa.
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Crossbow
Posted on Tuesday, March 26, 2002 - 6:25 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

don't have a pa jack and have tried 3 different mics
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Crossbow
Posted on Tuesday, April 02, 2002 - 3:43 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I guess the techs are stumped on this one
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Barakuda318
Posted on Tuesday, April 02, 2002 - 6:43 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

if you are getting no sound out of it then try your speaker, if no body is hearing you then check the microphon connetor inside, your audio wire has probly came loose, this will take away your audio and the audio of the receive, but if the meter is swinging when you talk, then I would suggest that the audio chip or a capacitor that runs it is toast, try replaceing the audio chip and see if that helps...good luck
73's
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Taz
Posted on Tuesday, April 02, 2002 - 7:00 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Its probly your speaker

how do you know if the speaker works?
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Sonoma
Posted on Wednesday, April 03, 2002 - 4:11 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

audio chip is the item I would check also.barakuda is in the right area.
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Sonoma
Posted on Wednesday, April 03, 2002 - 4:11 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

audio chip is the item I would check also.barakuda is in the right area.
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Taz
Posted on Wednesday, April 03, 2002 - 2:18 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Can you hear from the speaker? then you dont know it works!


start there, its also easyiest to replace
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Barakuda318
Posted on Wednesday, April 03, 2002 - 8:59 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Taz is right try the speaker or just wire another one to it really quick to see if that is the problem, if that is not the problem the the other things I mentioned are probly the culprit, trile and error as I always say, of course thats if you don't have all the equipment to check these things out, then again sometimes even the very best of the best, need trile and error to figure something out, good luck with your opperation doctor lol
73's
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Barakuda318
Posted on Wednesday, April 03, 2002 - 9:01 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I just thought of something, try the shield inside, at the mic connector or pcb board, I had a radio once that did the same thing you are describing and instead of it being the audio wire it was the shield, took me about 2 months to finaly figure it out, just came loose from the solder joint, good luck
73's
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Crossbow
Posted on Wednesday, April 03, 2002 - 9:22 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I put an extention speaker in the jack, no sound. What does a audio chip look like??? Where would it be located. The radio is a cobra 21 ltd classic
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Sonoma
Posted on Thursday, April 04, 2002 - 3:52 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I believe it is a ten pin ic mounted on the side of the case with a screw and the pins soldered to the board check the pins I have seen them come lse at the solder joint.if it is like the cobra 19 it will have a ic that looks like the pll.it try pushing on them and see what happens.it has been a long time since I have been inside a 21 so my memory fails me as to which chip it has in it
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Barakuda318
Posted on Thursday, April 04, 2002 - 12:14 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

The audio chip will be either a rectangular shape microchip or a trapazoid shaped microchip, they are usually located along the side of the chassis, in the cobra 21 I believe it is on the right side of the chassis, with the radio facing front of you speaker side up, looking into the radio were the components are, should be on the right side closest to the back of the radio mounted to the side of the chassis, good luck hope this helps.
73's
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Crossbow
Posted on Tuesday, April 09, 2002 - 8:20 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Thanks for all the input, but i tried everything and no go. I gave up and put it in the later box. Maybe later maybe not.
Thanks Again
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Bigbob
Posted on Friday, April 26, 2002 - 11:39 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Am radios are relatively cheap,buy a new one and quit wasting your time.

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