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Rodder54
Junior Member
Username: Rodder54

Post Number: 15
Registered: 12-2001
Posted on Tuesday, December 04, 2012 - 9:45 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

i have good dead key but no mod i have used different mics and still the same power is about 5 watts on a palomar meter and can dummy load 20 amp power supply
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Jrsmith
New member
Username: Jrsmith

Post Number: 7
Registered: 7-2012
Posted on Thursday, December 06, 2012 - 1:09 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

is the receive working properly? also make sure the amc hasn't been turned all the way down VR4. check D11. might want to make sure u have a known working microphone that works on another four pin cobra. just some possibilities. if receive is not working could be the audio amp
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Rodder54
Junior Member
Username: Rodder54

Post Number: 16
Registered: 12-2001
Posted on Thursday, December 06, 2012 - 7:09 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

i think D11 has been cut and i tried VR4 both ways and in the center ya tried other mics and i have a test mic tester no mod at all for the 129 thanks
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Rodder54
Junior Member
Username: Rodder54

Post Number: 17
Registered: 12-2001
Posted on Friday, December 07, 2012 - 10:24 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

can you tell me where the audio amp is located thank you after rechecking the receive it is not working good off and on i would say thank you
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Jrsmith
Junior Member
Username: Jrsmith

Post Number: 10
Registered: 7-2012
Posted on Saturday, December 08, 2012 - 12:57 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

sense D11 has been clipped your modulation as you might know is wide open. Question? is your rx working.
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Dale
Senior Member
Username: Dale

Post Number: 1907
Registered: 12-2002
Posted on Saturday, December 08, 2012 - 10:51 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

id say its in the audio ciricuts. being d11
is clipped you already have full audio.if theres
no recieve then the mic maybe wire wrong. the mic
also could have awire off the plug
dale/a.k.a.hotrod
cef426
cvc#64
454 [dx numbers]
38lsb
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Jrsmith
Junior Member
Username: Jrsmith

Post Number: 12
Registered: 7-2012
Posted on Saturday, December 08, 2012 - 6:29 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

audio amp is IC4 should be a 10 pin IC. this can get tricky if u decide to test the IC, i'm not sure of your experiance. you do have your dynamike turned all the way up? just checking. what year 29 is it? you can find a service manual online at cbtricks.com. this will tell you the pin voltages for IC4 as well as all other voltages. I would also do a good visual inspection of the unit. u should be able to tell if your receive is working or not I haven't come across a intermitant RX. it is possible though! good luck
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Jrsmith
Junior Member
Username: Jrsmith

Post Number: 13
Registered: 7-2012
Posted on Saturday, December 08, 2012 - 7:12 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I found another fix. no tx audio and pa not working, check to see if TR17 is turned on you might find it missing base volts check R70.
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Rodder54
Junior Member
Username: Rodder54

Post Number: 19
Registered: 12-2001
Posted on Sunday, December 09, 2012 - 12:38 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

i found that to but i didnt understand what they mean by not turned on it has a little volts on both sides i couldnt find R70 i printed that page out too i might toss that radio if i cant get it to work at first i tapped the board for a loose solder joint and rx would come on then now its just gone thank you
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Press_man
Advanced Member
Username: Press_man

Post Number: 696
Registered: 5-2008
Posted on Sunday, December 09, 2012 - 4:07 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Checked c-112 ?
73 Pressman

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