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hurricane
Posted on Wednesday, November 21, 2001 - 6:50 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I have a radio shack trc-485 that i really really like. i know they may be junk but i like it. well we tuned it up a little and well maybe a little to much, and it burned up on me. i was using it one night and it started smoking. now it has no modulation, my question is, would it be worth it to have it fixed. would it be possible for me to fix (if someone talked me through it). does anyone have expirience with this make and model with this problem? could it be a simple fix as like replacing a chip or diode or a capacitor, ect? thanks in advance for any help.
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307
Posted on Thursday, November 22, 2001 - 10:13 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Most likely you cranked up the bias to high and caused a heavy load on the AM regulator. It is most likely reparable however it is not something I could walk you through. Take it to a CB shop and tell them to replace the AM regulator and the Final/Driver if needed. But tell them also to set the bias of the driver / final at about 200 mA on RX.
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hurricane
Posted on Thursday, November 22, 2001 - 12:13 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

thanks for the info 307.
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Sitm
Member
Username: Sitm

Post Number: 77
Registered: 1-2004
Posted on Wednesday, March 31, 2004 - 3:34 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I have a trc 485 that was tuned on a scope by a actual licensed tech. It dead keys 9.75 on digital watt meter. I don't know what it swings. But my local group (who don't know I have it) have told me they are certain that it is a converted ham radio because of the clarity of the radios modulation. So turn that puppy right and keep it. I have had mine for many many years.

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