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Vanillagorilla
Member
Username: Vanillagorilla

Post Number: 57
Registered: 4-2005


Posted on Monday, June 06, 2005 - 9:07 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)


Hello Tech's! I posted this question in the open forum but nobody wanted to touch it. I decided to cut and paste my previous post here with the hopes of some kind of solution or troubleshooting ideas. For what its worth I have since installed a small (4") PC type fan under the radio where the internal speaker used to be and I seem to be able to do ok. I realize this is just a band-aid till I can get to the solution..here's the post:

After about 10-15min of modulating on and off the TR51 (2SB754) in the MOD circut gets hot and shuts down the carrier. If I allow it to cool a few minutes I'm ok till it heats up again then she starts cutting up and falling off again. I checked and resoldered the 3 pins on this "final"(Transistor?), unscrewed it, pulled it away from the side of the chassis and applied heat soak compound..still does it. Tightened all screws /grounds to chasssis. The radio is new and bought it "peaked / tuned". Radio does not seem to be over driven but has had the mod limiter clipped as per the seller. Any ideas here? I'm fairly knowledgable but won't go too far in troubleshooting something I've never encountered before.
Please...any and all suggestions would be great~!

Thanks for looking!
Hank '905
CEF 559

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