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ALL, unique problem.. radio recapped. working great with good rx and tx.. then after about 1/2 hour or so..channels of 4,8,12,16,20, and 23 kind of stopped working... but not really .. signal via signal generator went from s7 down to about s3.. also tx power went down.. all other channels are ok.. only thing common to all those channels is a 8.533 mhz xtal.
can a xtal heat up and stop working somewhat?
very baffled with this one i can post a schematic if needed..
Skip
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If that is the common denominator, then it probably is connected with that Xtal. If it is socket mounted, I would try cleaning the socket and pins. I'd also look at the soldering relating to the socket and / or the Xtal. If all that fails, then try another Xtal.
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Ok thanks Xtals are soldered in place kind of hard to get to but not impossible..
I will fire it up this morning to see if it starts working again.. if so how long it does work..
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City: Wellborn Florida
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You might also get a can of "freeze spray," fire up the radio, and wait until the radio craps out, then spray in little puffs on the Xtal,, and any associated circuitry, and see what happens. If the problem is temperature related, that is, if a component fails after it reaches a certain temperature, this can help track down the component. When it cools back down, it may well start working properly again. This will tell you which component is bad.
(This post was last modified: 10-16-2021, 02:08 PM by
mikethedruid.)