Re: TK-931HD Wide Xmit Drift on Cold Power Up: Normal or a Problem Hi Stewart,
Just some shot in the dark comments... If there are no problems with the vco or synth operation then you might check the diagram to see if there is some sort of internal temp comp (heated) reference source. Your problem could be anything from normal operation (for that type of radio) all the way through some obscure part with a thermal drift issue as/when power is first applied. Percision voltage regulators, crystal oscillator references, vco alignment... yadda, yadda. Compare the radio to another just like it (if possible). If another radio doesn't have the same problems you've probably removed the warm up drift as normal part of the question. The issue then becomes how practial is it to trouble shoot the radio? Unless another same model radio is stable right out the starting gate I would probably expect an older 800/900 Mhz radio to have some type of reference requiring at least some type of short warm up time. But a look at the diagram would best tell the story. You might also consider a simple radio air blow-out and basic vco and/or synth alignment / check-out. Marginal synth/vco lock is also a culprit... and you can possibly look at the steering line voltage for helpful clues. cheers, skipp ps: Someone gave me a tk-931 on a trade-in the other day. But I can't get the program/software to read it so I've shoved it on the shelf for the moment. Maybe later we can work through the stable set up time because I was interested in setting the radio up on Amateur 900 MHz for a friend. > Stewart Rabinowitz <[EMAIL PROTECTED]> wrote: > Hi, Skipp: > About 75 degree F. before and after. >
