Hi everyone ,I have a HF2500 with a weird problem ,after the 2 min. warm
up period the amp will stop keying if you key it a few times in a short
period of time. The 15mfd cap that is part of the delay circuit using a
555 timer charges back up about .5 volts each time you key the amp if
you charge the cap above 4 volts the amp quits keying until the
voltage decays below 4 volts .I replace the caps and the 555 and the
transister it drives and still the same .I tried a diode between the 555
and the 15 mfd cap and that fixed it but if you turn the amp off it
takes hours for the timer to reset and if you turn it back before then
the amp has no warm up delay . Years ago I had a problem with the time
delay circuit and Command Technologies told me about a factory service
mod that put a 15 k pull down resister on the 555 and I did the mod and
it has worked fine for years till this . Any ideas would be welcomed.
Glenn WW4B
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