The Defpom Forum, for RadioMods, S&M Software and Music by The Defpom

Thanks Rick, that seems to have done the trick. Couldn't source a C1923 but a general purpose NPN BC548 is sitting quite happily in its stead for now.

73's nd Tnx fer info..

de 5XX qrx

I have exactly the same problem and its driving me nutz as well.
I must be thermal instability somewhere but I can't find where.

I also notice that vr15 the SSB ALC preset is non responsive
so it leads me to think that the intermitant fault lies in that chain somewhere.

Any ideas folks..