[PaulR]

Thanks for the replies.

My question was brought about because of a Pye Music Maid clock radio which I recently brought back into use after several months. It worked for a while then started to hum badly because one of the original smoothing caps failed. I replaced them both in different positions to the originals and there is a bit of a hum remaining and I was not sure whether it was always there. It does have a UL41 output valve but I replaced that not long before another fault caused me to stop using it. The hum isn't too bad and I now think it must have been there all along but it made me think about putting replacement smoothing caps in a different place