Thanks again for your replies. I'm clear now on how the muting control is supposed to work. I have started the refurb having completed the PSU/amp chassis yesterday which was straightforward - transformers and chokes all OK apart from needing to re-sleeve rotted and crumbling rubber-insulated wires, and replacing one HT cap that wouldn't reform. Interestingly I found a pencilled signature under the chassis from a long lost repairman dated 24/6/46 which is perhaps when some of the old radiospares replacement caps were fitted. The HMV manual specifies a 500mA HT fuse (Broadcaster Sheet says 1A
). I have fitted a slow-blow 250mA instead and will see how that goes. I only have quick-blow 100mA which I would guess might not survive switch-on surge. Jerry