[EdHolland]

Good points, Arran. I haven't encountered this problem with any other radio (all earlier vintages), so am learning here. It is a benefit to have everything screwed together, rather than riveted.


All the cans are done, and all seems well through the RF chain, but I still have one persistent, and very intermittent "pop" which seems to plague AM. One thing I notice when this occurs is that the neon indicator in in the bench power strip flashes. It usually doesn't light (the thing is old) but there is a coincident flash when the radio lets forth a pop from the speaker. The pop noise is controlled by the volume pot, so it is either a strong interference from a fault in the AC circuitry, or something faulting in the HT line.

Whatever and wherever it is, it's very hard to locate. I disconnected the cap across the line (an old ceramic disk) - no change. Poking and prodding under the chassis doesn't seem to provoke the trouble repeatedly, although sometimes it seems there could be an effect. Not convinced. The line cord and all internal mains wiring has been replaced.