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Old 19-02-20, 04:20
David Dunlop David Dunlop is offline
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Join Date: Feb 2006
Location: Winnipeg, MB
Posts: 3,384
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Hi Bob.

I wondered a bit at first also, but then realized I had three dead valves between two different receivers. I did pull the second 12Y4 from the parts receiver, checked it and tried it in the Remote Receiver. It lit up and behaved beautifully!

On the down side, however, when I found the supply of NOS valves I bought a couple of years back, only one 12Y4 was in the bunch. It is now also in the Remote Receiver and running just fine. Quite a difference in performance in the Remote Receiver now, but still a ways to go with tweaking.

One interesting possibility has come up from some experts down East and in the UK. These valves go through a lot of heat up and cool down cycles when in use over time. The constant expansion and contraction cycles can eventually pop the soldered leads inside the valve base pins loose from the inside of the pins, causing the circuits within the valve to go into an open state. It has been suggested I try heating the pins and reapplying a dab of solder to the pin tips. This can often restore the valves. If not, and the two remaining valves in the Main Set Receiver are dead...not good. There be no spares at the moment.

Cheers,

David
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