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Old 17th Nov 2019, 3:33 am   #10
FStephenMasek
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Join Date: Jul 2011
Location: Mission Viejo, California, USA
Posts: 142
Default Re: F. Stephen Masek's HMV468 restoration

It is alive, at least from the 3rd valve through to the speaker. I was able to connect a signal generator to the grid of the 3rd valve and heard the 400Hz tone in the speaker. It had a VP4A in the 3rd position, instead of a VMS4B. I tried switching the VMS4B in the 1st position into the 3rd position, with the same result. That tells me both valves work, at least somewhat. The MH4 oscillator becomes warm, but I've not yet determined if it is oscillating.
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