Fourth Vivat PWM Part 3

Paul writes:

Latest photo РI  managed a few more hours today.

Marconi-No-1-Chart
Marconi No 1 chart on PWM.

Looking good, but I did a bit of an audit on these PWMs and not 100% good news. This one is indeed the last one to be restored and tested; but, the one on the far right of the stack still needs a ‘shed load’ of caps changing in the waveform part. Looks like I never finished it. Never mind, I bought plenty of caps some time ago.

By the way, the Russian 5R4GY rectifiers shipped directly last year work a treat. I ought to order more and also some of their 6AS7Gs when things are a bit more like normal again. Good valves and good value for money.¬†I’m also now running short of 6AG7s (the metal clad video amplifier valve).

We have no spare picture tubes for the PWMs so it’s ‘wing and a prayer’ time. They’re 10FP4A or equivalent.

Generally, Vivat needs valves for spares as well as on-going restoration – there’s many hundreds in service!

Still a lot to do . . .