I pulled out the power supply last night and gave it a look over.
I find it interesting that all the tube sockets and held in my screws rather than rivets. Same goes for the terminal strips on the main chassis.
The 10,000 volt HV/EHT supply is an RF type and regulated using an 0C3 gas tube for a reference. A 6SN7 tube is the blocking oscillator and the HV output is sampled using a 180M voltage divider. The coil primary is driven by an 807 tube - precursor to the 6BG6. The only early B&W set to have a regulated supply to my knowledge.
The 807 has gone to air so I'll need to track down a replacement.
Also, the B+ delay relay coil is open
Not much work needed down here otherwise. The brunt of the B+ filtering is done by two huge filter chokes. Just three 40uF caps do the rest.
