Horizontal Drive waveforms on my 1950 Zenith porthole

[Mike Stamper]

C77 and C84 are both new. I pulled them and subbed the identical parts. No change. The "phonevision socket was corroded and measured 27 ohms across each connection. I bridge the connections and remeasured (down to 0.2 ohms). No change. Still running about 7500-8000 volts - not enough to drive my NOS 12LP4 to more than medium brightness. I subbed the 6BG6, 1b3gt, and 6w4 (all of which were NOS and tested great). No change in HV or brightness. I'm fast running out of ideas and patience. Too bad; otherwise, it's a great set.