Sonora roundie on ebay

[Eric H]

Found the Sams, here's a pdf file.

Seems to have DC Restoration and dig that crazy High Voltage section, don't see a 6AU5 horizontal output that often!

http://www.vintagetvsets.com/schem/Sams97A-13.pdf

[jeyurkon]

Thanks for the scan! The HV is odd! The audio section seems a bit underdone also.

John

[jeyurkon]

Well, I'm glad that I picked it up. It would never have survived shipping. The CRT strap wasn't tight.

Someone wrote the tube types on the chassis in pencil. Guess they must have found it easier than using the location chart.

It doesn't use a patch cord. Instead there is a jumper on the back to interrupt the power when it's removed.

The CRT is a 12LP4A. It appears to have a single field ion trap on it. I thought these required a double field trap.

The CRT showed no emission even after letting it run at a higher heater voltage. So I attempted rejuvenation. This brought it up to where it may be usable.

The odd part is though that now when I test for emission it starts at 340 uA and then gradually drops to 250 uA over about a period of a minute.

John