Quote:
Originally Posted by dewdude
I really didn't want to go digging through that dusty, snake infested, spider infested, cobwebbed mess of a shed looking for the book. Still, after I looked more at the thing to see how the filaments are connected; I was confused. I googled for a while; could find nothing about this tracer.
So, back up the shed I went; and on the floor under a recently placed bin; I found the book; which was lucky because I expected to be up there a while and get bitten by something.
It's a Speco Model STAB. It actually used two batteries. "2-#2 flash light cells"; and any number of 67.5V batteries. There is also apparently a 1S5 tube in the probe; so I'll have to pull that apart.
I think I might actually have a transformer that puts out in the neighborhood of 60V; so I may be able convert it to AC.
schematic: https://flic.kr/p/nHDKWV
tech details: https://flic.kr/p/nFB9ih |
The B+ source is relatively easy to build, the 1.5 volt, high current supply is a little more difficult. The schematic shows that the filaments are wired in parallel.
BTW, the 3S4 is only rated for around 67.5 volts, plate and screen, so I would try to stay around those parameters.