http://members.bellatlantic.net/~vze2pdtg/gc1005.JPG
Heath GC1005 clock I had 2 SP-352 with dead spots one completely dead
I converted the anode B+ to a voltage doubler then brought the voltage down
(just above flicker) using a 5K series resistor on transformer wire
(about 210 volts)
Digits came right up nice, been running 3 weeks that way now

Thanks to a member of this board he was able to spare 2 Sperry SP-726's for
the seconds last night
The SP-726 are single anode, 2 "side by side" are needed 22K on the anodes
I think it looks better with smaller seconds ?

-Joe