Reply to "Power for Circuitron switch machines"

I wired mine using the AC technique.  Your writing could be easily adapted to it with not much change.  I used the low voltage accessory ac output of my Z4000 and wired it through a couple of 1n4006 diodes to get the equivalent of your +/- 12v.  The instructions and schematic are in the tortoise instructions.  But that power supply from Amazon looks pretty slick too.