GM3SEK Triode board modification
What follows here is the modification that will allow the GM3SEK triode board to work with a toroid type transformer that supplies the high volts for the anode, and, the supply for the tube heaters. (this might also include lows volts for control, such as 18vac for 12vDC relays)
The following information comes from Ian GM3SEK himself.
Look at
the "TRIODE BOARD" printing along the bottom edge of the board.
Immediately above the "R" in "BOARD" is a plated-through hole - this is
the warm-up control signal coming from U3 (LM555CN). |