[TinCanAlley]

Originally Posted by jr_tech

I can't tell much from the fuzzy picture, but I suspect that the "ground" terminal of the tripler is connected to ground only through the 500 ohm resistor and series zener diode as well as the pot and 10 ohm resistor.
Even if the 500 ohm resistor were connected *directly* to ground that would not short out the diode, as there can be a voltage drop across the resistor if current is passed through it. Do an ohms law calculation and you can determine how much current is needed to raise the voltage to the zener voltage.
jr

Here's a better picture. The red outline is the ground post for the diode and spark gap. The yellow outline is from the 500ohm resistor on tripler ground connection, other lead of the diode, other lead of the spark gap and terminal one of the brightness limiter pot. The wiper of the pot goes to base of ABL transistor and terminal two of the pot goes to ground. The green outlines are the spark gap and the diode.

The reason I'm going though all this that I am not an expert in electronics and am still learning. Until I can understand how all these connections can work when they all seem to go to ground and not one of them seems to have any connection to a power source. If I can understand where the voltage for the diode and transistor bias is coming from, it will help me greatly. Is there voltage on the ground terminal of the tripler?