I've almost got my RS124 together, and I've noticed that the tranformer I'm using, which came out of a V103 summing amp (core type), has a HT voltage which is way too high.. it's rated at 270 VAC at 16 mA.
I was convinced that I could use it with a drop-down resistor, but looking at the circuit, the variable current from the first stage might cause too much of a voltage swing, with an added drop-down resistor
I measured 450V DC with just a cap across the diode bridge and a 100K load. I'm assuming that under 16 mA load, it will drop.
Maybe two 100V and one 60V zener in series and a suitable drop-down resistor?
I was convinced that I could use it with a drop-down resistor, but looking at the circuit, the variable current from the first stage might cause too much of a voltage swing, with an added drop-down resistor
I measured 450V DC with just a cap across the diode bridge and a 100K load. I'm assuming that under 16 mA load, it will drop.
Maybe two 100V and one 60V zener in series and a suitable drop-down resistor?