14-02-2019, 08:08 AM
I assume you have the circuit. It's Trader sheet 1273.
There are 2 rectifiers, a biphase one with 2 diodes for LT, a single half wave for HT. 1N4006 or 4007 with 100R is fine. Resistor value not critical.
Since there's a 3K9 resistor between the reservoir capacitor and the rest of the circuit that will drop the rectified HT significantly. I'd say nominal 90V (same as a B126 battery) after the resistor though not very critical as the battery voltage would vary over a fairly wide range as the battery ages.
If you haven't already done so, please replace the 10n capacitor (C23 on Trader sheet) that couples audio to the grid of the output valve. The original is likely to be leaky which could easily cause the audio output valve and transformer to suffer.
There are 2 rectifiers, a biphase one with 2 diodes for LT, a single half wave for HT. 1N4006 or 4007 with 100R is fine. Resistor value not critical.
Since there's a 3K9 resistor between the reservoir capacitor and the rest of the circuit that will drop the rectified HT significantly. I'd say nominal 90V (same as a B126 battery) after the resistor though not very critical as the battery voltage would vary over a fairly wide range as the battery ages.
If you haven't already done so, please replace the 10n capacitor (C23 on Trader sheet) that couples audio to the grid of the output valve. The original is likely to be leaky which could easily cause the audio output valve and transformer to suffer.
www.borinsky.co.uk Jeffrey Borinsky www.becg.tv
