Okay, after much delay I did the experiment.pdf64 wrote: ↑Thu Feb 01, 2024 12:54 pm What I was looking for was the blue to brown resistance, and the blue/white to brown/white resistance.
Are you able to check the primary to secondary voltage ratios?
eg if a measured low V AC is applied to the 4ohm secondary, what V AC is produced across blue to brown, and blue/white to brown/white?
An isolated heater winding (5 or 6.3V nominal) could be used to provide the low V AC.
I used the 6.3vac tapping of a Classictone Trainwreck power transformer.
In channel A, I had 6.65vac on the 8 ohm secondary windings.
On the brown/white and blue/white leads (connects to class A EL-34’s) I had 149.3vac
On the brown and blue leads (connects to 6L6’s) I had 185.4vac.
On channel B, I had 6.65vac again on the 8 ohm secondary.
The brown/white to blue/white wires had 149.1vac
The brown to blue wires had 185.2vac
I hope that’s of some assistance.
The measurements were taken with a Fluke 77 that I purchased in the 80’s.