18-10-2018, 08:21 AM
The rectifier is working, at least to some extent. I connected a dummy load (25R WW resistor) to the output terminals, warmed up the rectifier and turned on the output switch. I was rewarded by a modest blue glow in the rectifier and a very small voltage, less than a volt, at the output. So nowhere near 100% yet but at least it's heading in the right direction.
It's on the variac at the moment, I need to establish the correct operating voltage, probably by measuring the rectfier filament voltage. Then choosing the correct primary taps. As I wind up the variac the transformer starts to hum so for now I've left it at that point, just starting to hum. Another way might be to measure the primary current, wind up the voltage until it starts to rise steeply due to saturation and then back it off a bit.
I may need to make up some kind of stand to do any more work on it. Almost all the places I need to connect a meter are behind the panel but it won't sit safely except on its back. The rectifier and baretters stick out too far for it to sit on its front so either needs to be supported on its front spaced off the bench or on its side with the heavy transformer trying to pull it over.
It's on the variac at the moment, I need to establish the correct operating voltage, probably by measuring the rectfier filament voltage. Then choosing the correct primary taps. As I wind up the variac the transformer starts to hum so for now I've left it at that point, just starting to hum. Another way might be to measure the primary current, wind up the voltage until it starts to rise steeply due to saturation and then back it off a bit.
I may need to make up some kind of stand to do any more work on it. Almost all the places I need to connect a meter are behind the panel but it won't sit safely except on its back. The rectifier and baretters stick out too far for it to sit on its front so either needs to be supported on its front spaced off the bench or on its side with the heavy transformer trying to pull it over.
www.borinsky.co.uk Jeffrey Borinsky www.becg.tv
