I hadn't but the gm pcb uses a 100r "sense" resistor. I have put a 100r on the screen grid supply & have been having a think about this problem, but will do some experimentation first before coming to conclusions. TFW & for your input.
I like the feature to test the split filament tubes. Some tube testers just put voltage across the fil and not the tap. The tap is crucial in any radio that uses a pilot lamp across the rectifier filament. I really appreciate your explanation of how your circuits work. I still learn a bit on every one of your videos. I am wondering if a MOV circuit or an SCR crowbar might be able to damp the surge that blows the PS parts. That was one big arc in the 807. Maybe one of the varistors. I know Zenith used them in their TV sets for a long time. Take Care.
Glad you get something out these video's. A MOV might work but a crowbar may be too slow. I'm still not sure what it is that zaps the power supply. Is it an over current, over voltage or what? I haven't the test gear to catch & record events this fast. TFW.
@@diabolicalartificer I gave it a lot of thought- Do you think it might be a transient spike feeding back? Maybe an additional fast high current & voltage blocking diode in series with out feed of the PS to the tube.
had you thought of using a 100 ohm 1/4 watt resistor as a fuse in the anode supply
I hadn't but the gm pcb uses a 100r "sense" resistor. I have put a 100r on the screen grid supply & have been having a think about this problem, but will do some experimentation first before coming to conclusions. TFW & for your input.
I like the feature to test the split filament tubes. Some tube testers just put voltage across the fil and not the tap. The tap is crucial in any radio that uses a pilot lamp across the rectifier filament. I really appreciate your explanation of how your circuits work. I still learn a bit on every one of your videos.
I am wondering if a MOV circuit or an SCR crowbar might be able to damp the surge that blows the PS parts. That was one big arc in the 807. Maybe one of the varistors. I know Zenith used them in their TV sets for a long time. Take Care.
Glad you get something out these video's. A MOV might work but a crowbar may be too slow. I'm still not sure what it is that zaps the power supply. Is it an over current, over voltage or what? I haven't the test gear to catch & record events this fast. TFW.
@@diabolicalartificer I gave it a lot of thought- Do you think it might be a transient spike feeding back? Maybe an additional fast high current & voltage blocking diode in series with out feed of the PS to the tube.