Thanks stajo, I do the measurements before the LL1660 so I suspect the problem is before the LL1660, Thomas Mayer told me not necessary the cap for this OPT in this configuration.
Hey guys I ned to drop 307VDC to 150VDC, who knows the reistor value?
Then find a way to drop your voltage and test without the gyrator.
Listen also to Stajo. Put a cap temporarily between gyrator and transformer, other leg to ground to see if something changes.
These are the tests I would make.
I would recommend that you do not try to "patch" it. Stop for a moment, and think of a proper solution.
For instance, if you want to use your output transformer, this is what you can do. Use a VR150 tube to get 150V at the transformer. Feed the VR150 tube with a DN2540 as a CCS set on 35mA max. Feed the DN2540 CCS with filtered 200V DC.
For instance, if you want to use your output transformer, this is what you can do. Use a VR150 tube to get 150V at the transformer. Feed the VR150 tube with a DN2540 as a CCS set on 35mA max. Feed the DN2540 CCS with filtered 200V DC.
157 volts divided by 0,005 A = 31,4 k. But then you really need a cap also cause this will act as anode resistor on top of your OPT. Which the gyrator also kind of does, but more like an inductor ie a choke. Now you have two "inductors" in series.
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Sorry Iko I don't understand you, could you draw a schematic? BTW I don't have any VR150 tube
Look in this thread for Andy's schematic. It is a really good solution, tried and true. Two VR75 tubes in series also work great, not to mention their glow is beautiful. I know it's frustrating because you're so close, but don't rush.
At the moment, if you really want to see it working, drop the voltage as the other guys said. But you'll need to fiddle a bit with the resistor values. Don't risk, use a power resistor. You will also need a high voltage capacitor, from the input to the transformer to ground.
At the moment, if you really want to see it working, drop the voltage as the other guys said. But you'll need to fiddle a bit with the resistor values. Don't risk, use a power resistor. You will also need a high voltage capacitor, from the input to the transformer to ground.
