FLYBACK TEST: (EDIT 4-14-19: CORRECTION, HV TRANSFORMER TEST, I’VE LEARNED A LOT SINCE THIS ORIGINAL POST) I really need the help of someone knowledgeable about these power supplies. Stock K40 supply with flyback mounted to board. This is a 100 to 1 high voltage interface I made awhile back for testing microwave transformers and I cautiously decided to connect it to my new tube. For every 10 volts on this scale, the actual should be 1000.
RESULTS: Sitting idle without pushing the test button, it is reading 2,000 volts. At 5ma, it shows around 10,000 volts, at 10ma, it was only doing 15,000 volts and finally at 15ma, it dropped to about 13,000 volts. Experts? There was a downward spiral the more I increased the current. Is this normal behavior for these? At 15mA, it would seem to be only driving the tube at 19 watts? What’s interesting is that just past the 4ma marker when it quits fizzing, the voltage jumps up and I was able to back it down close to 3mA to achieve 20,000 volts. Since I know very little about these supplies and how they behave - HELP!!!