09-10-2021, 04:22 PM
Well I have solved why I wasn't seeing anything on the tube.
I found my VCR97 and hooked it up so the beam current was around 100uA. Just to prove to myself that I was doing everything right and also to see how bright a the unfocused spot would be. And everything worked as expected. See first photo.
I hooked back up the tube in the telly. I When I connected it I just disconnected the heater, cathode, grid, and final anode leaving the X and Y plates connected.
I had thought that all the X and Y plates should be at the same potential and should be fine. But I was wrong as when I disconnected the X and Y plates and left them floating I got a spot. See second picture taken in darkened room.
It is dim and once it is spread across the screen I doubt it wont be visible at all.
Frank
I found my VCR97 and hooked it up so the beam current was around 100uA. Just to prove to myself that I was doing everything right and also to see how bright a the unfocused spot would be. And everything worked as expected. See first photo.
I hooked back up the tube in the telly. I When I connected it I just disconnected the heater, cathode, grid, and final anode leaving the X and Y plates connected.
I had thought that all the X and Y plates should be at the same potential and should be fine. But I was wrong as when I disconnected the X and Y plates and left them floating I got a spot. See second picture taken in darkened room.
It is dim and once it is spread across the screen I doubt it wont be visible at all.
Frank
