ok, pretty happy with this now. Added a lot more filtering caps to try to reduce the noise and flicker, improved grounding (at least as best as you can on a breadboard) and tweaked the magnetic and electric focus a bunch more. I'm very happy with the result now!

For those wondering about the setup:
DIY HV supply is supplying 700V which is divided down for all the different electrodes in the vidicon tube, 600V on G5, 300V on G4 and G2, 65V on G3 for focus, -35V on G1 for beam current. 15V on the target. Raster is generated by two 555 timers set up as ramp generators and amplified/centered by two opamps. Output from the tube is amplified by a transimpedance amplifier, amplified again and then output straight to the Z input of the oscilloscope. There is no blanking during either vertical or horizontal retrace, neither on the vidicon nor output, which is less than ideal but works. Vertical frequency is around 40hz, horizontal around 10khz.

#electronics #vidicon #diy