Re: Small CRT Questions

Nice!

This was my first entry into electronics as a ~13 year old, trying to make a large black and white TV into such a "scope". It worked, sort of. Not very well of course due to the coil inductance. But I got a waveform displayed without killing myself.

"John Devereux"

I did the exact reverse at age 16.

Having built a very basic valve scope with a Philips 3 inch tube,

I decided to connect it to the internals of my 17 inch B&W TV - after a few false starts and a few * sparks* I was very delighted to get a small green and black viewable pix.

I still have the same scope and it still works.

Got 5 more besides now.

..... Phil

You killed yourself without getting a waveform displayed?

I made something like that with a WWII (or maybe Korean war) surplus

Lovely little tube.

Not very pleasant watching shows in green and black, IIRC.

I seem to recall, later on, hooking up a UHF tuner and a ramp generator to my (bought) scope, so as to get a tiny dim green unstable picture. Not sure exactly how I could have done that now, since there is no way I would have known how to make a sync separator. Must have used the scope TV trigger for H and manually "tuned" the ramp generate for V.

I've never made a valve circuit, looks quite fun now, from my older perspective.

I used the video out from my old 'Panoramic' Spectrum analyzer to feed a scope to watch TV. I would set it for a slow sweep from 54 to

I still have an old Ball Hercules monochrome vector monitor. It went with my first 286, which was a cool Everex. The display was in a cardboard box. The one it shipped in. What I refer to is a bare tube with a nine pin D-sub soldered on to the end of some wires attached to it. I still have a few of the ISA monochrome adapter cards too.

Great company video here on how Tektronix used to make their own CRTs in-house.

Best regards, Spehro Pefhany