In article ,
Nicholas Bodley wrote:

Old buck, here. and been fascinated by CRTs ever since Life magazine in
the earlier 1940s had a custom gas-focused CRT made to teach the general
public about CRTs. No, I'm not kidding. Would love to know date of the
issue.

Gas-focused CRTs have a visible beam, and vary beam current to optimize
focus. They're obsolete, because their frequency response (CRT, not the
amplifiers) goes only into the low AM range, if that.

Anyhow, I see splendid examples such as my own curb-find spherical 21-
inch aperture-grille Diamondtron, a few flat-screen types, and a highly-
developed very-wide-deflection-angle TV CRT (Sony?) -- all put out as
trash to recycle. (Btw, just what *is* the deflection angle of that
really-short CRT? I have photos of it. Somebody took the yoke for the
copper.)

Doesn't somebody, somewhere, want to save one apiece of representative
samples of the big bottles? In a few decades, they will be amazing items,
really scarce, if any examples exist at all. (For instance, are there any
Zenith Flat Tension Mask tubes still in existence? (I'd guess, a few,
probably all unloved))

Fwiw, I used to own a burned-out Western Electric 224-B gas-focused CRT.
It had been hanging from the ceiling of the store of Blan, The Radio Man,
which was demolished to build the NYC WTC. Covered with lots of dark
dust, he sold it to me for something quite modest such as $10. It had
been a personal treasure I took good care of, and sadly let go in a time
of horrid personal crisis. (I'm essentially OK, now, if too reclusive.)

It must have been the CRT in the General Radio 'scope, the one with the
CRT in a separate enclosure with a cable to the main cabinet. As well,
it was very likely the first practical, low-voltage (hot cathode) CRT.

For more info, See Rider's Encyclopedia on 'scopes.

It's more than CRTs, but this place is well worth a visit:

http://www.pavekmuseum.org/