20th Century Electonics LTD
DSQB/2 dual gun blue phosphor
11x11cm face, tube length 45cm.

20th Century Electronics LTD
S6SqG,M single gun, green phosphor
11x11cm face, length 45cm.

These two big tubes from the sixties have a similar construction. These were used in
the display unit from an electron microscope. One is a single beam, used for
display and probably having a green phosphor, the other a dual beam tube was
used for photographic purpose. One gun was used for the image, the other for
data, the phosphor color is blue into the UV spectrum for better recording.
20th Century Electronics produced 11 different CRTs but only two with a square
face, these are the two tubes.
Here a pdf with some additional electrical data. Thanks to Andrew Pierson for the
provided info.

Sylvania 5BRP25 5" radar Aviation tube
P25 orange long persistence phosphor (1972)
Used in military aircraft

AVIATION CRTs

M1224BP20
The Tonotron Aviation tube
Medium short persistence yellow-geen phosphor.
Made by Hughes Aircraft in 1956
Direct view CRT for storage of halftone images
The tube consists of two separate guns
and is sealed in a metal harness.

Philips 95483 medical 10x14cm CRT
Used in heart cardiogram display unit

MONOSCOPE CRT

RAYTHEON monoscope tube

Internal screenshot of the targetplate

Monoscope tubes were used in early computer
systems to generate symbols on a screen like
letters or numbers. This tube was probably special
made, the origin is airport Schiphol, in the tube you
can read KLM (the Royal Dutch airline)
This tube was kindly donated by Fred Vonk.