What do you make of this?

[boater sam]

Tuning Valve.  So what is it?



Its on the auction today.

Sam.

[Mike Watterson]

It's a little like a Klystron, but unlike any Kylstron I've had or seen.
The one I had looked like this WWII model:
https://www.radiomuseum.org/tubes/tube_cv35.html

Also
https://duckduckgo.com/?q=Kylstron&iax=images&ia=images

Especially https://www.radiomuseum.org/tubes/tube_cv237.html


Or perhaps an obsolete 'Backward wave tube', which are tunable microwave oscillators.
https://duckduckgo.com/?q=carcinotron&ia...&ia=images

Likely some sort of UHF to microwave device.

See also https://en.wikipedia.org/wiki/Extended_i...oscillator


Article on the first WWII Klystrons.
https://www.radiomuseum.org/forum/the_su...lator.html

Magnetrons are better known being the source today in a Microwave oven, but they are inherently pulse devices. The other kinds of UHF-Microwave devices are all amplifiers or oscillators.

[boater sam]

The silver knob on the end looks to be adjustable so maybe it is a backward wave tube.
I have never seen anything like it.
Is the number on the label a clue? It looks to be an Octal base with a valve holder attached.

[Mike Watterson]

A 5476 is British Admiralty store reference for NU30 / CV1278 silica rectifier.

Silica envelope vacuum rectifier. Used in radar modulators. Graded glass seals
60 kV anode voltage
0.8 A current
1.8 kW plate dissipation
90 mm bulb diameter

So obviously the 5476 isn't useful as a part number.

[MW0SEC]

Soft Sutton tube perhaps?

[Radio Fixer]

Article on the first WWII Klystrons.
https://www.radiomuseum.org/forum/the_su...lator.html

Interesting but really about construction. I still dont know how it oscillates.

Gary

[ppppenguin]

Dead link. It has been copied and pasted from a forum or elsewhere that strips out the middle of long links.

[Nick]

First British X band reflex klystron CV87. The double thread coarse & fine tuning mechanism was difficult to manufacture and the wide tuning range largely unnecessary for actual use outside of bench tests so comparatively few were made. The same tube and resonator structure was fitted with a simpler tuner for a smaller tuning range as the CV129, Cv223, Cv224 (different tuning ranges) and were used in early X band radar

https://www.radiomuseum.org/tubes/tube_cv87.html

[MW0SEC]

First British X band reflex klystron CV87. The double thread coarse & fine tuning mechanism was difficult to manufacture and the wide tuning range largely unnecessary for actual use outside of bench tests so comparatively few were made. The same tube and resonator structure was fitted with a simpler tuner for a smaller tuning range as the CV129, Cv223, Cv224 (different tuning ranges) and were used in early X band radar

https://www.radiomuseum.org/tubes/tube_cv87.html

Ah I was right in recalling the Sutton tube then, but not the 'soft' variety which was used as a T/R switch. Developed by Sutton & Thompson during WW2.