• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Anyone know what this is?? Strange tube/ bulb.

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Magura,

Does an ohm meter show any continuity between the end pins? My initial reaction is that this is a small short arc lamp which would show no continuity. If that is the case a rather specialized power supply is needed to light it. It seems very dark. Unless that is a special filter coating the bulb has long use on it.

If you get no continuity try placing it in the microwave oven with a small glass of water to protect the oven for minimum load requirement. If it contains a noble gas like xenon under pressure it may glow for you helping identify the gas, and the lamp type. Xenon would glow whitish. Do not run for more than a couple of seconds.

I'd advise against "just plugging it into the 120 volt mains" in case it is a low voltage filament lamp. That will instantly ruin it.

Do you collect interesting vacuum tubes as a hobby? I do.
 
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Joined 2003
Not a photomultiplier.

It isn't a photomultiplier - they have a sequence of anodes known as dynodes that deliberately stimulate secondary emission at each anode so that the initial electron produced by the original photon is muliplied 2, 4, 8, 16, 32, 64 etc, depending on how many dynodes are present (ten is common). The dynodes look rather like louvres, and the valve has a pin per dynode, so they always need bases with lots of pins
 
Most certainly not a PM tube. Even if the voltage divider for the dynode chain was internal, which I have never seen, a PM tube is usually a sub-millamp device. There is also several types of dynode chains, depending on use.
I used to do PM tubes and photon counting for more than 20 years.....

Kind of looks like a Xenon projector lamp, though, as indicated...
I used to be a projector machinist in the very early 70s, but we still used arc lamps (!). Xenon projectors were part of the theory , though.
I actually have a license for such work...... makes me wonder where that is lurking..................
 
Maybe this info should have been included in the first place.

If you look at the first photo, you will see the dessignation in russian...the first 3 letters that is. I cant type those russian letters so youll have to look at the photo. after the 3 letters it says "-51". Does that help any?

The tube is brand new, one side is metallized for the sake of reflection (I believe), the other side is clear.

Cheers

Magura:)
 
rcavictim said:
Does an ohm meter show any continuity between the end pins? My initial reaction is that this is a small short arc lamp which would show no continuity. If that is the case a rather specialized power supply is needed to light it. It seems very dark. Unless that is a special filter coating the bulb has long use on it.

Ah, another good suggestion.

Nothing too specialized, you could test with a neon sign transformer and see what it does. For full operation you may need a current-limited 800VAC (OCV) power supply capable of oh... 20-50 amperes.

Xenon would glow whitish. Do not run for more than a couple of seconds.

Yes, interesting things happen when glass is in direct contact with pure plasma at 20,000°F+...


I'd advise against "just plugging it into the 120 volt mains" in case it is a low voltage filament lamp. That will instantly ruin it.

True. Good reason to use a variac and maybe transformer.


Do you collect interesting vacuum tubes as a hobby? I do.

I do, although I don't have a habit of seeking them out...

Tim
 

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Valve/tube collecting

Sch3mat1c said:



I do, although I don't have a habit of seeking them out...

Tim

Tim,

That Raytheon tube you showed looks like a waveguide mounted TR switch for microwave radar. I could not find it in TubeLore however. My second guess if that was wrong is a klystron for a laboratory microwave signal generator.

I collect interesting tubes and valves but probably as you, not by seeking them out. I just hold on to them as I acquire them and in all my years didn't throw many tubes away. Those that I did I am frightfully sorry for now. I used to have quite a collection of interesting small CRT's now long gone but my collection has come back in those a bit since my last move 7 years ago. I wouldn't consider myself a tube collector really. I have a bunch of the more interesting looking ones in a glass display case in my home as technological curiosities mostly. Vintage TV sets with round picture tubes....now for those I consider myself a collector! Much deliberate searching, travel and expense to purposefully drag a large quantity of those across the border and eventually home, although I haven't bought one in several years now due to having run out of space in which to display them. :(

Rob
 
Re: Valve/tube collecting

rcavictim said:
That Raytheon tube you showed looks like a waveguide mounted TR switch for microwave radar. I could not find it in TubeLore however. My second guess if that was wrong is a klystron for a laboratory microwave signal generator.

Yep, klystron. I forget what frequency (1-2GHz?) but it's in the mW range. I think TDSL has something on it. ... Yep, two from the Valve Museum and one from WPS. 1.5-3.75GHz, 140mW max.

I've wondered if I could use it as an esoteric tetrode instead.

P.S. I've got a cute viewfinder CRT... 1" diagonal.. :D

Tim
 
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