Unidentified rack units with air pumps in them

[Aaamusements]

I have no idea what these units are. They were received with a lot of radio, comms and miscellaneous items. They might be related to this plotter/recorder unit as it was in a similar coloured surround I think?
https://www.vintage-radio.net/forum/...d.php?t=112588

These could have been part of some test equipment used by the Buildings Research Establishment but I can't be sure...

There is something square missing from the front panels, and the motor appears to be an air pump with two terminals on the front to attach rubber pipe to.

Any suggestions appreciated, thanks!

[Sean Williams]

Looks like a diaphragm vacuum pump - probably as part of a gas analyser?

[Radio Wrangler]

Clashed with Sean!

David

[Aaamusements]

Thanks... any ideas of uses for them? Either just the rack units or just the vacuum pumps. Or even both together!
Seems a shame to scrap them...

[HamishBoxer]

If they are standard 19" racks then they are useful.

[Aaamusements]

I will check the measurements.

[Bazz4CQJ]

I very much suspect it was part of an infra-red gas analyser. In the days before helium mass-spec was used for leak detection, it was common to use nitrous oxide gas and detect its intense infra-red absorption peak. I inherited a couple of complete units back in the day when I worked in the nuclear power industry.

B

[jimmc101]

I'm sure I've seem similar pumps in old vacuum desoldering stations, I'm sure somebody would want them.

Jim

[Bazz4CQJ]

I doubt they will exert sufficient suction; all they did was suck in a "breeze" of gas. They depend upon some soft rubber diaphragms which tend not to age very well and I'd guess they were made in the 50's or 60's. I have an identical-looking pump in my garage but I've never used it for anything. Might be useful for oxygenating a large aquarium? When I got the complete units, I did wonder if they could be adapted to analyse car exhaust gas (CO), but it would have been quite a conversion; they were gas-specific. IIRC, on the electronics side there were two or three ECC8x's and I think they worked by beating two oscillators against each other; the infra-red gas cell effectively being a pressure-dependent variable capacitor. They employed a constant-voltage mains transformer and the whole assemblies were pretty heavy! A complete one in working condition would be collectable; good example of a technology that was quite clever but was soon superceded.

B

[G6Tanuki]

Originally Posted by Bazz4CQJ

I very much suspect it was part of an infra-red gas analyser.

They do look like part of some sort of air-sampling device, or a device to feed a gas/vapour into an airflow at a controlled rate.

You could perhaps use them as aquarium-bubblers?