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macona
06-16-2010, 03:18 PM
Its amazing what you can find at the scrap yard. Got this pile of goodies, new high purity valve, new fore pump isolation valves, kf-40 vacuum valves, adapters and all sorts of stuff. Also got a nice DC gear motor that looks new.

http://farm5.static.flickr.com/4024/4692861442_9f2d3ffb06_b.jpg

Not from the scrap yard, I got a new toy as well. An old Inficon Quadrex 200 RGA. Thing is 26 years old and still works. Looks like the turbo pump it was attached to must have failed and they never bothered with it. Attached it to my system and it fired right up. Even with the older control its a step up from my Dycor 100AMU unit. This one is 200AMU and has the electron multiplier option. Even though it has been exposed to air for who knows how long it is very sensitive. In leak check mode I can spray a touch of helium in one of the basically new copper sealed valves that go to atmosphere and in a couple minutes the thing goes off.

its had a long life, started out at Tektronix and then off to Triquint. It also came with a whole bunch of conflat adapters, KF clamps, and even a spare filament.

http://farm2.static.flickr.com/1286/4692228587_058b5a21b3_b.jpg

http://farm5.static.flickr.com/4046/4705133891_105422f674_b.jpg

tdkkart
06-16-2010, 03:41 PM
OK, so WTF is it??

bob_s
06-16-2010, 04:22 PM
real time gas analyzer

John Stevenson
06-16-2010, 04:26 PM
It's for determining the sex of licorice allsorts.

.

bob_s
06-16-2010, 04:31 PM
John:

Best to have one around so that you can prove to the wife that its really the dog that's flatulent.

macona
06-16-2010, 04:49 PM
A RGA is a residual gas analyzer, also known as a quadrupole mass spectrometer. It can tell you what is in your vacuum system and analyze gasses. Also can be set up as a leak checker to detect helium or any other gas you choose. It filters gases or vapors according to their atomic mass. A molecules are ionized and sent down a path between four rods. A DC and RF signal is applied to the rods and depending on the charge and frequency of the rods certain ions are allowed to pass to the sensor. The sensor can be something as simple as a plate called a Faraday Cup or something way cooler, an Electron Multiplier. Whichever sensor you choose, a preamp picks up the signal and it is processed from there.

http://en.wikipedia.org/wiki/Electron_multiplier

Hydrogen being mass 1 and Oxygen being 16. So in a RGA water will show up with a primary peak of 18 AMU (Atomic mass units). The ionization causes some of the molecules to fracture and you will also have a smaller peak at 17 AMO (HO) and a tiny peak at 1 AMU (H). Thanks to this fracture pattern you can determine what kind of gases or vapors are floating around in your system like oils and solvents. You can also monitor process reactions. As I mentioned before it can be also used to check for leaks. I set it to look for mass 4 which is Helium (He2). Helium is used because it seeps through darned near everything. Then I use a bottle of helium with a low flow though a hose to "spray" suspected leaks like joints, valves, and welds. If there is a leak the RGA picks up the helium and sets off an alarm with a tone scaled to the intensity of the leak.

This unit I have will pick up masses up to 200 which covers a lot of hydrocarbons as well as some more interesting gasses like Xenon.

Here is a screen shot from my newer, smaller, but less sensitive, RGA. It just connects to a computer. The latest one does the same thing but on a little monochrome screen. You can see peaks at 18 (H2O), 28 (N2), and 32(O2), 40 (Ar) and three peaks above 40 that are indicative of vacuum oil in the system.

http://farm3.static.flickr.com/2607/4217937288_a685f29501_b.jpg

millwrong
06-16-2010, 05:24 PM
I would LOVE to see photos of the scrap yard you're playing in! Whatcha doin' with the coils that are in the photo?

japcas
06-16-2010, 05:29 PM
Neat stuff. Way over my head though. Every time I see a post like this with all of this high tech talk I can't help but think of this video.

http://www.youtube.com/watch?v=rLDgQg6bq7o

beanbag
06-16-2010, 05:30 PM
just what kind of "scrap yard" is this that has all this high tech stuff?

lugnut
06-16-2010, 05:55 PM
macona, it looks like you might have been to Burcham's Metals in Albany Oregon. they sell all sorts of things like you have there. Lots of industrial parts and bits.
For those that like that sort of things here is a link to thier web site.
http://www.burchamsmetals.com

macona
06-16-2010, 08:34 PM
I have been to Burchams but this is not where this stuff comes from. I really cant say where though. I think Burchams gets a lot of their stuff from HP.

Coils? You must see the heaters. Those are for heating up the tubes and pipes on the vacuum system to drive out contaminants.

Liger Zero
06-16-2010, 09:06 PM
It's for determining the sex of licorice allsorts.

.


:D Beverage ejected from nose. I need a tissue.