Hermetically sealed BNC

Hi all, I'm looking for some panel mount BNC connecters that are hermetically sealed. This in not high vacuum, but what I'd call thermal vacuum 10^-4 -10^-5 Torr. I recall these ones we used in grad school. They had an O-ring groove where the base screwed into the panel. Searching the web I found some double female BNC connectors by Pomona. (I'd rather have a solder post on the other side.) And these by RF precission

formatting link
Scroll down to CX32136.. it says hermetically sealed but I don't see any o-ring groove.

And this by Radiall

formatting link
This looks like what I remember, but bit spendy.

Anyway I'm hoping someone has brand in the US that's not as much as the Radiall.

Thanks George H.

Reply to
George Herold
Loading thread data ...

cally sealed.

rr. I recall these ones we used in grad school. They had an O-ring groove where the base screwed into the panel.

I'd rather have a solder post on the other side.) And these by RF precissio n

=BNC

o-ring groove.

dp/1207553

adiall.

Hi George. This takes me back to my time a Cambridge Instruments, where ele ctron microscopes called for loads of coxial feed-throughs into vacuum.

The connections into the specimen chamber were mostly O-ring sealed BNC's. I think we got ours from Greenpar and Amphenol - everybody seemed to make t hem, though Farnell didn't usually stock them.

For the detection photomultiplier, we needed a higher voltage coaxial conne ctor, which I think we got from Radiall. I had a particular problem with th e electron-beam tester, where I used a fast focussed photomulitplier tube t hat needed up to 1.65kV, where the regular photomultipliers were selected ( by the manufacturer) to get by with 1kV or less

For the electron gun we needed much higher voltages and rather lower leak r ates.

Radial did do very high voltage coaxial connectors, but IIRR they weren't v acuum rated.

I think we ended up having parts made by a local glass-to-metal seal specia list, where the glass got precision ground after it had been sealed to the metal, and indium wire was used to create the compression seal. They'd make us up a batch from time to time - not cheap, but cheaper than t he Radiall equivalents. I mostly wasn't directly involved, so it's mostly i mperfectly remembered hearsay.

--
Bill Sloman, Sydney
Reply to
Bill Sloman

Hi, George:-

How about these?

formatting link

I see them as cheap as $13, with plenty of stock.

Best regards, Spehro Pefhany

--
"it's the network..."                          "The Journey is the reward" 
speff@interlog.com             Info for manufacturers: http://www.trexon.com 
Embedded software/hardware/analog  Info for designers:  http://www.speff.com
Reply to
Spehro Pefhany

If you really need a low leak rate, try MDC Vacuum Products for the BNC.

Steve

Reply to
osr

There is also Ceramaseal:

formatting link

Steve

Reply to
osr

tically sealed.

Torr. I recall these ones we used in grad school. They had an O-ring groo ve where the base screwed into the panel.

(I'd rather have a solder post on the other side.) And these by RF preciss ion

&s=BNC

t/dp/1207553

Radiall.

lectron microscopes called for loads of coxial feed-throughs into vacuum.

. I think we got ours from Greenpar and Amphenol - everybody seemed to make them, though Farnell didn't usually stock them.

Hi Bill, I think I paged through the Amphenol catalog today and didn't see anything. I never heard of Greenpar. But I'll give both a look.

nector, which I think we got from Radiall. I had a particular problem with the electron-beam tester, where I used a fast focussed photomulitplier tube that needed up to 1.65kV, where the regular photomultipliers were selected (by the manufacturer) to get by with 1kV or less

rates.

vacuum rated.

ialist, where the glass got precision ground after it had been sealed to th e metal, and indium wire was used to create the compression seal.

the Radiall equivalents. I mostly wasn't directly involved, so it's mostly imperfectly remembered hearsay.

I wonder if I could just drive a threaded BNC into a tapered threaded hole, with some teflon tape. (Hmm or epoxy bnc's into a pipe thread adapter dohicky.)

Thanks for the remembrances,

George H.

Reply to
George Herold

Beauty! Thanks. Mark me down for a beer (or beverage of choice) If you're ever in Strykerville we can go to the flip side for Abbots Deluxe wings. George H.

Reply to
George Herold

Hi Steve, thanks.. (those all look spendy) I didn't know the UHV people would stand for an o-ring seal. :^)

George H.

Reply to
George Herold

I like the look of those,too. I wonder how the Be/Cu contacts are joined to the Kovar terminal.

Resistance weld, maybe?

--
"Design is the reverse of analysis" 
                   (R.D. Middlebrook)
Reply to
Fred Abse

ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.