looking for rare high-Z low-capacitance coax - RF Cafe Forums

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gvisser
Post subject: looking for rare high-Z low-capacitance coax Posted: Wed Oct 14, 2009 4:58 pm

Lieutenant

Joined: Wed Oct 14, 2009 4:49 pm
Posts: 3
For a physics research application at Indiana University (Bloomington, Indiana), I am in urgent need of a short length (5 feet is enough) of low capacitance coaxial cable.
The ideal type would be RG-114 (M17/47) which is 6.5 pF/foot, Z0=185 Ohm, air/polyethylene.
However, anything <= 12.5 pF/foot would be very useful.
Does anyone have a line on where I can purchase (new or surplus) or otherwise get something like this? Please respond if you do... Thanks!


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flyingbrit
Post subject: Re: looking for rare high-Z low-capacitance coaxPosted: Mon Oct 26, 2009 3:37 pm

Lieutenant

Joined: Mon Oct 26, 2009 3:32 pm
Posts: 1
The typical car radio replacement whip antenna will have about 6 feet of RG-62A. At 93 ohms and 13.6 pF/ft it is not quite what you want but is easily available at your local NAPA store.


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gvisser
Post subject: Re: looking for rare high-Z low-capacitance coaxPosted: Tue Oct 27, 2009 10:04 am

Lieutenant

Joined: Wed Oct 14, 2009 4:49 pm
Posts: 3
Thanks - yes this is true and I'm aware of RG-62(A) and we have some of that around the lab. Really what I mean is that I'm seeking something better (lower capacitance) than RG-62. I have no idea if RG-114 ever was really made? But if there is any lead where to get something like that, or other special low-capacitance cable, I'd still like to hear about it. [I am also aware of a 125 Ohm foam polyethylene cable - 9.5 pF/ft - made (supposedly) by CommScope, but have had zero success in trying to get some of it. I suspect although they have a datasheet on the web, they don't really make it?]


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yendori
Post subject: Re: looking for rare high-Z low-capacitance coaxPosted: Wed Oct 28, 2009 5:46 am

General


Joined: Thu Sep 25, 2003 1:19 am
Posts: 50
Location: texarcana
Have you tried here?

http://www.awcwire.com/ProductSpec.aspx?id=RG114-Coaxial-Cable

Rod


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gvisser
Post subject: Re: looking for rare high-Z low-capacitance coaxPosted: Fri Oct 30, 2009 4:49 pm

Lieutenant

Joined: Wed Oct 14, 2009 4:49 pm
Posts: 3
Hello Rod,
Thanks for the lead! I had not found that one. Indeed they do have the stuff in stock, now it is only a matter of the minimum order $$ but that is for now my project manager to worry about.

In case anyone out there has a short length (5 feet is really enough) I'd certainly appreciate to hear from you. But I'm glad to have found a vendor that we can get it from. Thanks again!



Posted  11/12/2012