[time-nuts] Two pieces of old General Radio Freq. Nuts

Scott McGrath scmcgrath at gmail.com
Sun May 28 05:15:52 EDT 2017


The GenRad 874 connector was good to 4.5 Ghz  and took a Banana plug in the center conductor without changing electrical characteristics!!!

http://www.ietlabs.com/pdf/GR_Experimenters/1948/GenRad_Experimenter_Oct_1948.pdf

Not bad for a connector designed in 1948!    

It was largely supplanted by the APC-7 connector from Bunker-Ramo which was also a hermaphrodite design but had a 18 Ghz frequency limit

Lots of Tek calibrators used this connector due to its good impedance matching without requiring obsessive connector maintenance as the APC-7 does (cleaning, gauging and finger replacement)





Content by Scott
Typos by Siri
> On May 28, 2017, at 12:21 AM, djl <djl at montana.com> wrote:
> 
> Yep, GR once made the best. The GR connector had at least three things going; as noted hermaphroditic. No need for several sexes. Second, they are seamless 50 ohms, very very small reflections at the connection. Third, banana plugs (also a GR idea, I think) fit in the center "post" of the connector without wrecking anything. GR also made an hermaphroditic connector good to several GHz before passing into legend. . .
> Don
> 
> 
>> On 2017-05-27 05:01, Bob kb8tq wrote:
>> Hi
>>> On May 26, 2017, at 11:21 PM, Gary Woods <garygarlic at earthlink.net> wrote:
>>>> On Mon, 22 May 2017 05:59:59 -0700, you wrote:
>>>> https://goo.gl/photos/tygN5ZFeFLUhc4zX6
>>>> Near Portland Oregon
>>> Neat stuff...did anybody but GR use those hermaphrodite connectors?
>> At one time, GR was pretty much the only source for a wide range of RF
>> and microwave test gear. Anything that was going to work with that gear
>> may have come with the GR connectors. That includes stuff like attenuators,
>> cables, and other bits of “lab clutter”. When you checked the box for the
>> GR connectors, the price went up quite a bit. That made the gizmos with
>> the connectors on them a bit more rare than they otherwise would be.
>> Bob
>>> I have
>>> an adapter for them that came with a wide-band amplifier; "delay line"
>>> type, with a whole row of, I think, 6AK5s in it.
>>> --
>>> Gary Woods AKA K2AHC- PGP key on request, or at home.earthlink.net/~garygarlic
>>> Zone 5/4 in upstate New York, 1420' elevation. NY WO G
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> 
> -- 
> Dr. Don Latham
> PO Box 404, Frenchtown, MT, 59834
> VOX: 406-626-4304
> 
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