>
>on 9/28/01 3:45 AM, Steve Thompson at g8gsq@qsl.net wrote:
>
>> The Suhner catalogue gives a graph.
>>
>> 20MHz 5000W
>> 50MHz 3200
>> 200MHz 1600
>> 1000MHz 750
>> 10000MHz 250
>
>Yikes! 750 Watts into an N at 1 GHz. That's pushing it. In the cellular
>industry the typical max power that is usually talked about for N connectors
>is 500 Watts at 900 MHz. Of course, the H&S figure is into a good load.
>
>Of course the original question was the ratings at HF. At amateur power
>levels, there is absolutely zero problems with either the N or the UHF.
// Water vapour getting into coax fittings is not a problem?
> I would believe the UHF would handle more power because of the large diameter
>center pin (of course the quality of UHF connectors does vary and I would
>assume a UHF with a phenolic dielectric to handle much less power than a UHF
>with a Teflon dielectric).
>
>IMHO, there is really not much advantage to using N connectors at HF.
... provided you don't receive any rain or fog.
Type-C connectors have more current carrying ability and more voltage
withstanding ability than Type-N. Type-C are moisture proof, and bayonet
mount.
>The performance improvement in terms of VSWR and S21 are so minimal as to be
>negligible. N connectors are more expensive and harder to assemble. They
>do have the advantage of being more waterproof than UHF connectors in
>outdoor environments but other than that a UHF is really a better connector.
>I would recommend N connectors at 2 meters and above but even at 2m, the UHF
>is still pretty good. But as the above chart shows, above 200 MHz, legal
>limit ham amps become a problem for N connectors.
>
>A lot of people think that because of their size that N's are inherently
>high power connectors. Well, in reality the male/female interface of an N
>is really identical to that of a BNC connector. Yep, center contacts are
>the same size. The difference is in the outer conductor and contacts. If
>you doubt be try mating a male N to a female BNC. You can do it and the fit
>is pretty good. The geometry of the N's do make their voltage breakdown a
>bit higher than the BNC but not that much.
>
// The pin spacing in an N and a BNC are identical. Both breakdown at
c. 4000v on my hi-pot tester.
>If you really want high power handling, go with a 7/16 DIN. Overkill at HF
>for sure though!
// For tetrodes with handles on the 20m - 10m HF bands, quite probably
not.
cheers, Jon
- R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures.
end
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