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. 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. 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.
If you really want high power handling, go with a 7/16 DIN. Overkill at HF
for sure though!
73,
Jon
NA9D
-------------------------------------
Jon Ogden
NA9D (ex: KE9NA)
Member: ARRL, AMSAT, DXCC, NRA
http://www.qsl.net/ke9na
"A life lived in fear is a life half lived."
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