Steve Gehring, KL7DC wrote:
>
>
Tom wrote:
>>The N connector models handle less power than standard UHF connector
>>models, and the standard cheap SO-239's on the RCS-8V should still be good
>>for 5 kW if the load SWR is fairly good.
>Why would UHF connectors handle high power better than N style connectors
>in your RCS-8 series coax switch? Comparing the data I have from Amphenol
>on their UHF and N connectors, this might seem otherwise for their
>"standard" models. The voltage rating for the N is far greater, and I'd
>like to think both connectors can intermittently handle 10 amps or less of
>RF at the 5 KW level or below.
>
>"UHF" Connectors: rated for 500 V Pk and DC to 300 MHz with their phenolic
>model
>vs.
>"N" Connectors: rated for 1,500 V Pk and DC to 11 GHz for their TFE model
>
>Has your experience at these power levels shown otherwise?
This topic was discussed on the AMPS list quite recently.
In practice, N connectors are *current* limited. Their center pin is
quite small, basically similar to a BNC. They will handle several
amperes of RF if they're correctly assembled; but if there's any slight
problem in assembly, or if the inner pin pulls back over time, they can
easily arc and burn out.
With 600W on 432MHz I've welded the inner pins of an N connector
together and fried the Teflon insulation... more than once
If you don't need the better VSWR of the N connector at VHF+, the
PL259/SO239 has far better current handling capability and tolerance of
misalignment.
Regarding voltage, it's unfair to compare N connectors (which are always
Teflon insulated) against phenolic 259/239s. Quality Teflon-insulated
connectors will handle any voltage that the cable can.
73 from Ian G3SEK Editor, 'The VHF/UHF DX Book'
'In Practice' columnist for RadCom (RSGB)
http://www.ifwtech.demon.co.uk/g3sek
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