Bob Nielsen wrote:
>>> I used rotary joints for many years when I was working on antenna
>>> ranges, but don't recall ever seeing any coaxial models with which I
>>> would feel comfortable running amateur legal limit power levels.
>>
>> The one I have here, a 2 channel unit, is apparently rated at more
>> than a
>> kW. I don't know what the limiting component is (is it HV
>> breakdown or
>> thermal dissipation).
>
>I have mainly used single channel (N or SMA connector) types and recall
>that the N units would handle >1 kW peak, but only ~100 W or less avg,
Practical experience of moonbouncers and others is that N connectors
will typically handle 700-800W continuous at 432MHz, or 1.5kW if they're
absolutely perfect. At lower frequencies, the reliable power handling
capabilities are much greater.
G3LTF and others have used N connectors as rotary joints at the 700-800W
level on 432MHz for a very long time. The ring on the plug is slightly
slackened to allow rotation, and then pinned to the plug body with a
grub screw.
If doing it all again today, I would definitely use 7/16 DIN. They got
so many things right with that connector.
--
73 from Ian G/GM3SEK 'In Practice' columnist for RadCom (RSGB)
http://www.ifwtech.co.uk/g3sek
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