> Roger (K8RI) wrote:
>> My problem is neither the loss per connector or number of connectors. It
>> is the breakdown voltage when running QRO into a very high SWR at the
>> band edges on 75 and 160.
>> I standardized on N connectors, but they don't have the voltage ratings
>> to handle that kind of voltage. I see at much as 8:1 at the band edges
>> on 75 and even higher on 160 so I've had to go back to UHF connectors on
>> the HF bands. IT's not a problem or hasn't been on 40 through 10, or
>> 3ven 6-meters...so far. But I need to have higher voltage ratings for
>> at least 160 and 75 and the only way I can see doing that is with true
>> UHF connectors even on LMR-600 even if I have to resort to "Clamp type
> Have you actually had breakdown occur?
> The "databook" ratings for
> connectors are quite a bit less than the actual AC breakdown voltage,
> for a variety of reasons. For instance, PL-259/SO-239 gets used for
> 20kV all the time, although the spacing is wider on that connector,
> particularly across the face. There's also lots of different kinds of
> N, in terms of the dielectric construction.
I've blown out Amphenol, silver plated, double female connectors. It was
the first thing I checked and the last thing I found...not at the same
time. I pulled out the connector and it measured fine with an ohmmeter
but with it in the swr under load was very high. I even removed the
balun. Finally I did what I should have in the first place and tested
that connector by substitution. The new connector worked fine, the old
one was shorted.
I've also blown out a few of the male N-connectors at the antenna.
Running QRO and an SWR on the band edges of 8:1 or greater. 160 is even
worse. I haven't lost a UHF connector yet. OTOH I've misplaced a few.
I've never had a problem with N-connectors on VHF or UHF either, but
there the SWR is usually quite low even on some fairly wide excursions
on 6-meters. 2-meters seems to be capable of covering the CW and FM
portions of the band. On 440 I live too close to Canada so power is not
a problem for the antenna system unless I can get a special issuance for
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