Impedance apart, a properly cabled N connector is safer than any PL-259
connector already in the HF spectrum, and should be always used starting
from 50Mhz and above.
N connector withstands current and voltage well over the amateur legal
power, realize better the electrical junction and more important keeps it
inherently protected.
Although the N-connector is not rated for such power levels, I've seen no
damages occurred to one of it (male and female, on antenna side)
with >5Kw RF ( applied for days ), in a 100MHz FM broadcast station.
Incidentally the antenna was damaged and SWR was higher than 1:3.
The troubles with N connectors are generally connected with bad or
improper mountings or by the use of low quality devices.
This also explains why the good adapters are generally so expensive
and why changing from a standard to another in a confortable way
(instead of using the best one) can somethimes lead to have troubles.
73,
Mauri I4JMY
-----Messaggio Originale-----
Da: Tom Rauch <w8ji@contesting.com>
A: <towertalk@contesting.com>; <bgkurz@epix.net>
Data invio: venerdì 6 agosto 1999 17.27
Oggetto: Re: [TowerTalk] F12 C3E adventure
>
> > >3:1 SWR everywhere on all bands! I was sick.... Through some testing
> > and checking we found that the N to SO-239 adapter on the tower had gone
> > bad? It connected my 9913 run up the tower to a 9913 flexi jumper. Why,
> > who knows. Things got better but still very poor....
>
> N connectors are major sources of headaches. They are poor at
> handling high power, especially if SWR is high. They are difficult to
> install.
>
> N connectors belong in the world above 200 MHz unless you have
> an extremely SWR critical system, like video or impedance
> measurements.
>
>
> 73, Tom W8JI
> w8ji@contesting.com
>
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