You are right Bill, no HF data at all.
It pays to understand what you are reading.
As I said in an earlier post, using UHF to N adaptors can also cause
problems with mismatch. A lot of those adaptors are much worse than plain
old PL259 plugs by themselves.
Even the data that is given for VHF and UHF can be misleading. If one is
measuring insertion loss you have to be careful.
Is it really insertion loss or apparent loss due to mismatch of impedance.
If you were to place your bird wattmeter in line with PL type adaptors you
see what looks like insertion loss in a fixed 50 ohm system. But the kicker
is that with a fixed 50 ohm system the generator is not seeing the same load
as it did before and its output is changed. If you have a matching device to
retune so that the generator sees a 50 ohm load again, that apparent
insertion loss all but goes away.
You do not get a 1 db insertion loss at 450 MHz with a PL type connector.
True it presents a slight mismatch but if that is compensated for the true
loss is very low.
We do this compensation all the time by retuning our transmitter or antenna
tuner.
If the PL connector had that much loss Motorola and many other 2 way radio
manufacturers would have done away with it long ago at VHF and UHF. They
used them on all those radios.
At HF it is a non issue.
73
Gary K4FMX
> -----Original Message-----
> From: towertalk-bounces@contesting.com [mailto:towertalk-
> bounces@contesting.com] On Behalf Of Bill Aycock
> Sent: Tuesday, April 13, 2010 10:21 PM
> To: Tower and HF antenna construction topics.
> Subject: Re: [TowerTalk] N or PL259
>
> Thanks much, Randy. It is as I thought, no HF data at all.
> The work seems to be fairly well done, but I will need to translate it
> to
> losses I am more concerned with, and look for pertinent HF data.
> Bill--W4BSG
>
> ----- Original Message -----
> From: "Randy Lake" <randyn1kwf@gmail.com>
> To: "Tower and HF antenna construction topics."
> <towertalk@contesting.com>
> Sent: Tuesday, April 13, 2010 8:29 PM
> Subject: Re: [TowerTalk] N or PL259
>
>
> > http://www.scribd.com/doc/24284391/PL259-Connectors-vs-N
> >
> > On Tue, Apr 13, 2010 at 9:20 PM, Bill Aycock
> > <billaycock@centurytel.net>wrote:
> >
> >> What Frequency range did the VK3JEG article cover? I agree with Jim.
> I
> >> have
> >> seen lots of data that cannot justify N's for LF, MF, or HF. Lots
> shows
> >> it's
> >> ??? at vhf, but probably justified at UHF. where was the VK3 data
> >> published?
> >> Not an expert, by any stretch. Bill--W4BSG
> >> ----- Original Message -----
> >> From: "Martin Staffa" <geitaemort@sbcglobal.net>
> >> To: <TowerTalk@contesting.com>
> >> Sent: Tuesday, April 13, 2010 4:23 PM
> >> Subject: [TowerTalk] N or PL259
> >>
> >>
> >> >I take my information from many articles that I have read.the
> obvious
> >> >choice for me was the N connectors, I am not a genius so making the
> >> >right
> >> >decision depends on comparing studies of people that are a lot more
> >> >intelligent than myself, again not a genius. I would direct a very
> good
> >> >article by the author Chris J. Arthur VK3JEG and this is what I have
> >> >based
> >> >my decision on. Martin P. Staffa N1KGP
> >> > _______________________________________________
> >> >
> >> >
> >> >
> >> > _______________________________________________
> >> > TowerTalk mailing list
> >> > TowerTalk@contesting.com
> >> > http://lists.contesting.com/mailman/listinfo/towertalk
> >> >
> >> >
> >>
> >>
> >> _______________________________________________
> >>
> >>
> >>
> >> _______________________________________________
> >> TowerTalk mailing list
> >> TowerTalk@contesting.com
> >> http://lists.contesting.com/mailman/listinfo/towertalk
> >>
> >
> >
> >
> > --
> > Randy Lake N1KWF
> > 73 Gunn Rd.
> > Keene,NH
> > _______________________________________________
> >
> >
> >
> > _______________________________________________
> > TowerTalk mailing list
> > TowerTalk@contesting.com
> > http://lists.contesting.com/mailman/listinfo/towertalk
> >
> >
>
>
> _______________________________________________
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