When I worked in the CATV world a few years back, we had some type
N (75 ohm) to F connectors that worked very well passed 1 GHz (24 dB
return loss on an HP8753C with 75 ohm test set). These were made either
by Gilbert Engineering or Huber and Shuner (I don't recall for sure). The
main problem with the F is the female connector. The big spring clutch
used in many female F connectors to receive the male pin looks very reflective
at frequencies above 500 MHz. The N-to-F adapters we had used a bifurcated
receptacle on the female side which presented less of a physical discontiunuity
than did the standard clutch and hence had better return loss in the UHF.
Nevertheless the $1 passives our company sold worked reasonably well at
1 GHz (>15 dB return loss and <1.2 dB splitting loss, >22 dB port-to-port
isolation) even with the bigger clutches.
Many of the CATV installations I have seen lately use a two-piece connector
that has an O-ring seal and a plastic snap-in backshell. In fact there is one
on my cable modem that is made by LRC. If I ever get around to it, I am going
to buy a bunch of these and recable my house. I want to get rid of all those
cheap hex style crimp connectors that are about to pull off the coax. Mount
Wilson with all of the LA Basin's TV transmitter is just a few miles line of
sight
from here, so co-channel interference on my cable TV connection is a real
problem with all the cheap cables and connectors that are running underneath
the house.
73 de Mike, W4EF.............
----- Original Message -----
From: "alsopb" <alsopb@gloryroad.net>
To: <Towertalk@contesting.com>
Sent: Thursday, August 09, 2001 5:05 AM
Subject: [TowerTalk] F connectors et al
>
> Guys,
>
> Thanks for all your input. Have found some sources for what I need.
>
> I have really grown to hate type F connectors as much as I hate crimp
> connectors.
>
> 73 de Brian/K3KO
>
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> -----
> FAQ on WWW: http://www.contesting.com/FAQ/towertalk
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> Problems: owner-towertalk@contesting.com
>
List Sponsored by AN Wireless: AN Wireless handles Rohn tower systems,
Trylon Titan towers, coax, hardline and more. Also check out our self
supporting towers up to 96 feet for under $1500!! http://www.anwireless.com
-----
FAQ on WWW: http://www.contesting.com/FAQ/towertalk
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