[TowerTalk] N connector, Re: UHF (PL259) soldered center

[Jim Thomson]

Date: Thu, 28 Jun 2018 09:29:37 -0400
From: "john at kk9a.com" <john at kk9a.com>
To: towertalk at contesting.com
Subject: Re: [TowerTalk] N connector, Re: UHF (PL259) soldered center
with braid

<A 7-16 DIN also uses a flat step on the pin for the center connection. 
<The pin is mostly tapered.

<The N HF power rating is more than sufficient for amateur radio. How much
<contact surface is on your antenna and amplifier relays?

<John  KK9A

##  To add to the  connector confusion, they also make a 10-32 connector....and also a 13-30 connector...
and an even bigger  25-80  connector. 

## years ago, when I looked at all this,  Andrew had discontinued making a UHF male for .875 heliax. 
The only thing available was the type N....and the 7-16 DIN......pick one.      Ditto with  LMR-1200DB. 

##  I also looked at LC connectors, and also C connectors.   LC  connectors are out of vouge.  They came in
2 types, 50 ohm, and 52 ohm.  The solid center conductor of the  52 ohm  RG-17 was the pin.  Ditto with the 
solid center conductor of the 50 ohm RG-218 and RG-219.     LC connectors, chassis females, right angle connectors
are huge things, too big, too expensive.   I don’t believe you can even get LC connectors for heliax anymore. The 
50 and 52 ohm connectors are not compatible either. The larger  center conductor diam of the 50 ohm  RG218 and 
double shielded RG219 has to have its solid copper center conductor filed down to fit the older, smaller diam  52 ohm 
chassis connectors. RG-17 makes a sloppy fit on  newer 50 ohm connectors.   Beware when buying surplus.

##  Having had various issues with type N previously on  213 cable,   I opted to swap everything to the 
7-16 Din.   The 7-16 din chassis  female is hardly any bigger than a SO-239 or  Type N.   Its  relatively cheap,
handles loads of current, and has a high  peak V  stand off rating.   I have seen  20 kw  stuffed through the 7-16 Din
on  2-30 mhz, with no issues.    They also make  7-16 female chassis connectors.. with smaller back end square flange.... to mate to 
the  4 x holes of either a type N  or a SO-239 connector. 

##  Im not a vhf or uhf guy, but  I would be  bit leery  about running 2.5 kw into  a 50 mhz, 144 mhz, 220 mhz, or  440 mhz array,
using Type N connectors.   Toss in some swr, and things get dicey. 
Legal limit in canada is  2250 watts pep out on ssb.  750 w with cxr modes like  cw, fm, rtty.  750 watts
cxr on AM..and 3000-3750 pep output on AM.    And all of that is measured at the feedpoint, not the back of the amp.   Typ  I need at least
2.5 kw from any amp..just to get 2250 w at the ant feed point....assuming 10%  feedline and  connector loss.  10% is like .5 db loss.  
7-16 connectors are now readily available on the surplus market.

Jim   VE7RF