Date: Sun, 15 Jan 2012 18:13:34 -0500
From: "Paul Christensen" <w9ac@arrl.net>
Subject: Re: [TowerTalk] PL259 Insertion Loss?
> With this setup, I could measure no significant losses. I am convinced
> (I convinced myself) that the "UHF connector loss" is a myth, right up
> there with that myth about the superiority of N-type at HF.
The connector quality issue probably boils down to reliability and cost.
However, in instances where the connectors are being used to accurately
measure impedance and return-loss (e.g., VNA loads) then better connectors
are needed as F increases. For HF S11 reflection measurements into most
line and antenna applications, it's probably a non-issue.
Just yesterday, I was bashing the Asian BNCs. Not that I've changed my
position, but even when a connector is so bad that return loss accuracy
shifts from 70 dB to 25 dB, the final results are still fine for most
antenna measurements. But that amount of degradation tells me that if QC
was poor at the time of manufacture, perhaps it's not a connector/adapter I
want to use when I need it most.
Paul, W9AC
## I have used the all silver plated/Teflon van Gordon PL-259's with zero
problems. It's
about the only thing they make that actually works. The Amphenol PL-259's that
are nickel plated
are no fun to solder. The silver/Teflon types are the fastest/easiest to
install. Nickel plated connector's
are a pita. I use my 100 w american beauty soldering iron on all of this
stuff. it has a huge 3/8" diam
tip. You can also get those irons in 560 w variety..with 1/2" tips [used
for plumbing]
## Ok, Andrew stopped making UHF connector's for 7/8" heliax back in the
mid 90's. That only leaves
2 x options.... type N and 7-16 DIN. The 7-16 din is the same price, or
slightly more vs the type N..and is the
real deal. I'm done with type N these days. I went on this type N
conversion program back in the 80's..and it was
a waste of time and effort. Good quality silver/Teflon uhf connectors are
plenty good enough for 213 u..and around the
shack. But the output connectors on all my hb amps are 7-16 Din..and ditto
with wattmeter couplers, baluns, remote
switch box's etc. Constant Z, zero loss, huge V break down rating, and massive
center pin. The chassis female 7-16 din
is only 1.25" square..which is not much bigger than the 1" square uhf/type N
types. IMO, it's pointless installing a Type N
onto the end of LMR-1200DB/heliax/etc. The center pin on any type N is the
same size as the bnc connector on your
2 m FM rubber duck ant. 7-16's are good up to 6 ghz... and they are now
showing up on the surplus market. With a
4 kv peak break down, they do the job.
later... Jim VE7RF
ant.
all of it outside.
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