SOME 'junk' PL259s are fine. If there are problems with the threads you
will know right away. I have had some that are plated with something
that won't take solder, or which have plastic insulation that melts when
you solder the center pin. But again, you will know this right away.
SO239s and barrels may have contact tension problems that take awhile to
manifest themselves. And elbows and Ts can have internal issues (like
the famous elbows with little springs to join the two parts). For these,
only Amphenol or mil-spec will do.
Having said all this, just before I moved here, I ordered a bunch of
Amphenol connectors, including the PL259s.
73,
Vic, 4X6GP
Rehovot, Israel
Formerly K2VCO
http://www.qsl.net/k2vco/
On 11 Oct 2016 11:38, Jim Brown wrote:
On Mon,10/10/2016 4:49 PM, Josh Fiden wrote:
If you're concerned about the additional loss of a barrel connector at
50MHz, you should be using feedline with lower loss than LMR400 up the
tower.
The loss in GOOD quality UHF connectors and barrels at 50 MHz is
negligible. There are urban legends (false, as usual) claiming that
every connector loses a dB. The grain of truth is that JUNK connectors
may introduce significant loss, but GOOD connectors and barrels do NOT.
"Good" means Amphenol 83-1SP for the PL-259s, and Amphenol or surplus
MIL-spec for the barrels.
Several years ago, I made up more than a dozen 100 ft cables using a
cable of somewhat better construction than LMR400 (Commscope 3227) for a
DX trip. The connectors were Amphenol 83-1SP that I soldered myself. To
test those cables, I spliced them together using Amphenol barrels and
measured the loss of about 1300 ft of cable up to 500 MHz using HP
generator and spectrum analyzer. The measured loss was LESS than the
manufacturer's spec. There were 27 83-1SPs and 13 barrels in line.
JUNK connectors are the shiny,unbranded stuff you see at ham flea
markets, and sold online and in ham magazines.
73, Jim K9YC
______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net
This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to arch...@mail-archive.com
