[RFI] Weird RFI Episode

[Jim Brown]

On 9/25/2023 2:10 AM, Jack Ference wrote:
> You must always “Frank” all PL-259 connectors using a small wrench to complete the physical and electrical connection.

And Frank emphasizes, as do I, that all connectors, including barrels 
and adapters, must be first quality. For me, that means Amphenol 83-!SP 
for cable-mount males, and comparable adapters; in the case of adapters, 
stamped MIL-spec used/surplus parts that I buy at ham flea markets. I'm 
not familiar with qualifications of components in parts of the world 
other than North America.

While there may be decent parts by other vendors sold as OEM parts to 
mfrs, some of which have the capabilities to QC them, I have learned not 
to trust anything but Amphenol and MIL stuff. If it isn't that 
top-quality Amphenol or MIL, I consider it JUNK.

When getting back on the air in 2003, I built a parts stash of various 
adapters from hamfest vendors, including those who advertise in QST. 
Over 5-10 years, those parts caused me all sorts of grief. Tees and 
elbows had tiny wire springs rather than the solid centers of real 
adapters; I had one melt during a contest. Others generated 
intermittents that were a pain to troubleshoot. A three-way female tee, 
supplied by a mfr of a VHF antenna, fell apart mechanically!

And don't get me going on the glorified zip-cord sold for power and 
speakers, which has super-thick insulation but with copper that's much 
smaller than the advertised gauge. AND the zip cord is LOUSY for RFI; 
ALL power and audio cables should be TWISTED PAIR, which strongly 
resists RFI, HUM, and NOISE, while zip cord does NOT! Cables for ALL 
such installations should be twisted pair, including those when they 
carry PULSED DC for applications like solar systems, where the charge 
current PULSE-MODULATED DC rectangular waves; that content is DC plus a 
VERY strong broadband RF component. The same is true of what goes into 
and comes out of CD-AC inverters. BTW -- the ARRL book on alternative 
power is a train wreck about this stuff!

This reflector is about RFI, so I'm going into the weeds, which is where 
the bodies are buried!

73, Jim K9YC