Short Takes #26: Cables, Coax, Connectors and Kooks

Hmm, your glowing paean to M&P cable makes me think of fat audio cables.
For instance, their Ultraflex 13 claims -2dB loss per 100 meters at 50MC in a flexible cable
1/2" Hardline has the exact same loss
My baloney meter is twitching
The center dielectric in their line of cables is the exact same polyethylene used by every other manufacturer.
Their outer foil is copper rather than aluminum used by most - I'll give them a half tenth of a dB advantage for that
The outer braid and fat jacket over the bonded foil has zero effect on loss

I went to order a 100 foot hank with their connectors to run a test with - then I woke up on the floor - I must have bumped my head
Yeah, their cable is good quality
Is it worth 200% to 300% over the well known brands of half inch (nominal) RG/LMR cables
Ya gotta remember, ordering over there you are paying the socialism tax

 

Thanks for the post, Doc. My glowing review is because I've had nothing but great experience with their cables and connectors. I'll pay extra not to have to worry about something -- y0u may not have the same feeling. Their PL-259 equivalent, for example, is superb. You don't have to order from Italy, as it's sold via one of the big USA dealers (I believe Gigaparts or HRO). Dave

 

I have miles of feed lines.
Consisting of open wire balance ladder feeds 300 ohms to 900 ohms, 50 ohm hard-lines 1 5/8", 7/8" & 1/2" , 50 ohm coax (LMR 400/600), 72 ohm Hard-lines 7/8", 3/4/", & 1/2", RG11 with a 12 gauge steel messenger cable for overhead, RG6 for receive antennas (all 72 ohm) along with hundreds of jumper coax cables.

See
https://www.k0uo.com/post/feed-line-systems

 

Mine is more modest. One 127' base insulated tower, supporting a 137' long doublet attached to the tower at the 119' level drooping to 100' high at each end, fed with home-made 450Ω open wire line (#10 wires spaced 2" apart), extending down through the interior of the tower with spacers holding it at the geometric centre of the triangle. The doublet is usable on 160-10m, with separate balanced link-coupled tuners for each band located in a hut at the base of the tower, remotely tunable from the shack. The tower also serves as a quarter-wave vertical tee on 160m, working against about 3 miles of buried copper wire radials. The doublet serves as the horizontal portion of the tee.

The 140' run between shack and tower consists of another home-made open wire line (#8 wires spaced 2.5" apart) held 8' off the ground with steel poles, cross-arms and stand-off insulators. Additional balanced tuners in the shack match each of the transmitters to the 450Ω OWL.

The OWL between shack and tower operates as a matched (un-tuned) transmission line with negligible standand waves, while the OWL going up the tower serves as a tuned feed line (operating with standing waves).

Not a sprig of coax anywhere in my entire transmitting antenna system.

 

Thanks for the post Don. Really wish I had that kind of setup, Dave W7DGJ

 

We coaxed ourselves to use coax after -- Guess Who? -- came up with an inexpensive way to extrude plastic dielectrics c. 1944...and the Guess Who was American Phenolic (now called Amphenol).

I coaxed myself to using coax all over the place up through the lower microwaves, where waveguide takes over above that.

Coax has so many advantages for RF transmission <5 GHz or so it's impossible to list them all without writing a book. But "new names" with claimed advantages when the materials and dimensions are the same as the old names should be viewed with lots of skepticism.

However, for those who like new stuff, I've invented a unique weight-loss product that is 100% effective, with a money-back guarantee. I call it the "eating less" product...