>"Not to be outdone, the television industry has responded with its own bad
>standard, the type F coax "connector," which uses the unsupported inner wire
>of the coax as the pin of the male plug, and a shoddy arrangement to mate the
>shield."
Since the time of Horowitz's first print edition, the F type connector has
evolved into a very reliable small-signal RF connector. The mating inner
connection has improved into a concentric fit around the coax inner conductor.
Back in the '70s, the inner connection typically relied on two small parallel
metallic sleeves. Shield connections were accomplished with a poor-fitting
ring that was often clamped with slip-joint pliers. That's the "shoddy
arrangement to mate the shield' discussed by Horowitz. Integrated-boot
weatherproofing, use of gelled cables, and compression installation tools have
all helped too.
I'm mostly neutral toward RCA phono jacks. Heathkit used an RCA phono jack on
the back of the HW-101 transceiver to deliver 100W into an antenna. After
building one in high school, I recall my friends poking fun at it -- and also
when I built a Heath SB-230 that used a phono jack on the RF input when a BNC
would have probably been a better choice. Provided the phono jack uses a
ceramic insulator, and apart from potential cracking over time, I don't see
much of an issue although I've never seen an RF-grade phono plug. I think
plugs with a phenolic insulator are all I've used.
Even with the XLR-type connector, there's no guarantee that Pin 1 will mate
before pins 2 and 3 100% of the time. Yes, very close in time, but it's still
possible for Pin1 to mate last unless Pin 1 is bonded to the XLR plug shell AND
it's mated with a bonded jack. Most preassembled XLR cables I've seen do not
bond Pin 1 to the shell. 1/4" and 3.5 mm are poor designs as the signal pins
typically rely on a single-point of contact. They also don't guarantee a
shield before signal connection.
Paul, W9AC
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