Re: Thoughts on a Ham Bus

Tim Gorman


I think you missed the point. After WWII huge numbers of these
connectors were available because they were made for military use and
it was easy for commercial and private interests to obtain them and use
them. The amateur community is going to have a difficult time
generating a standard that sees widespread acceptance with lots of
availability purely because of limited economic impact.

Any future standard is going to have to also be made in huge numbers as
well. Otherwise it will never become a "standard". The only entity
today that can generate that kind of usage of a standard *will* be
military based.

The only other entity that had that kind of power for setting a
standard was the old Bell System. Look at the RJ-8 and RJ-45 standards
or even the N-connector. They were driven by usage in the telephone
systems. But the Bell System no longer exists and is no longer capable
of driving standards.

I'm not sure what RF connectors you are speaking of but if you go to
the Amphenol site even the SMC connector is based on a mil-spec

The phono connector will work at RF but it has many problems. It is not
a positive mechanical connection and is subject to corrosion affects.

Again, standards become standards because of a lot of use in a lot of
places. You would be better off looking for a standard bus arrangement
by looking at electronic equipment in the military. Those standards see
a lot of usage, they last for a long time, and there are typically
multiple suppliers. I know some of that equipment used plug-in cards
with a backplane.

tim ab0wr

On Thu, 21 Jun 2018 11:32:48 -0700
"Jerry Gaffke via Groups.Io" <> wrote:

Going from "the PL259 somehow got established as a standard in the
ham world 80 years ago" to "any bus standard that succeeds will
likely have originated in some military gear" is quite a leap.
 Nothing much is mil-spec about the uBitx.

There's better choices than the PL259 and/or the BNC for coax these
days. But they got established, and hams are a conservative lot.
For HF QRP , some would argue that an RCA audio connector is a better
choice (I would).

Somewhat related, several in the forum have reported that the BNC
jack supplied with the kit has been machined with less than ideal
tolerances.  If you aren't seeing any power out to your dummy load,
be sure to check that the center pin of your BNC is reliably making
contact, and perhaps spend a few bucks on a better jack.  Something
like Mouser 530-B1094. 

Jerry, KE7ER

On Thu, Jun 21, 2018 at 09:40 am, Tim Gorman wrote:

I think you'll find the so239/pl259 combination as well as the bnc
were first standardized by the military and then the commercial
industry picked them up.

Unless you can find a bus standard that has been adopted by the
military first you probably aren't going to find wide acceptance.

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