Let’s take a good look at how connections are made using PL-259 connectors. For
RG-213 size coax, the center conductor goes straight through the coax
dielectric and into the center tube of the connector where it is soldered. The
shield is cut back so that it does not contact the center conductor, the
outside of the shield is then soldered to the inside of the PL-259 shell. The
inside of the shield is not connected to anything, but relies on solder to
connect it to the connector shield. Thus either there is no connection from the
inside of the shield, where the signal is carried, to the shell and only the
outer shield connects, or the two combine at the connector.
Now let’s look at the coax that was used in the choke tests. I believe these
also used PL-259s with the UG-175 adapter. The center conductor is handled the
same way as in the RG-213 case. There is a big difference in how the shield is
handled. In this case the braid is frayed, then folded back onto the UG-175. At
this point the frayed shield is soldered to the shell of the PL-259 and to the
UG-175. Because of the fraying, we don’t know whether the inside or outside of
the shield connects, and most likely it is a combination of the two. In other
words, the two skin effect currents are again combined at the connector.
Connectors are very important in this system. They must be added to the
analysis. Without them, we have to question the validity of the tests.
Did you think that re-radiation was the mechanism for the outer currents to
cause problems in your system?
73,
Jack, W6FB
> On Sep 30, 2025, at 11:22 PM, Jim Brown <jim@audiosystemsgroup.com> wrote:
>
> On 9/30/2025 2:29 PM, Jack Brindle via TowerTalk wrote:
>> No. All connectors that connect the inner and outer edges of the shield.
>> Purely from skin effect.
>
> I don't buy any of this, Jack. The shells and center conductors of connectors
> splicing two sections of line exhibit skin effect just like any other
> conductor. The only difference are the dimension of the shield as it goes
> through the connector(s).
>
> 73, Jim K9YC
>
>
>
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