On Feb 25, 12:12*pm, Owen Duffy wrote:
K7ITM wrote :

...

In any event, it seems a reasonable way to get a large diameter RF
conductor that remains flexible...I'd be very surprised if...

Tom,

I have attempted to predict the behaviour of bootstrap coax traps, and an
important factor is the effective RF resistance of the outside of the coax
which forms an inductor.

My measurement capacity is quite limited.

Trying to reconcile my prediction with W8JI's measurements of such traps
makes me think that the effective RF resistance is much poorer than a tube
of the same size. Factors causing this would be braiding, proximity effect
and dielectric losses in PVC jacket.

Owen

I think I'll be in good agreement with you, here, Owen, by saying that
the right way to find out about something like this is to actually
make some measurements on the configuration in question. Maybe I can
come up with something... I do have reasonable measurement technology
available, though getting it "right" isn't trivial, especially with
balanced open-wire line. I do have some ideas and if I can find time
will try a couple different ways to see if they agree. Time, right
now, will be the problem.

Cheers,
Tom