K7ITM wrote in
:

....
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