On Thu, 20 Nov 2003 15:26:46 -0000, "Carl R. Stevenson"
wrote:

I also have serious doubts about the screw-on BNCs for anything but low
power
and low frequency - they may work moderately well for video, but I wouldn't
trust them for RF either.


Hi Carl,

I've measured the properties of BNC/RG-58 out into the GHz and aside
from loss (easily referenced by numerous sources), there are no
surprises. If you trust them for Video, that makes them premium
choices as Video is far more demanding than RF (at least into the HF).
However, as terms, Video and RF are hardly distinctive except that
Video describes an implicit bandwidth and modulation (which
encompasses much of the HF) which is, of necessity, RF.

So, the choice is: do you use BNC for 100KHz-12MHz Video; or do you
use BNC for 100KHz - 1GHz RF? People only abandon BNC for small
geometry considerations: components too close together for breakdown
at high power at high frequency or too small for the currents
involved. Actually, most of those arguments are cable based. In
other words, if you don't trust BNC for any of a variety of reasons,
you are actually arguing against the use of the associated cable it
comfortably mates to. SO/PL are larger dimensionally, but beyond VHF
they are definitely inferior to the smaller BNC.

73's
Richard Clark, KB7QHC