>Yes, that's right - - RG-88 A/U. I got about 130 feet of it as a gift, and
>it looks pretty interesting because it is a tripple braided 52 ohm coax.
My ITT handbook, 5th edition sez: (p.22-38)
Medium size multishielded high-voltage cable. Z=48 ohms.
4 braids
inner conductor 19 - 11.7mil tinned copper
dielectric diameter 0.288 in.
outside diameter 0.515 in.
50.0 pf/ft
max operating voltage 10,000 vrms
Dielectric material: layer of conducting rubber plus two layers of
synthetic rubber
Jacket: noncontaminating synthetic resin
50 pf/ft for 48 ohms implies a pretty high velocity factor. This is about
twice the pf/ft for regular polyethelyne 50 ohm coax: 26 pf/ft and 66%
velocity factor. Velocity factor goes as one over the square root of the
dielectric constant, and capacitance goes directly with the dielectric
constant. The velocity factor should measure around 47%.
No attenuation information given. So, measure it, put connections on each
end and measure the attenuation, like Ed suggested. And, keep us posted
:-)
Kent Torell torell@sicom.com 602-483-2867 x230
SICOM 7585 E. Redfield, #202 Scottsdale, AZ 85260
AB7OA qrp-l 57 ARCI 9075 DM33xn 33.55 N 111.078 W
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