I came across a spool of some very small coax in the hopes that it could be
used in 802.11 but now not a clue of what it is. It is on a Raychem reel.
The Description tag says 5028A1318-0 440086. As best I can measure it is
0.075 inch OD, 0.055 braid diameter, 0.040 insulation OD and the center
conductor measures 0.015. The outer jacket is black and the inner
insulation is tan in color. The braid is very dense fine wire as is the
center conductor. It looks and feels like high quality stuff. Any help or
even a good guess appreciated.

a quick visit to raychem.com finds this:
http://catalog.tycoelectronics.com/T...18-0&LG=1&I=13


"edard" wrote in message
...
I came across a spool of some very small coax in the hopes that it could be
used in 802.11 but now not a clue of what it is. It is on a Raychem reel.
The Description tag says 5028A1318-0 440086. As best I can measure it is
0.075 inch OD, 0.055 braid diameter, 0.040 insulation OD and the center
conductor measures 0.015. The outer jacket is black and the inner
insulation is tan in color. The braid is very dense fine wire as is the
center conductor. It looks and feels like high quality stuff. Any help
or
even a good guess appreciated.

Dave wrote:

a quick visit to raychem.com finds this:

http://catalog.tycoelectronics.com/T...18-0&LG=1&I=13


Wow Dave thanks. Who would have thought of trying Raychem? Duhhh

This sounds similar to some cable I got surplus a number of years ago.
The loss was surprisingly high at 7 MHz. I'm quite sure the reason is
that the center conductor is made from several strands of very fine
copper-clad steel wire. Although the copper is probably a sizeable
fraction of the overall wire thickness, it's still thin in terms of skin
depth at the lower part of the HF region because of the very small
strand diameter. Consequently, significant current flows in the steel,
which is very much more resistive than copper at HF. Loss at VHF is
about what you'd expect from a copper center wire.

So I recommend checking the loss before using the cable at HF if loss
might be important to the application. I used it as low-weight feedline
for Field Day (I generally backpack my FD gear), and was prepared to
accept the loss I thought it would have as a trade for the low weight.
But I found the loss to be considerably greater than expected.

Roy Lewallen, W7EL

he mentioned use for 802.11 so low freq stuff shouldn't be a problem.

"Roy Lewallen" wrote in message
...
This sounds similar to some cable I got surplus a number of years ago. The
loss was surprisingly high at 7 MHz. I'm quite sure the reason is that the
center conductor is made from several strands of very fine copper-clad
steel wire. Although the copper is probably a sizeable fraction of the
overall wire thickness, it's still thin in terms of skin depth at the
lower part of the HF region because of the very small strand diameter.
Consequently, significant current flows in the steel, which is very much
more resistive than copper at HF. Loss at VHF is about what you'd expect
from a copper center wire.

So I recommend checking the loss before using the cable at HF if loss
might be important to the application. I used it as low-weight feedline
for Field Day (I generally backpack my FD gear), and was prepared to
accept the loss I thought it would have as a trade for the low weight. But
I found the loss to be considerably greater than expected.

Roy Lewallen, W7EL

Hey, that stuff might be great to use as an attenuator between an HF
radio and a transverter...hmmm....

Scott
N0EDV

Roy Lewallen wrote:

This sounds similar to some cable I got surplus a number of years ago.
The loss was surprisingly high at 7 MHz. I'm quite sure the reason is
that the center conductor is made from several strands of very fine
copper-clad steel wire. Although the copper is probably a sizeable
fraction of the overall wire thickness, it's still thin in terms of skin
depth at the lower part of the HF region because of the very small
strand diameter. Consequently, significant current flows in the steel,
which is very much more resistive than copper at HF. Loss at VHF is
about what you'd expect from a copper center wire.

So I recommend checking the loss before using the cable at HF if loss
might be important to the application. I used it as low-weight feedline
for Field Day (I generally backpack my FD gear), and was prepared to
accept the loss I thought it would have as a trade for the low weight.
But I found the loss to be considerably greater than expected.

Roy Lewallen, W7EL