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RE: Feed line help



Your question has several parts.  Here is what I know about the feedline:

1. The term "flooded" has to do with how the foam dielectric is made.  For a
cable to be rated as direct burial it needs to be both flooded and
polyethylene jacketed.  If it is flooded with a PVC jacket, it is suitable
for weather resistant service.  A non-flooded cable tends to wick up water
when outside.
2. RG-6 is a 75 ohm cable.  Most of your amateur equipment and connectors
are 50 ohm.  This impedance mismatch can be either trivial or very serious
depending on what you are trying to do.  I forget the exact SWR that
results, but I think it was in the 1.2 or 1.5 range.  If you are using the
cable for receive only, it is fine.  Transmitting is more problematic.
3. 15 cents is about right for a good wholesale price if it is dual.  For
single it is a bit high.  I think I paid about 16 cents for the last spool
of dual I bought and something like 6.9 cents for the single (inclusive of
shipping to the Houston area - wholesale only).
4. It works superbly for VHF and UHF receive cable from the Antenna to the
shack/house.  Far better than the standard RG-59 that you get at RS (or
equiv.).  It has much less "tilt" - a condition where the channels on the
upper UHF get to the receiver with much more loss than the low VHF (for
example channel 2 vs. channel 67).  Also in that range other receive uses
are scanner antennas, EMWIN weather data, NOAA weather data, "low band" ATV,
Aircraft, public service, etc.
5. It works very well for low microwave systems (1 GHz to 2 GHz) where you
have a preamp at the antenna.  For example, remote GPS antenna's (watch out
for timing errors though),  GEOS receivers, ATV, and DSS, C, & Ku band
receivers.
6. It is overkill, but cheap for receive feedline from SWL dipoles, slopers,
etc.  and it is nice in that the PE jacket flooded conductor stuff can be
direct buried and then mowed over easily so your antenna farm doesn't have
to be hand edged.
7. Another source of, usually free, 75 ohm low loss cable is your friendly
cable installer.  They often have roll ends of aluminum jacket 0.5 inch
hardline that they will give you.  All of the above applies to it as well.
If you need to know how to solder to the aluminum or to adapt an N connector
to it, just let me know.

Basically I use it for just about any general receive only use.  I try to
transmit through good "high dollar" 50 ohm cable though.  Good cable is
almost always cheaper than buying more watts.  Hope this helps point you in
the right direction.

Ron

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