Excess coax-- what do you do with it...?
I am looking for advise on what to do with excessive coax. I am remodeling and will be moving my shack 40' from it's current location in a few weeks. I just put up my new antenna's and I don't want to cut my 150' coax. In the mean time, I have a 50' puddle of coax all over the floor. I have searched Excess coax, extra coax and coax in the forums and come up empty, I apologize if I missed a post.
Coax is RG8X
Antenna are G5RV and an Eagle One.
Obviously unused coax adds some loss that isn't doing you any good; however if you don't care about that, why not just neatly coil it up (a good diameter is 18" or so), and tie-wrap the coil so it remains neat? This can reside behind the equipment in the shack, or outside where you don't have to look at it.
If you don't want it on the floor, coil it neatly and hang it on a hook behind the equipment.
Coiling the coax does no harm in any way except to add the loss of the cable used.
look up losses for 150 ft of RG8X
look up losses for 110 ft of RG8X
RG8X is not exactly low loss cable
if you hang out on higher bands
say 10 or 12 meters
cut your losses
if you hang out on lower bands
it does not matter that much
not like RG8X is that expensive
use the extra cable to make up jumper cables
if it was my station
would cut out the excess coax
in a New York min
The G5RV operates the coax with standing waves, and there is benefit in using the shortest coax.
Originally Posted by K4NOG
Do you use the Eagle One with an ATU at the base, say an AH4, SGC237 etc, or do you use their 4:1 balun idea?
Yes Trish, that is usually wrong.
Originally Posted by G8DZC
Increasing the length of the line increases line loss, and it does decrease the VSWR looking into the line, but in most cases it will result in less radiated power.
In some unusual cases, the lower VSWR might just result in higher transmitter output power that more than offsets the increased line loss, but it is unlikely.
WB2WIK is correct that it can be coiled up and stashed behind the desk but given the fact that it is RG8X and most RG8X coax is not premium quality anyway, if it were me, I'd cut the excess off and use it for jumpers, etc. Of course if it were me, I would not be using RG8X anyway, but then that's just me.
A true G5RV design is optimized for 20M and has to be matched on other bands so there is already losses from that so by limiting the coax length, you'll help reduce losses in both RX and TX.
Just my $0.02 worth.
A big coil of coax is not a good idea. It is not going to help any thing. The losses during TX do not make it to the antenna but can cause rf problems in the aria every thing from interference with other electronics to rf burns from metallic objects. On the receive end you just lose signal strength. Coax ends are cheap.
Coil it up outside just before it gets into the house, unless you never ever will need it that long ever again.
Originally Posted by K4NOG
If you are sure that is where stuff is going to stay, shorten it.
As Owen says...with a G5RV you want the cable as short as possible while still having a nice routing.
If a pretty permanent antenna and coax run, I cut it to length. If something kinda temporary and subject to change, I try to leave the excess (unless the excess is excessive ) coiled up outside by where my cables enter the house.