G5RV Wire.

iTom

Hi all I have just bought a Icom 7000 and I would like and info on how to put up a G5RV WIRE,I am going for my licence in a few months and would like to learn and pick up a few tips from this radio before I do my test.

Tom....

watty

A G5RV is a compromise version of a dipole for 80m to allow it to work multi-band up to 10m. The feed is an integral feature of the inverted V designed for very little space.

If you have 20m+ of distance free in ANY direction from where you can have the radio, then an end fed wire aerial costing under €5 can be better. If you have 40m of space, then a regular dipole (can be done under €10) outperforms a G5RV.

If the aerial system has not got the height and length of special matched feeder, it's just a dipole (invered V or not), not a G5RV

See
Origin G5RV concept. The Inverted V version is a later idea to save more space.
http://www.qsl.net/aa3px/g5rv.htm

See also
http://sharon.esrac.ele.tue.nl/~on9cvd/E_G5RV%20als%20breedband%20antenne.htm

DO NOT buy a G5RV in a packet. These usually are simply overpriced dipoles with a balun or simply a 4:1 impedance (2:1 windings) transformer for coax in the middle.

Lots of people put up an inverted V and call it a G5RV. Unless it has a specific length of feed that is part of the aerial, it's just a modified dilole, not a G5RV. If you have a single high point above the "radio shack" and limited space, you may need an inverted V rather than a G5RV.

In any case the 2:1 ratio (4:1 impedance) matching coil is easily wound air core on a 1.5" piece of plastic pipe using 20 turns mains flex to the dipole arms (say the blue core) 10 turns mains flex (say the brown wire) on top connected to coax (keep insulation on and wind tight. Optionally wind the coax around an old TV LOPT core, PC SMPSU core or ferrite rod as a current balun. RG58 coax is sufficient. You only need RG213 for VHF or several kW of HF.

http://www.hamuniverse.com/dipivcal.html

http://www.k7mem.150m.com/Electronic_Notebook/antennas/inverted_vee.html

http://www.geocities.com/Augusta/7117/antenna.html


You may also need an ATU/Match unit.

For 60m to 6m a bicubical aerial may be a good space saving alternative and needs no tuning or matching.

iTom

Thank you Watty,

I all ready bought a G5rv from SEC.ie ah few months ago as he said it would be the best for someone with very little space.

All this is new to me but I am getting to terms with it.

Thanks again for all your help and will keep you posted on how things are going.


Tom....