[10m] Bob's Antenna Question

[Mike Duke, K5XU]

Bob, here is my two cents.

I have never found a G5RV to be a solid performer on 10 meters. They 
will work, but any number of other antennas, including a simple 10 
meter dipole or quarter wave ground plane 20 feet or so above ground, 
will blow them right off the band, both in overall performance, and 
ease of tuning.

The truth is that any "multi band" antenna will have one or more bands 
where it will work kind of, but not very well.

So, my suggestions are:

1. You said you already have "better" 10 meter antennas. Use them 
rather than the G5RV on 10 meters. If you need the G5RV for 80, 40, 
and 20, run with it. It does okay on 80, and works very well on 40 and 
20, which is where the original inventor wanted it to work in the 
first place.

2. If you need an antenna for 30 meters, and want that antenna to work 
well on other bands above 30 meters, look at the 44 foot center fed 
doublet. Google the phrase "44 foot doublet," or "44 foot dipole," and 
you will learn more about this antenna than you ever wanted to know. 
Basically, it is a 44 foot long dipole that is fed in the center with 
450 Ohm ladder line. While it requires a tuner on all bands, it has 
the radiation pattern of a dipole from 30 through 10 meters. It is 
really an Extended Double Zepp on 10 meters, and has significant gain 
over a dipole. I used this antenna for the first 6 months or so until 
I could get my tri-band beam in the air after moving to my present 
QTH.

One important thing to note is that while the 44 foot doublet can work 
on 40 meters, using it there is really tough on your antenna tuner. 
Some of the 300 watt class tuners will melt down when trying to tune 
the 44 foot doublet on 40 even at a power level of 50 watts or so. The 
same statement holds true when trying to use its 88 foot cousin on 80 
meters. The 88 foot model, much like the G5RV, gets tricky above 20 
meters, so for 30 meters and up, stick with the 44 foot version.

3. If all you really want is an effective wire antenna for 30 meters, 
Try a basic dipole, Delta loop, or half square.

4. If you have the room for it, a full size 80 meter dipole fed with 
450 Ohm ladder line is far superior to the G5RV on 80, and maybe even 
to a lesser degree on 40, depending on whose writing and modeling you 
believe. This dipole will also work above 20 meters, but the pattern 
gets a bit crazy, and there will be places where it too will not tune 
easily, or be an efficient radiator, even with a good manual tuner. An 
80 meter dipole, however, does work pretty well on 10 meters.

The frustrating, yet sometimes fun thing about antennas, is that one 
antenna seldom meets all needs. So string up whatever you can, then 
take to the air and have fun with it!

Mike Duke, K5XU
American Council of Blind Radio Amateurs