Antennas that work

First keep in mind that any antenna put up in good weather and comfortable conditions simply won’t work. This morning it was 22 degrees out, making it almost perfect for hanging some wire in the trees (had it been dark or raining success would have been guaranteed). It was 68 and sunny when I put up the last antenna and it just didn’t work out so I had to take it down, now the one before that was put up during a freak snow storm and it has been working great.

Okay, so you don’t want to spend a lot of money but you want to get on the air with a respectable signal and be able to hear as well (and of course it has to work on many bands). The absolute best antenna to start with is the horizontal wire loop fed with ladder line or directly from a transmatch (antenna tuner). You will hear people say these antennas don’t work but those are the people who have never tried one or tried one but did something wrong like feeding it with coax.

The more wire you use and the more area you have within the loop the better it will work with the ideal height being in the 30-40 foot range. Mine are made from insulated wire and just weaved through the trees but if you have clear space you can use bare wire and suspend it on four corner insulators. There is nothing critical about this antenna which makes it very easy to setup. If you are feeding it with ladder line keep the line clear of metal objects and put about one twist per foot in the line. The lowest band you want to work determines the minimum size for 160 meters you want at least 400’ of wire and ideally 520’; for 80 meters at least 200’ but 260 is better; on 40 meters 100 or more, etc.

You will need a good transmatch and this is where you should put your money by getting the best one you can afford. The 300 watt MFJ units are OK but if you can manage a full size unit you will be much better off. I use the MFJ 989 which is rated for 3 kilowatts even though I only run 100 watts but the key is it’s much more efficient than the smaller units. The Ten Tec 238 is a great unit but is pricey and a little quirky to operate. Key features are a roller inductor and good built-in balun which are major advantages over the smaller units.

When I got my first transmatch I had no idea how to set it and the directions weren’t much help so I’ll try to explain the steps here. First you want to do your tests on a frequency that is not in use and preferably at times when the band is dead, for example test 80 meters in the middle of the day when there is no long distance propagation. Start by setting the capacitors about mid way, they are usually labeled ‘transmitter’ and ‘antenna’ and have a scale from 0-10. Then adjust the inductor until you find the spot where the static is loudest (Tip – if there is a turns counter set the inductor at minimum and reset the turns counter there – they tend to drift and starting with a good reference will allow you to reset it later). Now adjust each capacitor until the static noise is loudest.

Turn your transmit power down to just a few watts and transmit a carrier while watching the SWR meter and adjust the inductor and caps to find the lowest SWR (I have seen a few comments about IDing when tuning up but the FCC allows short test transmissions without the need to ID, but keep it short!) I prefer to use the SWR meter on the radio since that’s the closest to the transmitter itself and therefore where you want to least reflected power but if you don’t have one the meter in the transmatch will do fine. Once you get the lowest SWR turn up the power a little at a time and touch up the settings (very small adjustments) now that you will see more movement on the meter. This part should not take more than 30 seconds the first time and be much quicker once you have experience. Next write down the frequency and settings, I just go from left to right so starting with the frequency it looks like this (3.8 3.3/6.9/39 7:00) the last entry is the position of the inductor knob as the turn counter is not accurate.

Once you have a chart with multiple settings for each band (record settings about every 0.1 MHz like 3.6, 3.7, 3.8, 3.9…) you should be able to change bands and be ready to go in a matter of seconds. If everybody did this you wouldn’t hear those long carriers covering up that station you are trying to work…

To give you an idea of how well the horizontal loop works; during a casual effort during the CQWW 160 Meter Phone contest this past weekend I was able to work 34 States and several DX stations including one in Germany using just the one antenna. Which is quite impressive since 160 Meters is the most difficult band to work DX.

If you’ve got questions leave a comment or email me
73 de ke4juh

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