THE IMPORTANCE OF ANTENNA PLACEMENT

The antenna is often the unsung hero of our amateur radio station.  An efficient, resonnant antenna is a beautiful thing.  As proven over and over, even a mediocre antenna can get you on the air, but you also miss a lot of the weaker stations.  Unfortunately, a lot of people stop at this point and never try to do better.  Sometimes it seems easier to just buy a new radio with lots of gizmos instead, and hope for the best.

The antenna has to be viewed as part of a whole system.  Even the most sophisticated radio known to man is useless without it.  In fact, many will argue that the antenna system (antenna, feedline, switches…) is far more important than the radio itself.  Money spent on an antenna system often yields more rewards than if it were spent on other radio accessories.  Unlike amplifiers, any gain realized by a more effective antenna is useful for both receive and transmit.

Recently the importance of antenna placement was displayed to me in a very real way.  At the WD9BSA Scout Radio Station we have two HF antennas.  Both are multi-band and shortened antennas.  Outside we have a what’s become almost a standard among muliti-bander–the G5RV.  Loved by some and reviled by others.  Mounted in the station attic is an Alpha Delta DXCC–another very popular multi-bander.  I haven’t checked the numbers but I suspect they’re both capable of the the same performance levels when averaged across all bands.

We were working a station on 40m using a Ten Tec Argonaut V into the G5RV.  We were hearing him well, though he reported that we were a little down.  This is probably due to the fact that the Argo only makes about 25W PEP max.  We thought we should try working him on the Yaesu FT-900 since it’s a standard 100W radio.but he seemed a little weak on receive.  We actually had a hard time hearing him.  So we hit the Tune button and cranked up to 100W and tried him on the DXCC.  Our patient operator said he could hear us better with the Argo…we were barely readable on the Yaesu even with four times the power.

This prompted us to do some testing.  We put a coax switch on the Yaesu and connected both antennas.  We then tuned around and copied different stations and compared the receive signal.  What we found was a 10dB improvement by using the outdoor G5RV over the attic mounted DXCC.  To put this in another way, just under two S-units improvement (1 S-unit=6dB)  In addition, we found that on the DXCC not only was the station we were listening to lower in signal, but the noise level was higher (probably due to noise generated in the building).  Talk about a worst case scenario–weaker signal and higher noise to overcome!

So never fear…I’m not hating on wire multi-band antennas.  If that’s the best option given your situation then that’s what you should use.  I believe any antenna that allows you to put QSO’s in the log is better than sitting around wishing.  I love my hexbeam on the tower, but I still make a lot of contacts on a Carolina Windom 80.  My suggestion is to make the best with what you have and enjoy making QSO’s.  However try to maximize your signals if possible by not adding additional handicap to your efforts with poor placement.  I’d really love to see what that DXCC could do out in the open!

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Categories: Activities, Amateur Radio | 2 Comments

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2 thoughts on “THE IMPORTANCE OF ANTENNA PLACEMENT

  1. Tabb Adams

    Good stuff Jeff, its all about the antenna!

  2. Great post. I do think that a G5RV is good if you have limited space for antennas, but good god man don’t put it in the attic unless there is no way put it outdoors. Some hams in HOA areas must put something in the attic since they cannot operate any other way. It’s about sacrifice and compromise. Hams like us understand that a beam beats a G5RV every time but we cannot put up a beam. I have heard good things about the DX-CC. But I agree get it outside and as high as you can. – Nick N9SJA

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