Topband: "Magnetic Receiving Loop / small loop , brief summary.
Jim Kearman
jkearman at att.net
Thu Dec 22 08:51:36 EST 2005
> So it pays to play around a bit. And it only costs a
> bit of time.
While it is good news that so many hams are building exceptional stations for the low bands, I worry that people who can't build exceptional stations will shy away for fear they cannot make contacts unless they have Beverages and large vertical transmitting antennas. I recommend K1ZM's book for the historical background. Back in the day, many QSOs were made with marginal antennas at stations running as little as 10 watts. Yes, you want to have the best station possible, but the key word is "possible."
The advantage of a loop antenna is its portability. I use a large coax loop on 80 at the moment. I can carry it outside when I want to operate, and bring it in when I'm finished. I use an inverted-L transmitting antenna with not enough radials, but I was able to work 87 countries in one night in the CQWW. If there is a design problem with the ARRL loop and its descendants, the low-band community would do itself a tremendous favor by publishing a version that works correctly. But I must say that the trimmer in the one I use tunes to a peak in the same place regardless of feedline length, and allows me to hear stations inaudible on my inverted-L.
Were I less experienced I might fall prey to the notion that I couldn't operate on the low bands from my condo complex. So, while we push the envelope, we also need to facilitate operation by more people. Ham radio is on the wane worldwide, despite decades of lowering the entry bar. Declining solar activity is going to hasten its demise. We could do ourselves a lot of good by convincing Tim Tribander to try the low bands.
Many successful low-band operators seem to have forgotten their roots. Who ever started out with 1500 W, phased verticals, and several Beverage antennas? Arcane knowledge and the appearance of exclusivity feed the ego, but don't do much to increase activity. IMO the ON4UN book has progressed from a pretty useful handbook to a photo album of big-gun stations, with small-scale antenna possibilities tossed in as an a sidebar. We need a beginner's guide to 160. As I get active on 160 and develop some experience I will post information on my Website ( http://kr1s.kearman.com/ ), but we could use it now. For starters, how about a portable loop antenna that is built according to good engineering practice?
73,
Jim, KR1S
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