Hello Martin There is one factor here which is an absolute and which is beyond our control. Over here in the UK, the majority of town-based homes have a front, and sometimes, a back garden. This is the case with our house. We don't live in an area where land is a premium; and the logistics of mounting an anywhere close to efficient antenna as I've seen them in both books and in practical situations without intruding on to our neighbour's land would simply not be workable.
Beams are also out of the question Martin because of the physical dimensions and the space required to rotate them. So you can be as detailed as you wish, but there's no way that we would be prepared to invest the time and money required to do the job properly. It's simply not workable, end of story I'm afraid. Were it workable, I'd be more than happy to let Gordon loose on the HF bands again. Lynne, (spelled with a trailing letter "e", by the way. ;-) On 4 Apr 2012, at 20:20, Martin McCormick <[email protected]> wrote: I promise not to go in to tons of details, but radio antennas share something in common with musical instruments. While the physics of air don't seem to have a lot in common with electrons, they do create resonances which are based on the size of the paths that the electrons or air molecules follow so low frequencies such as a base pipe organ note or a bassoon require physically large pipes to make the low notes. piccolo and penny whistles are small because they make high notes and the airways must be very short. Radio antennas are governed by the same natural laws except that it is not air but electrons that bounce around in conductors which behave just like organ pipes only for electrons. That means antennas for low frequencies such as HF must be physically larger than antennas for VHF 2-meters and UHF 70-CM and above. There are tricks you can play, however, to make low-frequency antennas smaller than they normally would be but still resonate. Nothing comes for free, though, and the tradeoff is efficiency. The RSGB and ARRL have all kinds of books on how to make various types of antennas and there are sections on what are called "stealth antennas." These are antennas either disguised as something else like a flag pole or are made out of materials that are very hard to see such as fine wire. The fine wire antennas break more often, of course, but some are almost invisible. Stealthy antennas are designed for amateurs who either have fussy neighbors or who are forced to live in neighborhoods with bans on outdoor antennas. The books tell you how to build such antennas in a safe manner so that you don't expose yourself or your neighbors to high-level electromagnetic radiation which may or may not be harmful to the body and can sometimes disrupt consumer electronics such as music systems, computers, etc. The wave lengths such as 2-meters, 6-meters, 70 centameters, etc, describe the distance between the waves as they fly out from the antenna like ripples on a pond. In this case, they fly at the speed of light. "Mrs. Lynnette Annabel Smith" writes: > Gordon is, like you, a radio amateur. I think he's talked about that > before; and it's something which we would like to bring back within his > reach but due to problems on the premises the only antenna he currently > can have is a 2 meter and 70CM vertical; I don't understand the technical > bits of that. But an HF antenna is out of the question now as we don't > have a great deal of space, and we no longer have cooperative neighbours. ======================================= The Techno-Chat E-Mail forum is guaranteed malware, spyware, Trojan, virus and worm-free To modify your subscription options, please visit for forum's dedicated web pages located at http://mail.tft-bbs.co.uk/mailman/listinfo/techno-chat You can find an archive of all messages posted to the Techno-Chat group at either of the following websites: http://mail.tft-bbs.co.uk/pipermail/techno-chat/index.html Or: <http://www.mail-archive.com/[email protected]> you may also subscribe to this list via RSS. The feed is at: <http://www.mail-archive.com/[email protected]/maillist.xml> --------------------------------------- ======================================= The Techno-Chat E-Mail forum is guaranteed malware, spyware, Trojan, virus and worm-free To modify your subscription options, please visit for forum's dedicated web pages located at http://mail.tft-bbs.co.uk/mailman/listinfo/techno-chat You can find an archive of all messages posted to the Techno-Chat group at either of the following websites: http://mail.tft-bbs.co.uk/pipermail/techno-chat/index.html Or: <http://www.mail-archive.com/[email protected]> you may also subscribe to this list via RSS. The feed is at: <http://www.mail-archive.com/[email protected]/maillist.xml> ---------------------------------------
