Re: [RCSE] Antenna for HLG / Electric Fields
I take it no one has informed you of this; We regularly charge the airframe with negative ions to help core the postively charged thermals... Tom H. Nagel wrote: Gentlemen: I refer you to a recent article on Space.Com about the recent discovery that dust devils carry an enormous electrical charge. This terrestrial research is being extrapolated to Mars, where things are a lot drier and dust devils are a lot bigger. Of course, we know that tornados throw off radio frequency signals. That is why you can detect them on certain TV channels. All of which gets me to wondering if our everyday thermals generate electrical fields? And if that gives me an excuse for never being able to stay in a thermal very long despite really really trying hard to do so? Tom H. Nagel Columbus, OH - Original Message - From: Art Mcnamee mailto:[EMAIL PROTECTED] To: Aerofoam mailto:[EMAIL PROTECTED] ; RCSE mailto:[EMAIL PROTECTED] ; Martin Usher mailto:[EMAIL PROTECTED] Sent: Saturday, April 24, 2004 3:49 PM Subject: Re: [RCSE] Antenna for HLG / Electric Fields Hi Martin, Wire lines have fields around them depending on the voltage and also when, if, the insulators were cleaned and if the transformers are properly grounded. The noise can completely blank out your receiver if you get too near the lines so stay away from them.Drive your car with the radio on AM and go under power lines at intersections. The noise will tell you lots. Thermals, Art - Original Message - From: Martin Usher mailto:[EMAIL PROTECTED] To: RCSE mailto:[EMAIL PROTECTED];Aerofoam mailto:[EMAIL PROTECTED] Sent: 4/23/2004 5:13:49 PM Subject: Re: [RCSE] Antenna for HLG / Electric Fields On another topic, has anyone ever had glitch problems from power lines? (Mark Mech / Aerofoam) In the current edition of Smithsonian there is a two page color photograph of an outdoor art piece made by sticking about a thousand flourescent tubes vertically into the ground under some high tension wires. The photograph is taken at dusk and the tubes are all glowing. This is an extreme example but it illustrates the significant electrical fields that high voltage transmission lines give off. It will affect a radio receiver, possibly enough to make it glitch. The question I can't answer is how much is enough -- how close can you go to what lines without experiencing problems. The art piece was done under 400kV lines; I don't think anyone's going to be flying near those, but what about lower voltage lines? We have neighborhood distribution lines running down one side of our field and they don't affect our flying (assuming that nobody actually lands on them, that is). I don't know what voltage they are, I think its 7kV. If they were significantly higher voltage then the poles they are on would be a lot taller and we'd be avoiding them just like any other obstacle. . Martin Usher --- Art Mcnamee --- [EMAIL PROTECTED] mailto:[EMAIL PROTECTED] --- EarthLink: It's your Internet. RCSE-List facilities provided by Model Airplane News. Send subscribe and unsubscribe requests to [EMAIL PROTECTED] Please note that subscribe and unsubscribe messages must be sent in text only format with MIME turned off.
Re: [RCSE] Antenna for HLG / Electric Fields
On another topic, has anyone ever had glitch problems from power lines? (Mark Mech / Aerofoam) In the current edition of Smithsonian there is a two page color photograph of an outdoor art piece made by sticking about a thousand flourescent tubes vertically into the ground under some high tension wires. The photograph is taken at dusk and the tubes are all glowing. This is an extreme example but it illustrates the significant electrical fields that high voltage transmission lines give off. It will affect a radio receiver, possibly enough to make it glitch. The question I can't answer is how much is enough -- how close can you go to what lines without experiencing problems. The art piece was done under 400kV lines; I don't think anyone's going to be flying near those, but what about lower voltage lines? We have neighborhood distribution lines running down one side of our field and they don't affect our flying (assuming that nobody actually lands on them, that is). I don't know what voltage they are, I think its 7kV. If they were significantly higher voltage then the poles they are on would be a lot taller and we'd be avoiding them just like any other obstacle. . Martin Usher RCSE-List facilities provided by Model Airplane News. Send subscribe and unsubscribe requests to [EMAIL PROTECTED] Please note that subscribe and unsubscribe messages must be sent in text only format with MIME turned off.
Re: [RCSE] Antenna for HLG / Electric Fields
On Fri, Apr 23, 2004 at 05:13:49PM -0700, Martin Usher wrote: On another topic, has anyone ever had glitch problems from power lines? (Mark Mech / Aerofoam) In the current edition of Smithsonian there is a two page color photograph of an outdoor art piece made by sticking about a thousand flourescent tubes vertically into the ground under some high tension wires. The photograph is taken at dusk and the tubes are all glowing. This would be Richard Box's work, http://www.richardbox.com/ . Click on the main graphic or the archive link to see the other cool bits he's done. This is an extreme example but it illustrates the significant electrical fields that high voltage transmission lines give off. It will affect a radio receiver, possibly enough to make it glitch. The question I can't answer is how much is enough -- how close can you go to what lines without experiencing problems. The art piece was done under 400kV lines; I don't think anyone's going to be flying near those, but what about lower voltage lines? Remember that a Red Herring isn't quite big or conductive enough to do too much damage, but I've successfully flown underneath / in between these lines for an hour or so with only one or two glitches out of a GWS 4 channel single conversion receiver: http://www.diff.net/media/2002_07_10_Oregon_trip/img_5872-medium.html I'm not sure if I'm comfortable saying this in a public forum, but the plane mostly glitches when you whack the lines (remember, with 4.5 ounces of white foam.) The lines were about 5' above my max launch, so I didn't spend too much time up that high. I do not know the voltage of those lines, but it's line 1, mile 18, tower 2 in Hillsboro, OR, if anybody wants to look it up :) We have neighborhood distribution lines running down one side of our field and they don't affect our flying (assuming that nobody actually lands on them, that is). I don't know what voltage they are, I think its 7kV. If they were significantly higher voltage then the poles they are on would be a lot taller and we'd be avoiding them just like any other obstacle. So people have demonstrated solar powered planes from the sun and from spotlights (NASA Dryden), as well as from lasers. Has anybody done to math to see whether an inductively powered plane could be flown under high lines? There are several technical challenges I can think of, but it would be a neat way to get the power companies to absolutely hate you... -Peter (Please, take all homeland security discussions off-list; this is about interference and overload in receivers when flying in the vicinity but not through power lines.) -- Peter Jensen ... http://www.diff.net/peter ... [EMAIL PROTECTED] RCSE-List facilities provided by Model Airplane News. Send subscribe and unsubscribe requests to [EMAIL PROTECTED] Please note that subscribe and unsubscribe messages must be sent in text only format with MIME turned off.
