Re: [RCSE] Antenna for HLG
On Fri, Apr 23, 2004 at 10:04:36AM -0700, Joe Parsons wrote: | I'm building my second Omega HLG (wore out the first one). | | This one will have a Hitech Electron 6 Rx instead of the 555 I used in the | other HLG | | For aesthetic reasons, I'd like to avoid the excess wire trailing out the | fuse. | | I've thought about just coiling the full length of the antenna wire on a | balsa shaft in the fuse, but I'm wondering whether there are other reliable | approaches. I've got an Omega HLG, and I didn't have to do anything special with the antenna -- it just fit. Your standard 1/4 wave 72 mhz antenna is almost exactly one meter long, and there should be plenty of room in the fuse to just run it from the front to the back. I've seen 72 mhz receivers with shorter antennas (probably having a loading coil inside) but never one with a longer antenna. Are there any? We are talking about the same plane, right? http://www.nesail.com/detail.php?productID=16 You might have to put the receiver farther forward than you might otherwise, or mount it where you want to and the run the antenna forward for a little and then back to the tail, but there should be plenty of room for it. Doubling the antenna back on itself for a few inches will indeed reduce range, but not by a large amount if you only do it for a few inches. But whatever you do, do not just cut the antenna and shorten it -- making it shorter than 1/4 wavelength will greatly reduce range. It's much better to just leave it the same length and coil up a small part of it, the less the better. -- Doug McLaren, [EMAIL PROTECTED]Can't sleep ... clowns will eat me. 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.
[RCSE] Stoopid battery question #764
I'm making up a flight pack of 4 new NiMH 2/3 AAA cells. The polarity is not marked on the cells, but there's an indent at one end. Is that the positive? Joe Parsons 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
At 02:32 PM 4/23/2004, you wrote: On Fri, Apr 23, 2004 at 10:04:36AM -0700, Joe Parsons wrote: | I'm building my second Omega HLG (wore out the first one). | | This one will have a Hitech Electron 6 Rx instead of the 555 I used in the | other HLG | | For aesthetic reasons, I'd like to avoid the excess wire trailing out the | fuse. | | I've thought about just coiling the full length of the antenna wire on a | balsa shaft in the fuse, but I'm wondering whether there are other reliable | approaches. I've got an Omega HLG, and I didn't have to do anything special with the antenna -- it just fit. Your standard 1/4 wave 72 mhz antenna is almost exactly one meter long, and there should be plenty of room in the fuse to just run it from the front to the back. I've seen 72 mhz receivers with shorter antennas (probably having a loading coil inside) but never one with a longer antenna. Are there any? We are talking about the same plane, right? http://www.nesail.com/detail.php?productID=16 Yep, that's the one. You might have to put the receiver farther forward than you might otherwise, or mount it where you want to and the run the antenna forward for a little and then back to the tail, but there should be plenty of room for it. Hmm. I also have a Min-Ellipse, which is close to the same size, and there are several inches dangling out of the back. But, now that I think of it, I may have installed the Rx further aft than in the Omega. Doubling the antenna back on itself for a few inches will indeed reduce range, but not by a large amount if you only do it for a few inches. Well, if the Electron is anything like the 555, range is certainly not an issue. But whatever you do, do not just cut the antenna and shorten it -- making it shorter than 1/4 wavelength will greatly reduce range. It's much better to just leave it the same length and coil up a small part of it, the less the better. Gotcha. Thanks! Joe Parsons -- Doug McLaren, [EMAIL PROTECTED]Can't sleep ... clowns will eat me. 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
On another topic, has anyone ever had glitch problems from power lines? I have been flying at a small lake that is sort of in a canyon surrounded by power lines around the lake area and I have had severe glitching on a Hitec Electron, a DSP 4w10ampBec. a Hitec 555 and a GWS rx. All of these RX's were glitching when the plane was within 300'. There is also a cell phone relay that may come into play above a certain altitude. I have always had minor glitching with the GWS RX's beyond 300ft., but the Hitec's are usually solid. I will try one of the new PLL RX's next.. I don't find this too unusual. I have experienced this in the past on 50 mHz and now make it a practice to stay well away from ANY high voltage power lines, especially those on towers. The ones you find on standard power poles feeding local rural areas don't seem to radiate near as much interferring RF, but close up I've still experienced some problems. I suspect the same applies to 35 and 72 mHz also. I once managed to hang my Heithecker Challenger on the lines crossing the AMA field in Muncie during one of the early Nostalgia events. This was a direct result of interference from the power lines. I was out over the lines when it occurred to me that the plane was in a bad place and said to my caller that I'd better clear the area - but it was a bit too late as the plane rolled over and dived into the lines. Had it been anything other than a 'woodie' it would have been vaporized epoxy and floating carbon filaments - as some others have found out lately. 8-) Unfortunately for me, one of the rules at the NATS is that you cannot take your transmitter with you to retrieve a plane, even if you are the only one on the frequency. As we were riding a golf cart to the scene, the wind changed directions, the plane rotated around the leading edge and fell away from the lines. If I'd had the transmitter I may have been able to fly it away and prevent any further damage. As it was, it spiraled down to a hard landing with considerable additional damage. regards, Jim Porter Neckargemund-Dilsberg Germany INDECISION is the key to FLEXIBILITY 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] Stoopid battery question #764
On Fri, Apr 23, 2004 at 02:33:26PM -0700, Joe Parsons wrote: | I'm making up a flight pack of 4 new NiMH 2/3 AAA cells. | | The polarity is not marked on the cells, but there's an indent at one end. Usually there's a `button' of sorts at the positive end, even for cells advertised as not having a button. But I guess there doesn't have to be ... | Is that the positive? Sounds like it. But why guess? Go down to Harbor Freight Tools (if you're in California as your domain suggests, they're all over) and buy yourself one of their cheap digital multimeters. Look for something like this -- http://www.harborfreight.com/cpi/ctaf/Category.taf?categoryid=170pricetype=Scategoryname=BATTERY%20VOLT%20TESTERS Yes, that's right -- $2.99. Cheap cheap! They're not the world's greatest, but they're dirt cheap, and they're pretty accurate, within 1% anyways for simple things like DC voltage. Add an appropriate resistor (like 15 ohms, 1 watt) in parallel and you've made yourself a fine ESV. (Of course, you can buy a multimeter anywhere, but you're not likely to find them this cheap.) I've used a number of these, and I really can't find anything that wrong with them. Sure, they don't do as many digits as some, and probably don't measure RMS AC voltage very accurately for something that's not a clean sine wave, but you can't beat the price. -- Doug McLaren, [EMAIL PROTECTED] I don't need a compass to know which way the wind shines! --Mr. Furious 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] Stoopid battery question #764
Great question Joe. Not sure what indent represents. However, the negative (-) end is flat with no protrusions, and forms the side of the battery as well. The positive (+) usually will have a protrusion (button) which is electrically isolated form the bottom/sides. If you have a volt meter, you can touch both the top and bottom and observe polarity. If the red lead is on the positive, the VM will display a +V, if reversed you will see -V. Joe Parsons wrote: I'm making up a flight pack of 4 new NiMH 2/3 AAA cells. The polarity is not marked on the cells, but there's an indent at one end. Is that the positive? Joe Parsons 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. 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.
RE: [RCSE] Antenna for HLG
I've got the same plane - I replaced the standard antenna with lightweight aluminum wire (wire wrapping wire, and cut off the excess - no problem. You're not going to be operating a hand-launch at nearly the range you would with a bigger ship, as you wouldn't be able to see it. Matt -Original Message- From: Joe Parsons [mailto:[EMAIL PROTECTED] Sent: Friday, April 23, 2004 1:05 PM To: RCSE Subject: [RCSE] Antenna for HLG I'm building my second Omega HLG (wore out the first one). This one will have a Hitech Electron 6 Rx instead of the 555 I used in the other HLG For aesthetic reasons, I'd like to avoid the excess wire trailing out the fuse. I've thought about just coiling the full length of the antenna wire on a balsa shaft in the fuse, but I'm wondering whether there are other reliable approaches. Suggestions? Joe Parsons 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. 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] Stoopid battery question #764
Just measure the voltage - if the red wire is on positive, you'll get some positive reading,or else a needle pinned to the left if red is on negative (with a digital MM, you'll get a negative voltage) Matt -Original Message- From: Joe Parsons [mailto:[EMAIL PROTECTED] Sent: Friday, April 23, 2004 5:33 PM To: RCSE Subject: [RCSE] Stoopid battery question #764 I'm making up a flight pack of 4 new NiMH 2/3 AAA cells. The polarity is not marked on the cells, but there's an indent at one end. Is that the positive? Joe Parsons 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. 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.
[RCSE] Tri-County Glider Contest
Hawks, I saw a reference to the Tri-County Barnstormers Glider Contest for May 22nd. That's the weekend before the Deep-South and they always have some prizes. I won a pair of Hitec 55 Servos last time I was there. Not bad for a country boy. We should attend and support our neighbor clubs. I'm going Jack __ Do you Yahoo!? Yahoo! Photos: High-quality 4x6 digital prints for 25ยข http://photos.yahoo.com/ph/print_splash 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
I've been using some Litz wire on my HLGs. Works really well and is very light. I'm using a version that has 20 #44 wires twisted with a nylon strand. Each wire is like small magnet wire as it's insolated with a coating. The coating burns off when soldering, so each strand makes contact. Stranded wire is good for several reasons It doesn't break with bending, and RF likes lots of surface area to run on. The nylon strand is great for CAing down where I want it tacked. Bob Vixie Colorado Springs, CO - Original Message - From: Joe Parsons [EMAIL PROTECTED] To: RCSE [EMAIL PROTECTED] Sent: Friday, April 23, 2004 11:04 AM Subject: [RCSE] Antenna for HLG I'm building my second Omega HLG (wore out the first one). This one will have a Hitech Electron 6 Rx instead of the 555 I used in the other HLG For aesthetic reasons, I'd like to avoid the excess wire trailing out the fuse. I've thought about just coiling the full length of the antenna wire on a balsa shaft in the fuse, but I'm wondering whether there are other reliable approaches. Suggestions? Joe Parsons 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. 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.
[RCSE] WTB: 3.45-meter Full D-Box Graphite Wing
Please contact me off line, email address: elvis 'at' monkeytumble.com Hasta, Jay Decker 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.
[RCSE] WTB: 3.45-meter Full D-Box Graphite Wing
Please contact me off line, email address: elvis 'at' monkeytumble.com Hasta, Jay Decker 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.
