Date: Sat, 14 Jan 95 21:19:00 -0400 From: "Robert O. Cherney" Subject: Re: Radio Systems Technology ??? and Cozy MKIV's Hi Marc: I've had the same problem. I ordered some antenna parts back in October and have yet to receive them. I have located other sources of the RG58A/U and the torroids. I have not looked for the copper foil tape since I'm making a coaxial vertical dipole out of 1/4" copper thinwall water tubing. If you need the information on the torroids, let me know. By the way, I'm building a Berkut. Rob- +------------------------------------------------------------------------+ | Rob Cherney E-Mail: p00836@psilink.com | | Ellicott City, Maryland Home Phone: (410) 465-5598 | | U.S.A. Work Phone: (410) 785-6250 ext. 254 | +------------------------------------------------------------------------+ Date: Mon, 16 Jan 95 8:49:14 EST Subject: Re: Radio Systems Technology ??? and Cozy MKIV's Rob; >I've had the same problem. I ordered some antenna parts back in October >and have yet to receive them. I have located other sources of the >RG58A/U and the torroids. I have not looked for the copper foil tape since >I'm making a coaxial vertical dipole out of 1/4" copper thinwall water >tubing. Geez, that's pretty bad. I've managed to get in touch with a human there, and they said they've just re-organized, so maybe things will get better. >If you need the information on the torroids, let me know. Thanks. If RST doesn't come through, I'll do just that. >By the way, I'm building a Berkut. Just out of curiosity, what's the difference between that and a Lonz-Eze? -- Marc J. Zeitlin E-Mail: marcz@an.hp.com Date: Tue, 7 Feb 95 13:28:26 EST Subject: Re: Radio Systems Technology ???/coax and torroids Rob; >>I've had the same problem. I ordered some antenna parts back in October >>and have yet to receive them. I have located other sources of the >>RG58A/U and the torroids. I have not looked for the copper foil tape since >>I'm making a coaxial vertical dipole out of 1/4" copper thinwall water >>tubing. >>If you need the information on the torroids, let me know. Well, it's been a month since speaking to RST; I can't get through to them again, and I'm getting nervous about getting antennae parts and instructions. Where have you gotten your stuff? And why are you using 1/4" copper thinwall water tubing instead of copper foil tape? Is this something we should all consider? If so, do you have instructions for it (or even instructions for the tape version)? Thanks - I hope I'm not bothering you (too much :-) ). -- Marc J. Zeitlin E-Mail: marcz@an.hp.com Date: Tue, 07 Feb 95 19:51:01 -0400 From: "Robert O. Cherney" Subject: Re: Radio Systems Technology ???/coax and torroids >Well, it's been a month since speaking to RST; I can't get through to them >again, and I'm getting nervous about getting antennae parts and >instructions. Where have you gotten your stuff? And why are you using >1/4" copper thinwall water tubing instead of copper foil tape? Is this >something we should all consider? If so, do you have instructions for it >(or even instructions for the tape version)? I have performed some experiments using a configuration known as a coaxial dipole. This configuration is like a dipole -- it has two radiating elements -- but it configures the lower element with a tube that surrounds the coaxial feed cable, and is connected at the feed point. My hope was that this configuration would be better since the coaxial feed is not disturbing the uniformity of the radiation pattern. After some experimentation, I have placed this project on the back burner. My problem was obtaining an acceptable VSWR (Voltage Standing Wave Ratio). The VSWR is a ratio that relates antenna impedance to transmitter impedance. The lower the ratio the better. One-to-one is ideal. If this is confusing, find some Ham Radio operator to explain it to you. I may ressurect the experimentation if I can obtain a good network analyzer that covers the 108-136MHz aviation band. A VSWR meter does not give me enough information to design an antenna (maybe you can use your H/P connections :) ). So, for now, I'm using the RST configuration in my Berkut. I've built one winglet with the vertical dipole and it performs well. The materials I have used are: 1) Teflon (plenum rated) 50-Ohm local area network cable, 2) Ferrite beads from Amidon Associates 3) 1/2-inch Pressure sensitive copper tape from 3M The Teflon coax cable was obtained from a local LAN installer. I used this cable because it is smaller in diameter than the recommended RG-58 A/U coax, has the same loss characteristics, has better shielding properties, and it is easier to solder because it doesn't melt. If you have to buy it from a supplier, you will have to purchase an entire 1,000 ft. roll. A LAN installer will sell you a small amount for about $1 per foot. The cable designator is Belden E-89907 P/N 1701246, although other manufacturers sell an equivalent product. Make sure it has a stranded center conductor. Four ferrite beads are placed over the coax cable near the feed point of the dipole. Together, these make a BALUN (a device that matches a BALanced antenna to an UNbalanced cable). They also prevent the shield of the coax from radiating and upsetting your avionics. I used Amidon Associates P/N FB-43-2401. These cost $4.50 per dozen. These beads will fit easily over Teflon coax, but will be difficult to fit over RG-58 A/U. You might want to get the next bigger inside diameter. The important thing is to specify material formulation 43, which gives the highest impedance at 130MHz. Amidon Associates is in Santa Ana, CA but I don't have their telephone number. The copper foil tape I got from work, but I know it is made by 3M products. It has a pressure-sensitive adhesive backing and is 1/2-inch wide. Each of the two radiating elements is 20.3" long. I am concerned about the adhesive causing a fiberglass delamination later on, so the next antenna will be made using copper foil that has been epoxied to the foam winglet core. Be very careful of the coax cable you buy. Use a name brand such as Belden or Alpha unless you are sure of it's quality. Some have very poor braid coverage which will result in poor shielding against the noise coming from your digital avionics. I have also seen some cases of RF feedback getting into an intercom system and one case that would upset these new active headphones. I would, as a rule, avoid the coax that Radio Shack sells since I cannot readily assess the quality. >Thanks - I hope I'm not bothering you (too much :-) ). No problem, at all. Call or E-mail if you have any more questions. Rob- +------------------------------------------------------------------------+ | Rob Cherney E-Mail: p00836@psilink.com | | Ellicott City, Maryland Home Phone: (410) 465-5598 | | U.S.A. Work Phone: (410) 785-6250 ext. 254 | +------------------------------------------------------------------------+ Date: Wed, 8 Feb 95 9:56:47 EST Subject: Re: Radio Systems Technology ???/coax and torroids (fwd) People; I received this information about antennae systems from Robert Cherney (a Berkut builder) and thought you might be interested. >So, for now, I'm using the RST configuration in my Berkut. I've built one >winglet with the vertical dipole and it performs well. The materials I >have used are: > 1) Teflon (plenum rated) 50-Ohm local area network cable, > 2) Ferrite beads from Amidon Associates > 3) 1/2-inch Pressure sensitive copper tape from 3M > >The Teflon coax cable was obtained from a local LAN installer. I used this >cable because it is smaller in diameter than the recommended RG-58 A/U coax, >has the same loss characteristics, has better shielding properties, and it >is easier to solder because it doesn't melt. If you have to buy it >from a supplier, you will have to purchase an entire 1,000 ft. roll. A LAN >installer will sell you a small amount for about $1 per foot. The cable >designator is Belden E-89907 P/N 1701246, although other manufacturers sell >an equivalent product. Make sure it has a stranded center conductor. > >Four ferrite beads are placed over the coax cable near the feed point of >the dipole. Together, these make a BALUN (a device that matches a BALanced >antenna to an UNbalanced cable). They also prevent the shield of the coax >from radiating and upsetting your avionics. I used Amidon Associates >P/N FB-43-2401. These cost $4.50 per dozen. These beads will fit easily >over Teflon coax, but will be difficult to fit over RG-58 A/U. You might >want to get the next bigger inside diameter. The important thing is to >specify material formulation 43, which gives the highest impedance at >130MHz. Amidon Associates is in Santa Ana, CA but I don't have their >telephone number. > >The copper foil tape I got from work, but I know it is made by 3M products. >It has a pressure-sensitive adhesive backing and is 1/2-inch wide. Each >of the two radiating elements is 20.3" long. I am concerned about the >adhesive causing a fiberglass delamination later on, so the next antenna >will be made using copper foil that has been epoxied to the foam winglet core. > >Be very careful of the coax cable you buy. Use a name brand such as Belden >or Alpha unless you are sure of it's quality. Some have very poor braid >coverage which will result in poor shielding against the noise coming from >your digital avionics. I have also seen some cases of RF feedback getting >into an intercom system and one case that would upset these new active >headphones. I would, as a rule, avoid the coax that Radio Shack sells >since I cannot readily assess the quality. -- Marc J. Zeitlin E-Mail: marcz@an.hp.com Date: Wed, 8 Feb 95 09:02:34 PST From: "Michael Antares" Subject: Re: Radio Systems Technology ???/coax and torroids (fwd) Amidon Associates is in Santa Ana, CA but I don't have their >>telephone number. Mark, their telephone number is 714-850-4660, FAX is 714-850-1163, address is 3122 Alpine Ave, Santa Ana, 92704. Regards, Michael Michael Antares Software/Hardware Systems Engineering mantares@crl.com Santa Rosa, California Date: Wed, 08 Feb 95 22:20:35 -0400 From: "Robert O. Cherney" Subject: Re: Radio Systems Technology ???/coax and torroids Hi Marc: I just shot Rich Riley (he is in the back seat of the Berkut on the cover of Sport Aviation) an e-mail message asking for permission to send you the antenna pages from my builder's manual. I should hear from him soon. If he says no, I can draw you up something and mail or fax it to you. By the way, what are you building? Later, Rob- +------------------------------------------------------------------------+ | Rob Cherney E-Mail: p00836@psilink.com | | Ellicott City, Maryland Home Phone: (410) 465-5598 | | U.S.A. Work Phone: (410) 785-6250 ext. 254 | +------------------------------------------------------------------------+ Date: Thu, 09 Feb 95 20:51:57 -0400 From: "Robert O. Cherney" Subject: Re: Radio Systems Technology ???/coax and torroids Hiya Marc: Rich Riley said it was OK to copy the pages and mail them to you. I will do same as soon as you let me know what your home address is. The Berkut (and most other canard designs) place the comm antennas in the winglets and the nav antenna in the canard. The only antennas you might want to place in the fuselage is the marker beacon and perhaps the transponder antennas. The information that I will send you is good for the comm antennas in the winglets, although the information can be generalized for other applications. I can give you some hints on this. As a matter of fact, you can help me out. There are a few items re: the Cozy design that I would like information on. The first is Nat's design for a heater system. I understand that he has worked out a nice exhaust muff system. The second is the details of the offset hardware in the canard torque tubes. This hardware places the tubes that penetrate the fuselage on the same axis as the elevator hinge pins. The older Long-EZ and my Berkut kit have an offset that requires a curved slot rather than a hole through the fuselage; this allows cold air into the cockpit in the winter. The specific part that compensates for this is CZNC-12A. I have the drawings for this part, but I don't have the details of how it couples to the rest of the elevator control system. Lastly, I am searching for a left-handed multi-function military-style stick grip. Since the Cozy uses outboard sticks, I thought that there might be some sources mentioned in the newsletter. Glad to help you out. Rob- +------------------------------------------------------------------------+ | Rob Cherney E-Mail: p00836@psilink.com | | Ellicott City, Maryland Home Phone: (410) 465-5598 | | U.S.A. Work Phone: (410) 785-6250 ext. 254 | +------------------------------------------------------------------------+ Date: Fri, 10 Feb 95 9:33:10 EST Subject: Re: Antennae et. al. > >Hiya Marc: > >Rich Riley said it was OK to copy the pages and mail them to you. I will >do same as soon as you let me know what your home address is. Excellent. It's: 47 Flint Rd. Acton, Ma. 01720 >The Berkut (and most other canard designs) place the comm antennas in the >winglets and the nav antenna in the canard. The only antennas you >might want to place in the fuselage is the marker beacon and perhaps the >transponder antennas. The information that I will send you is good for >the comm antennas in the winglets, although the information can be >generalized for other applications. I can give you some hints on this. Love to hear them. I happened to notice two ads in the back of the latest (February 1995) Sport Aviation regarding antennas. One from: Antenna Dynamics, Inc. 11100-8 Sepulveda Blvd., Ste. 565 Mission Hills, Ca. 91345 (818) 831-8640 and another: Advanced Aircraft Electonics P.O. Box 4111 Florissant, Mo. 63032 (800) 758-8632 I'm going to call and ask for whatever info they have - if it's anything interesting, I'll let you know. >As a matter of fact, you can help me out. There are a few items re: the Cozy >design that I would like information on. The first is Nat's design for a >heater system. I understand that he has worked out a nice exhaust muff >system. I'll check out that chapter over the weekend and write up the details for you. >....... The second is the details of the offset hardware in the canard >torque tubes. This hardware places the tubes that penetrate the fuselage >on the same axis as the elevator hinge pins. The older Long-EZ and my >Berkut kit have an offset that requires a curved slot rather than a hole >through the fuselage; this allows cold air into the cockpit in the winter. >The specific part that compensates for this is CZNC-12A. I have the drawings >for this part, but I don't have the details of how it couples to the rest >of the elevator control system. Yes, I remember seeing this set-up and thinking it was nice. I'll get the details for you. >Lastly, I am searching for a left-handed multi-function military-style >stick grip. Since the Cozy uses outboard sticks, I thought that there might >be some sources mentioned in the newsletter. I don't remember seeing a source for the sticks in the newsletters - I'll check again. However, Sport Aviation had an ad from: Northwest Custom Grips 4541 Harlan Dr., NE Salem, Oregon 97305 (503) 463-4433 They advertise teak grips, left or right or sets, with or without PTT and/or 4 position Cooley Hat switches for trim. Custom work welcome. Info pack $3. Also, right above that, is another ad: Kent Schreiber 3751 Williamson Rd. Greencastle, Pa. 17225 He says he will make custom walnut grips, but doesn't mention left or right. Also, only one button on top. I should have the info on the first two questions by Monday - if there's anything else regarding the grips, I'll have that by then, too. -- Marc J. Zeitlin E-Mail: marcz@an.hp.com Date: Thu, 16 Feb 95 9:25:06 EST Subject: Re: Antennae et. al. Robert; >Thanks for the GIFs. They all decoded just dandy. Glad to hear it. >The antenna plans and some notes are "in the mail", as they say. You should >get them in a couple of months if the postal system is working normally. You know, after all this back and forth about antennae (with you and with Eric Westland, who send me copies of a bunch of info originally from RST) I spent some time looking through the Aircraft Spruce Catalog and the Cozy plans, and of course found some information about antennae, including the standard RST-like antenna kit for NAV/COM for $14.95. Anyway, I'm sure all the info will help out, but I feel kind of silly asking all these questions when all I had to do was spend some time searching through literature I already had. Oh well. At least I was able to help you out in return. Were there any other pictures or anything I was supp..... oh yes, the offset bushing attachment to the torque tube and the fuselage hole issue. I'll try to get that info tonight and mail it to you tomorrow (Friday). -- Marc J. Zeitlin E-Mail: marcz@an.hp.com Date: Wed, 31 May 1995 22:27:52 -0700 From: johnw@daktel.com Subject: Re: Nav Antenna <---- Begin Included Message ----> Date: Thu, 1 Jun 1995 00:01:01 -0400 From: Marcnadine@aol.com Subject: Re: Nav Antenna I'm just about to install the nav antenna before I glass the fuse and would like to know if anyone has the phone # for Radio Systems Tech or knows of a good one that they have used. Marc The last catalog that I recieved from RST gives the ph.# of (916)272-2203. John Williams <---- End Included Message ----> Date: Thu, 1 Jun 1995 00:01:01 -0400 From: Marcnadine@aol.com Subject: Re: Nav Antenna I'm just about to install the nav antenna before I glass the fuse and would like to know if anyone has the phone # for Radio Systems Tech or knows of a good one that they have used. Marc Date: Thu, 1 Jun 95 07:19:59 PDT From: "Michael Antares" Subject: Nav Antenna Mark, I just ordered the materials for the antenna from RST at the number posted. I might mention though that you might wait a bit because I think that much of the material can be obtained locally at somewhat lower prices. They (the RST manufacturing people) seem to be very nice and were willing to send only the materials I wanted. In other words they have not kitted these antennas in advance. You might give me a phone call re:... Michael Antares Software/Hardware Systems Engineering mantares@crl.com Santa Rosa, California From: Marc J. Zeitlin Subject: Re: Nav Antenna (fwd) Date: Thu, 1 Jun 95 13:11:21 EDT Marc P. wrote: >I'm just about to install the nav antenna before I glass the fuse and would >like to know if anyone has the phone # for Radio Systems Tech or knows of a >good one that they have used. Others gave the RST phone # and Michael A. said he had just ordered the NAV kit from them. I had a hell of a time getting them to answer the phone a couple of months ago - it seems they may have finally finished their reorganization. (For those of you interested in a bit of trivia, this whole mailing list started when I posted a request in r.a.h. for info on RST, and also asked for other on-line cozy builders. We've gone full circle). At any rate, I bought my antennae kit for the NAV antennae in the fuselage from Aircraft Spruce - something like $14 gets you the copper tape, the coax connectors, the coax, and the toroids. You could probably get the components cheaper from various sources, but you'd have to find them. I've obtained some teflon coax from a friend here at work, so I'm using that instead of the AS supplied stuff. -- Marc J. Zeitlin E-Mail: marcz@an.hp.com Date: Thu, 1 Jun 1995 22:14:20 -0400 From: StetsonE@aol.com Subject: Re: Nav Antenna On 1 June, Marc wrote: >I'm just about to install the nav antenna before I glass the fuse and >would like to know if anyone has the phone # for Radio Systems >Tech or knows of a good one that they have used. The phone number I have for Radio Systems Technology is 800-824-5978, but that number dates back to 1976. As of a year ago they were still in business. So if that nbr doesn't work, try directory assistance. They are located in Grass Valley, CA. I used com and xponder antennas from Bob Archer in Torrance, CA. Phone 310 316 8796. I've heard good reports from others about his antennas, but have yet to get my plane in the air to try them out. His xponder antenna is very interesting. It is mounted on a flat circuit board, mounts vertically, and can be installed at the end of the strake with nothing sticking into the airstream - very neat! I don't know anything about his nav antenna though. The guy seems very knowledgeable - before retiring he worked in one of the aerospace companies and designed antennas for spacecraft! Stet Elliott Perpetual Long-EZ builder StetsonE@aol.com Date: Fri, 2 Jun 1995 12:58:20 -0400 (EDT) From: Tech Support - Rick Subject: Re: Nav Antenna the 916-272-2203 is especially good after 2 p.m. pacific time. I actually talked to them yesterday. Jim Weir just bought the company back from the people he sold it to. They were in foreclosure at the time (last OCT.). Rst is back with friendly people again. They were horrified to learn that I had been trying to cantact them since last year with no response. They were more thatn happy to send me their catalog! Rick Crapse ( now where did that epoxy go?!!? just had it a second ago...Hey! don't eat that! No, it's not honey!) On Thu, 1 Jun 1995 StetsonE@aol.com wrote: > On 1 June, Marc wrote: > >I'm just about to install the nav antenna before I glass the fuse and >would > like to know if anyone has the phone # for Radio Systems >Tech or knows of a > good one that they have used. > > The phone number I have for Radio Systems Technology is 800-824-5978, but > that number dates back to 1976. As of a year ago they were still in > business. So if that nbr doesn't work, try directory assistance. They are > located in Grass Valley, CA. > > I used com and xponder antennas from Bob Archer in Torrance, CA. Phone 310 > 316 8796. I've heard good reports from others about his antennas, but have > yet to get my plane in the air to try them out. His xponder antenna is very > interesting. It is mounted on a flat circuit board, mounts vertically, and > can be installed at the end of the strake with nothing sticking into the > airstream - very neat! I don't know anything about his nav antenna though. > The guy seems very knowledgeable - before retiring he worked in one of the > aerospace companies and designed antennas for spacecraft! > > Stet Elliott > Perpetual Long-EZ builder > StetsonE@aol.com > > Date: Sun, 2 Jul 1995 07:34:24 -0700 From: johnw@daktel.com Subject: Re: Canard Antennae Welcome back!! Hope your beach time was enjoyed to the limit. I don't think that foam has any affect on the radio performance, but this is just a personal thought. John Williams Date: Sun, 2 Jul 1995 11:03:58 -0400 (EDT) From: Tech Support - Rick Subject: Re: Canard Antennae So long as there are no carbon fibers or graphite, and it is a standard cozy, The only thing you will have to worry about is the wiring and control linkages changing the signal. Otherwise, to the radio wave, the the glass and foam aren't there. Rick On Sun, 2 Jul 1995, Marc J. Zeitlin wrote: > People; > > While lying on the beach, soaking up the rays (and trying to not hear my > wife telling me about skin cancer :-) ) I was thinking about the bottom > skin layup I had finished on Wednesday, before leaving on vacation. It > struck me that I had COMPLETELY forgotten to install any antennae in the > canard. After 2 minutes of panic, I thought; hey, if the antenna's in > the bottom, the signal has to go through 3 layers of glass to get to it. > If I put the antenna under the top skin (assuming I can still keep the > skin VERY smooth) the signal will still have to go through the bottom 3 > layers of glass, but will also have to go through 2 - 3 inches of foam. > It's hard for me to imagine that this will make any difference at all, > but before I do it, I figured I'd ask if any of you with some E.E. > experience knew why this won't work. Thanks. > > (but mom, if I don't make mistakes, how will I LEARN?) :-). > > -- > >Marc J. Zeitlin E-Mail: marcz@an.hp.com Date: Sun, 2 Jul 1995 20:58:03 -0700 (PDT) From: Eric Westland Subject: Re: Canard Antennae Marc, I didn't put any antennas in the canard and the 4 I have on the wings are all on the top. I can't speak to the EE side of it, I just followed the RST writing I sent you. As to making it smooth, I generally embedded there antennas about 1/8" below the surface and then covered them over with micro which I let cure. I then sanded them down flush and later glassed over them. Seemed to work well although it took a little more time. Eric Date: Mon, 3 Jul 1995 09:52:45 -0400 From: SidLloyd@aol.com Subject: Re: Canard Antennae In a message dated 95-07-02 00:49:13 EDT, marcz@hpwarhw.an.hp.com writes: >If I put the antenna under the top skin (assuming I can still keep >the >skin VERY smooth) Installing my third antenna (winglet), I finally got it right. I carefully routed out a shallow channel for the copper foil using the dremel tool with the router attachement, 5-min epoxy'd the foil in, then filled the channel with dry micro. When partially cured, I did the skin layup. It came out perfectly smooth with no bumps. The other times I had used the adhesive backed foils, they either didn't adhere to the foam well and/or the glass had a slight bump on each edge of the foil (a chemical thing apparently.) Putting the dry micro over the foil and using 5-min epoxy fixed both problems. Sid Date: Mon, 3 Jul 1995 16:03:48 -0400 From: NBalog@aol.com Subject: Re: Canard Antennae Can't answer your question, but I just installed a (maybe I'll use it, maybe I won't, but if I need it it's there) NAV antenna on my fuselage bottom prior to glassing (this week, I'm on vacation). Let the micro set up overnight, and I hooked my ICOM A-22 handheld to it and I couldn't believe the reception I was getting on COM freqs; in my basement yet! I tried transmitting, but never got picked up before, and still didn't. -Norm Date: Tue, 4 Jul 1995 00:58:18 -0400 From: StetsonE@aol.com Subject: Re: Canard Antennae On 2 July, Marc Zeitlin wrote: >It struck me that I had COMPLETELY forgotten to install any >antennae in the canard. On my Long-EZ canard, I purposely installed the foil nav antenna on the lower exterior surface. I didn't want anything to impede foam to glass adhesion and create a situation where a delam could start. I'm probably being overly cautious but.... Anyway, installing the foil on the exterior surface is simple and easy. The foil antenna kit I used was from Radio System's Technology and had an adhesive backing. I stuck it on in the proper location on the lower external surface of the canard and glassed it over with one ply of that lightweight hobby store type fiberglass tape to hold it down. Don't worry about this method messing up your canard contour. The total *layup* is very thin. Once you get to the finishing stage, you'll realize that your *perfectly hotwired, sanded and glassed surfaces* aren't all that perfect. You're going to micro the surfaces and the antenna mounted externally will fair right in. Stet Elliott stetsone@aol.com Perpetual Long-EZ builder (10 years this August! But I've got excuses, real good excuses!) Date: Thu, 27 Jul 1995 16:16:34 -0400 From: KSPREUER@aol.com Subject: Re: Canard Antennae I work in the atenna business with Mc Donnell Douglas and have tried many antenna configurations out on my Cozy 3 place. I don't believe you will see any difference with the antenna inside either the top or bottom skin. The antenna patterns of interest for NAV are in the horizontal plane. So the radiation is really thru the L.E. However, even if it were thru the top and/or bottom skin the addition of the foam is insignificant at these frequencies. Date: Mon, 13 Nov 1995 12:01:38 -0600 From: Scott Mandel Subject: Chapter 6, Antenna X-Sun-Charset: US-ASCII I installed my nav antenna on Sunday. I used electrical sodder I bought at the local hardware store, and flux that I had from some plumbing work I did in the past. A friend of mine told me this flux was no good for the kind of work I'm doing. I always thought flux was flux. Do we have any electrical guys out there who can give me the real story? I don't totally trust this friends opinion, but who knows. He thought the flux I used would cause the connections to deteriorate. I can still remove the antenna, but once I skin the bottom it'll be pretty permanent. Date: 13 Nov 1995 12:21:27 -0600 From: "Bill Schertz" Subject: Re: Chapter 6, Antenna "Scott Mandel" Reply to: RE>Chapter 6, Antenna Scott Mandel writes I used electrical sodder I bought at the local hardware store, and flux that I had from some plumbing work I did in the past. -------------------------------------- Plumbing solder is usually of an acid type, which can cut through more oxide films on plumbing connections. This residual acid can cause corrosion of the electrial joint with time. At least that is what I have been told for soldering printed circuit boards. Electrical connections are usually soldered with "rosin-core" solder, which has the solder as a hollow tube, with the rosin-flux in the center. I would not recommend the use of the acid "plumbing" flux in this application. My $ .02 worth Bill Schertz Date: Mon, 13 Nov 1995 12:20:25 -0700 (MST) From: GROSSINGER ROY HELMUT Scott Mandel Subject: Re: Chapter 6, Antenna On 13 Nov 1995, Bill Schertz wrote: > Reply to: RE>Chapter 6, Antenna > > > Scott Mandel writes > I used electrical sodder I bought at the local hardware store, and flux that I > had from some plumbing work I did > in the past. > -------------------------------------- > Bill Schertz wrote: > Plumbing solder is usually of an acid type, which can cut through more oxide > films on plumbing connections. This residual acid can cause corrosion of the > electrial joint with time. At least that is what I have been told for > soldering printed circuit boards. > > Electrical connections are usually soldered with "rosin-core" solder, which > has the solder as a hollow tube, with the rosin-flux in the center. I would > not recommend the use of the acid "plumbing" flux in this application. You are right on about the pipe flux. I have had a simular copper conection get totaly corroded by acid which had followed the wire under the epoxy to total eat away all the metal. It was a real mess to redo. I would sugest you make the small investment and redo the connections using good old rosin-core solder. (It smells better too) You might also think about installing a spare antenna, may come in handy. Roy Grossinger Date: Mon, 13 Nov 1995 16:51:59 -0600 From: Scott Mandel Subject: Rosin Flux X-Sun-Charset: US-ASCII Thank You to everyone who responded to my flux question. I'm going to rip out that nasty antenna tonight. Stomp on it and curse it. :-) Then I'll go to Radio Shack and get fixed up with all the right stuff. I guess this teaches me a lesson for listening to the "experts" at Home Depot. By the way is Home Depot bashing allowed? :-) Oops, just kidding. (1.38.193.5/16.2) id AA06214; Mon, 13 Nov 1995 17:35:23 -0500 From: "Volk, Ray" Subject: Chapter 6, Antenna Date: Mon, 13 Nov 95 15:24:00 PST Encoding: 23 TEXT Scott writes >I installed my nav antenna on Sunday. I used electrical sodder I bought at >the local hardware store, and flux that I had from some plumbing work I did >in the past. A friend of mine told me this flux was no good for the kind of >work I'm doing. I always thought flux was flux. Scott You should only use solder with a rosin flux, as apposed to acid core flux. Electrical types normally use rosin core solder which is much less corrosive with time than acid core. Plumbers normally use acid core because it is stronger, cleans faster, and the residue can be thoroughly cleaned after soldering. After soldering be sure and clean off all residue so that it will not react with residual salts and produce corrosion. Hope this helps. Ray Volk rvolk@space.honeywell.com Date: Wed, 15 Nov 1995 17:43:54 -0500 From: Phillip.Johnson@Lockheed.on.ca (Phillip Johnson) Subject: Re: Chap 7, Fuselage Antenna The polar response for the V antenna has low sensitivity region in the direction of the apex of the V. Although you can get performance from the back of the forward facing V, the signal to noise ratio is lower so the accuracy is not so good flying from a VOR as it is flying to a VOR. If you are close to the VOR then the Signal to Noise ratio is high so it makes little difference. If the antenna is installed 'V apex forward' then, to capture the VOR signal, you will need to be closer to the VOR than if the 'V apex were pointing aft. The converse is true when flying FROM a VOR. Phillip Johnson ______________________________ Reply Separator _________________________________ Subject: Chap 7, Fuselage Antenna Author: Scott Mandel at smtp_gway Date: 15/11/95 7:37 AM People have relayed that they chopped through their fuselage antenna while installing the nose gear. I marked it out and saw that it would be very close, so I reversed the angle (V opens backwards). A fellow Cozy builder (not on the Net so I'll leave his name out) thought this might affect my Nav reception. I said, "Hey I never got any worse reception flying "FROM" a VOR as oppose to "TO" a VOR. He commented that all the airplanes he's ever seen face the antenna forward, so there must be a good reason. I've flown C-150s and they fly backwards (in strong winds) and it doesn't affect their reception :-). Seriously, Do any of you wiz-bang electrical guys out there know if it makes any difference if the Nav faces forward or backward. Date: Thu, 16 Nov 95 09:11:34 EST From: "Wilhelmson, Jack" Encoding: 20 Text Subject: Re: Chap 7, Fuselage Antenna Scott: It does not make any difference. Electro Magnetic Wave propogation theory states that the recieving antennas should be polarized(oriented) the same as the transmitting antennas. The VOR signals are set for a horizontal antenna polorization and COM signals are set for vertical. My own experience with dipole antennas embedded in composite structures is that the VOR attenna works best if it kept away from other metal parts(especially the ends of the V) The under side of the canard in the center with the V center at the trailing edge worked for me. Transmit\Recieve Dipole antennas as described in Sport Aviation for composites are very directional and in most cases cannot be vertically polarized. My experience with these is that they do not perform well when compared to a properly installed vertical bent whip with a 8 in square ground plane. A directional com antenna is a frustrating thing to contend with in a high traffic IFR situation. I have been there. Date: 13 Dec 95 16:10:53 EST From: Chuck <75501.356@compuserve.com> Subject: Nav antenna as ELT (continued) Looked it up, just cause I wanted to see if I was right....and of course I wasn't! According to Jim Weir's articles, the length for the copper foil tapes for each leg are listed as follows Com - 20.3", Nav - 22.8", and Marker - 34.3". To figure the length in inches use 2578/F, where F is frequency in MegaHertz. At any rate, the nav antenna length is about 1.58" too long (using the average/ middle frequency for the nav band), not just 1/8", as I indicated previously. Sorry, if I cause any problems here for anyone. I still feel that the SWR is low enough for a good signal from an ELT. I do not recall my measured readings for this, but can only attest to satisfactory results with the ELT signal. Date: Wed, 13 Dec 1995 17:11:51 -0600 From: Tom Barclay Subject: Antennae; internal vs. external The older I get, the more I learn that I don't understand a lot; so please cure my ignorance. If the built-in antenna is so hard to get installed correctly, why not use a common boomerang-shaped external antenna, or one of the other vestigial-fin shapes? Is it a problem with the composite airframe? I look forward to any and all responses at <>. Extra no-points awarded for creativity and originality in bending the laws of RF and physics. From: Marc Zeitlin Date: Wed, 13 Dec 95 19:06:37 EST Subject: Antennae; internal vs. external (fwd) Tom Barclay asks: >............... If the built-in antenna is so hard to >get installed correctly, why not use a common boomerang-shaped external >antenna, or one of the other vestigial-fin shapes? There are two reasons for the built-in antennae: 1) It's CHEAP - $5 to $10 per antennae 2) NO DRAG (as in: NONE) External antennae have neither of these properties :-). Plus, they look stupid. This is a classic case of getting something for nothing, and saving money doing it. It's NOT difficult to install one and have it work correctly - the plans just don't tell you exactly where to put it (in the fuselage bottom) so that it doesn't interfere with the nosewheel or the landing brake. You have to do a bit of searching in later chapters to figure out how not to have these problems. >Extra no-points awarded for creativity and originality in bending >the laws of RF and physics. Ummm, radio waves (as all sentient beings) like cool stuff? -- Marc J. Zeitlin Email: marcz@an.hp.com From: "Craig R. Bowers" Subject: RE: nav antenna Date: Thu, 14 Dec 1995 13:42:00 -0800 John Wilemski wrote: >I don't know if anyone had the same problem but here goes: I used the copper >foil tape on the fuselage bottom for my nav antenna and when I went to cut >out the area for my nosewheel I discovered that the tape was a little too far >forward. I should have applied the tape farther aft so that the "V" would >clear the nosewheel..... >Do the think the original foil tape just in front of the operating antenna >will affect >antenna performance at all? > > / / > / / < 1st ant (in way of nosewheel cutout) > \ \ > \ \ Yes, the first ant. will cause something to happen. Although I'm not too sure if the something would be good or bad! First, you should go outside and look at your TV ant. Unless you have cable, then you will need to drive around until you do see an ant. See all of the elements of the ant.? They are called directors and reflectors. When the ant. is pointed in the proper direction they improve the dB gain of the ant. This has the affect of making the ant. much more directional. This in turn makes the ant. rotor makers very happy, and rich! If the ant. is pointed away from the transmitter (VOR site) it may be posable to have a negitive dB gain, making the signal unusable. Whether the first ant. will act as a director or reflector depends on many things. But my best guess is that the old and new NAV ants. will not work as well as a NAV ant. moved farther from the old one. I do hope that this will help! It has been a long time since I worked with RF. And as my seven year old sons like to tell my, "Daddy, you don't know everything"! Any other comments will be taken well. I do boo, boo at times!:-) Craig R. Bowers craigb@gargamel.ptw.com Soon to be Cozy builder. You've read the mail, now see the home page!!! http://www.ptw.com/~craigbCraig R. Bowers E-Mail: craigb@gargamel.ptw.com From: "Rob Cherney" Organization: Ellicott City, Maryland Date: Fri, 15 Dec 1995 00:17:28 -0400 Subject: Re: nav antenna Hi gang: I think a little bit of misinformation exists re: the usage and placement of foil tape antennas. If I present some information that most of you already know, please bear with me; one or two people might be receiving the benefit of some new data. The comm antenna needs to be vertically oriented as this is the proper polarization. The best place for these are in the winglets. When vertically oriented, they *are not very directional*. Think of the radiation pattern as a doughnut sitting in the horizontal plane. Most of the radiated energy will be directed at the horizon. The nav antennas need to be horizontally polarized. The best place for these are span-wise along the wings or canard, since the energy must be directed fore or aft. The useful part of the radiation pattern will look like a figure eight, with the lobes fore and aft. A marker beacon antenna needs to be horizontally polarized also, except this antenna needs to run along the length of the fuselage. Also, this antenna needs to be close to 6 feet in length since the receive frequency is at 75 MHz. The foil antennas designed by Jim Weir are common dipoles. The correct lengths for these antennas have been stated in a previous post. There is little or no improvement that can be realized within the confines of our wings, winglets, canard, or fuselage without the sacrifice of performance in one direction or another. The bottom line is that you can pay more, but you can't buy an antenna that performs better than the one that you can make. The last fraction of a dB that one might obtain with another design will not be noticed in practice. The claims in the ads to the contrary are science fiction (notice that there are no performance figures stated in the ads). Rob- (Have a cool yule) +--------------------------------------------------------+ |Robert Cherney Home Phone: (410)465-5598 | |Ellicott City, Maryland e-mail: cherney@clark.net | +--------------------------------------------------------+ Date: Fri, 15 Dec 1995 01:02:28 -0500 From: KSPREUER@aol.com Subject: Nav Antennas My $.02 is that the nav antenna in the belly could be put in slanting the opposite way. Put the apex up front near the nose wheel and point the tips rearward. If it crosses your old antenna at one point on each side that shouldn't hurt. May a couple of the antenna experts that have written can comment on that. One ply of glass is more than enough. I put one on the belly of my Cozy for 7 years only covered with paint. In regard to the obsolesces of the VOR system. That may be so but these antennas are so cheap I'm putting in the full suite just in case. About the directionality of the Nav antennas: They are directional. The more the dipoles are in a straight line, the more directional they are. It helps in the canard to make as much of a V as possible. In the belly there is plenty of more to V so I doubt if that one is very directional. Date: Fri, 15 Dec 1995 09:34:10 -0500 From: JHocut@aol.com Subject: Re: nav antenna Rob Cherney's post on antennas was right on the mark. After thinking about this for a little while, I can think of one tidbit to add. The location for the nav antenna in the belly places it real close to lots of metal (nosewheel, etc.), therefore this location is a big compromise. Like Marc said, there's plenty of room for antennas in the wing, which would be much cleaner RF-wise for the nav antenna. So, I'll be putting my nav antenna in the wing, and maybe one in the other wing as a spare. If I get real motivated I may even work on some new ideas for antennas (well, new for aviation use anyway) - and don't worry, I won't make any fantastic claims until I've done A vs. B comparisons etc. Jim Hocut jhocut@aol.com Date: Fri, 15 Dec 95 10:31:48 EST From: MISTER@neesnet.com Subject: Re[2]: nav antenna Another aspect of this antena business is the ELT antenna. I bought an ACK ELT that has this hokey little antenna for mounting on the outside of spam cans. Couldn't really mount it inside because it needs a pretty large ground plane. I certainly didn't want to mess up the outside of my Cozy with it. I talked to Jim Weir at Oshkosh one year and asked him for suggestions. He said to just put a foil tape dipole antenna inside the fuselage. I did that by making a dipole (more like a vee) on the aft side of the front seat back. I think it will work fine (actually I hope I never need it). Since the ELT is mounted on the rear arm rest the feedline is really short. My $.02 Bob Misterka N342RM