---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Thu 02/09/06: 8 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 03:10 PM - Icom A200-Help! (Jerry2DT@aol.com) 2. 03:33 PM - antennas (bob noffs) 3. 03:46 PM - Re: antennas (Robert L. Nuckolls, III) 4. 03:46 PM - Re: Icom A200-Help! (Robert L. Nuckolls, III) 5. 04:30 PM - Re: antennas (Brian Lloyd) 6. 06:11 PM - Re: antennas (Robert L. Nuckolls, III) 7. 07:56 PM - Re: antennas (Dave Morris \) 8. 11:33 PM - Re: Icom A200-Help! (Mickey Coggins) ________________________________ Message 1 _____________________________________ Time: 03:10:37 PM PST US From: Jerry2DT@aol.com Subject: AeroElectric-List: Icom A200-Help! --> AeroElectric-List message posted by: Jerry2DT@aol.com Listers, This question has been asked before by others, but replies are unclear. The good folks at Icom have put an insufficient (IMO) "wiring diagram" in their one sheet fold-out instructions. This is not like the ones we see on this list, so they must think we are incapable of reading a "real" one. Now that I've vented... Has anyone out there made a genuine one for this radio that I can beg, borrow, steal? My setup is with two of these radios, but with no audio panel. This might have been a mistake, trying to save weight, time, panel space, and $$$... Jerry Cochran Wilsonville, OR ________________________________ Message 2 _____________________________________ Time: 03:33:25 PM PST US From: "bob noffs" Subject: AeroElectric-List: antennas --> AeroElectric-List message posted by: "bob noffs" hi all, I have several antennas to install. My elt requires a ground plane. Tim at b and c was very helpful with my questions but i question leads to 5 more. Is there any way around a ground plane for the elt? If not, any suggestions on how to make it in my wood/cloth fuselage? At first i thought numerous strips of thin copper way the way to go but that looks like just more fasteners. Can a very thin sheet be laid down in the fuse. bottom? It wouldnt exactly be flat with all the woodworking to go around. Also, my dipole comm must be vertical. No more than 45 deg slant. is 30 deg vastly better than 45 deg and is 15 deg vastly better than 30 deg. Are these slanted antennas going to noticeably going to affect transmission/ reception that much anyway? Anyone want to volunteer a phone number to me off list? i have more questions every time i get one answered. Thanks in advance, bob noffs ________________________________ Message 3 _____________________________________ Time: 03:46:48 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: antennas --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 05:30 PM 2/9/2006 -0600, you wrote: >--> AeroElectric-List message posted by: "bob noffs" > >hi all, > I have several antennas to install. My elt requires a ground plane. Tim > at b and c was very helpful with my questions but i question leads to 5 > more. Is there any way around a ground plane for the elt? If not, any > suggestions on how to make it in my wood/cloth fuselage? At first i > thought numerous strips of thin copper way the way to go but that looks > like just more fasteners. Can a very thin sheet be laid down in the fuse. > bottom? It wouldnt exactly be flat with all the woodworking to go around. If it's wood and fabric, I'd go with a vertical dipole wrapped around the inside surface of the fuselage. Perhaps on side opposite your comm dipole cited below and separated some fore/aft as well . . . > Also, my dipole comm must be vertical. No more than 45 deg slant. is 30 > deg vastly better than 45 deg and is 15 deg vastly better than 30 deg. > Are these slanted antennas going to noticeably going to affect > transmission/ reception that much anyway? No . . . the lion's share of antenna performance happens in the first 25% of length each side of center (about 5") meaning that things you do with the last 15" per side are not terribly critical. Get as much of the center section for both antennas as vertical as practical, then wrap the ends around the inside surface of the fuselage. They'll drop in center frequency as you "fold" them so you MIGHT want to check them with an SWR/Antenna analyzer and trim them for optimum. > Anyone want to volunteer a phone number to me off list? i have more > questions every time i get one answered. Let's do it on the list. If your questions are worth asking, then they're worth sharing too. Bob . . . ________________________________ Message 4 _____________________________________ Time: 03:46:52 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Icom A200-Help! --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 06:01 PM 2/9/2006 -0500, you wrote: >--> AeroElectric-List message posted by: Jerry2DT@aol.com > >Listers, > >This question has been asked before by others, but replies are unclear. The >good folks at Icom have put an insufficient (IMO) "wiring diagram" in their >one sheet fold-out instructions. This is not like the ones we see on this >list, so they must think we are incapable of reading a "real" one. > >Now that I've vented... Has anyone out there made a genuine one for this >radio that I can beg, borrow, steal? My setup is with two of these >radios, but >with no audio panel. >This might have been a mistake, trying to save weight, time, panel space, >and $$$... Got a 'net address for their published schematic? Bob . . . ________________________________ Message 5 _____________________________________ Time: 04:30:53 PM PST US From: Brian Lloyd Subject: Re: AeroElectric-List: antennas --> AeroElectric-List message posted by: Brian Lloyd bob noffs wrote: > Is there any way around a ground plane for the elt? No. > If not, any suggestions on how to make it in my wood/cloth fuselage? Most anything will do. You want some strips of copper or wire that are the same length as the ELT antenna, i.e. 1/4 wave at 121.5 MHz (about 25" or so). A flat piece of metal 25" in radius or larger would work. And it may be oddly shaped. > Can a very thin sheet be laid down in the fuse. bottom? Certainly. That would be fine. > It wouldnt exactly be flat with all the woodworking to go around. That doesn't matter. > Also, my dipole comm must be vertical. No more than 45 deg slant. is 30 deg vastly better than 45 deg and is 15 deg vastly better than 30 deg. The closer you are to vertical, the better it will work but anything will work after a fashion, even horizontal. Just try to get it as vertical as possible. > Are these slanted antennas going to noticeably going to affect transmission/ reception that much anyway? Odds are, no, you won't notice the difference. > Anyone want to volunteer a phone number to me off list? i have more questions every time i get one answered. If I have time I would answer your questions. -- Brian Lloyd 361 Catterline Way brian-yak at lloyd dot com Folsom, CA 95630 +1.916.367.2131 (voice) +1.270.912.0788 (fax) I fly because it releases my mind from the tyranny of petty things . . . - Antoine de Saint-Exupery ________________________________ Message 6 _____________________________________ Time: 06:11:40 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: antennas --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" Guess I forgot to ask if you had a dual freq ELT . . . I guess all the new ones are. In this case, the ground plane under a stock antenna is necessary. But since it's a dual freq, one might argue that two sets of radials would be good . . . one set tuned for 121.5 (24") and another set optimized for 406 (7.3"). Hmmm . . . maybe a 7.3" radius piece of copper foil with a few 20" legs soldered to the edge. The single dipole I suggested would not be suited for dual frequency use (although one COULD be crafted . . . it would probably be more trouble than it's worth). Bob . . . At 05:30 PM 2/9/2006 -0600, you wrote: >--> AeroElectric-List message posted by: "bob noffs" > >hi all, > I have several antennas to install. My elt requires a ground plane. Tim > at b and c was very helpful with my questions but i question leads to 5 > more. Is there any way around a ground plane for the elt? If not, any > suggestions on how to make it in my wood/cloth fuselage? At first i > thought numerous strips of thin copper way the way to go but that looks > like just more fasteners. Can a very thin sheet be laid down in the fuse. > bottom? It wouldnt exactly be flat with all the woodworking to go around. If it's wood and fabric, I'd go with a vertical dipole wrapped around the inside surface of the fuselage. Perhaps on side opposite your comm dipole cited below and separated some fore/aft as well . . . > Also, my dipole comm must be vertical. No more than 45 deg slant. is 30 > deg vastly better than 45 deg and is 15 deg vastly better than 30 deg. > Are these slanted antennas going to noticeably going to affect > transmission/ reception that much anyway? No . . . the lion's share of antenna performance happens in the first 25% of length each side of center (about 5") meaning that things you do with the last 15" per side are not terribly critical. Get as much of the center section for both antennas as vertical as practical, then wrap the ends around the inside surface of the fuselage. They'll drop in center frequency as you "fold" them so you MIGHT want to check them with an SWR/Antenna analyzer and trim them for optimum. > Anyone want to volunteer a phone number to me off list? i have more > questions every time i get one answered. Let's do it on the list. If your questions are worth asking, then they're worth sharing too. Bob . . . ________________________________ Message 7 _____________________________________ Time: 07:56:25 PM PST US From: "Dave Morris \"BigD\"" Subject: Re: AeroElectric-List: antennas --> AeroElectric-List message posted by: "Dave Morris \"BigD\"" In theory, the amount of loss varies as the cosine of the angle difference between the transmitting and receiving antennas. At a 45 degree angle, you lose 3dB, which is somewhat noticeable, because it is actually 1/2 of the power lost. At 90 degrees, it is over 20dB loss, which is substantial. In practice, the signals bounce around and may not arrive at your antenna perfectly vertically polarized to begin with, but it doesn't hurt to make it as close to vertical as possible. The problems will mainly show up when you're a long way away from the ground station. When you're close, it won't make much difference. Dave Morris At 05:30 PM 2/9/2006, you wrote: >--> AeroElectric-List message posted by: "bob noffs" > > Also, my dipole comm must be vertical. No more than 45 deg slant. is 30 > deg vastly better than 45 deg and is 15 deg vastly better than 30 deg. > Are these slanted antennas going to noticeably going to affect > transmission/ reception that much anyway? ________________________________ Message 8 _____________________________________ Time: 11:33:37 PM PST US From: Mickey Coggins Subject: Re: AeroElectric-List: Icom A200-Help! --> AeroElectric-List message posted by: Mickey Coggins > Got a 'net address for their published schematic? I've scanned one here: http://rv8.ch/files/Icom%20IC-A200%20Installation%20Instructions.pdf Basically you want page 5. Sorry about the huge file size for those of you not on broadband. It's about 6MB. Mickey -- Mickey Coggins http://www.rv8.ch/ #82007 finishing