[amsat-bb] Re: Antenna discussions
Agree !! Along those lines, before I put up my Kenpro az/el rotor, I plan on testing various locations using my Elk with a fixed el but on a small rat shack rotor for az. I have seen here recommendations for 15 deg and some for 30 deg fixed el. Thus there seems to be 2 schools of thought on this. Is there any compelling argument for one or the other? I'm almost inclined to split the diff at +-22 deg. (most passes for me are N/S and to the E - not so good to W Any thoughts appreciated 73, Ted, K7TRK -Original Message- From: amsat-bb-boun...@amsat.org [mailto:amsat-bb-boun...@amsat.org] On Behalf Of gw1...@aol.com Sent: Saturday, March 19, 2011 2:36 AM To: amsat-bb@amsat.org Subject: [amsat-bb] Re: Antenna discussions Hi all, Regarding the discussions on antennas - I am not into any debate about the pro's and con's, but would just like to encourage anyone to just have a go. Sure the argument will always prevail perhaps under the Must do Better comment and I am sure that one can always improve or progress with experimenting - ( AMATEUR RADIO ) ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: Antenna discussions
The actual fixed elevation on the AZ rotor is determined by the beam width of the yagi antenna used. If at all possible, all the calculations based on the average pass elevation is near 30 degrees. If you believe that you will use lower passes, say if the beam width is 25 degrees, putting it fixed at about 20degrees gives you the split of + - 12.5 degrees. It IS a tradeoff. The higher the gain of the Yagi, the lower the beam width. Good Luck... Dee, NB2F -Original Message- From: amsat-bb-boun...@amsat.org [mailto:amsat-bb-boun...@amsat.org] On Behalf Of Ted Sent: Thursday, March 24, 2011 2:02 PM To: gw1...@aol.com; amsat-bb@amsat.org Subject: [amsat-bb] Re: Antenna discussions Agree !! Along those lines, before I put up my Kenpro az/el rotor, I plan on testing various locations using my Elk with a fixed el but on a small rat shack rotor for az. I have seen here recommendations for 15 deg and some for 30 deg fixed el. Thus there seems to be 2 schools of thought on this. Is there any compelling argument for one or the other? I'm almost inclined to split the diff at +-22 deg. (most passes for me are N/S and to the E - not so good to W Any thoughts appreciated 73, Ted, K7TRK -Original Message- From: amsat-bb-boun...@amsat.org [mailto:amsat-bb-boun...@amsat.org] On Behalf Of gw1...@aol.com Sent: Saturday, March 19, 2011 2:36 AM To: amsat-bb@amsat.org Subject: [amsat-bb] Re: Antenna discussions Hi all, Regarding the discussions on antennas - I am not into any debate about the pro's and con's, but would just like to encourage anyone to just have a go. Sure the argument will always prevail perhaps under the Must do Better comment and I am sure that one can always improve or progress with experimenting - ( AMATEUR RADIO ) ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: Antenna discussions
I agree with Dee, but I'll add my opinion. The fixed elevation option is a good approach to reduce your costs. If you are going to fix the elevation, do *not* use a very high gain antenna with a narrow beam width. You are better off with a moderate gain antenna (for example, the Elk or 4-7 element vertical or 2x7 circularly polarized) so that you have a wider beam width. 73, Steve N9IP -- Steve Belter (s...@wintek.com) My Desk: 765-269-8521 Indiana Dataline Corp Billing: 765-269-8502 427 N 6th Street, Suite C Wintek Internet: 765-269-8503 Lafayette, IN 47901-2211Wintek Consulting: 765-269-8504 -Original Message- From: amsat-bb-boun...@amsat.org [mailto:amsat-bb- boun...@amsat.org] On Behalf Of Dee Sent: Thursday, March 24, 2011 2:18 PM To: 'Ted'; gw1...@aol.com; amsat-bb@amsat.org Subject: [amsat-bb] Re: Antenna discussions The actual fixed elevation on the AZ rotor is determined by the beam width of the yagi antenna used. If at all possible, all the calculations based on the average pass elevation is near 30 degrees. If you believe that you will use lower passes, say if the beam width is 25 degrees, putting it fixed at about 20degrees gives you the split of + - 12.5 degrees. It IS a tradeoff. The higher the gain of the Yagi, the lower the beam width. Good Luck... Dee, NB2F -Original Message- From: amsat-bb-boun...@amsat.org [mailto:amsat-bb- boun...@amsat.org] On Behalf Of Ted Sent: Thursday, March 24, 2011 2:02 PM To: gw1...@aol.com; amsat-bb@amsat.org Subject: [amsat-bb] Re: Antenna discussions Agree !! Along those lines, before I put up my Kenpro az/el rotor, I plan on testing various locations using my Elk with a fixed el but on a small rat shack rotor for az. I have seen here recommendations for 15 deg and some for 30 deg fixed el. Thus there seems to be 2 schools of thought on this. Is there any compelling argument for one or the other? I'm almost inclined to split the diff at +-22 deg. (most passes for me are N/S and to the E - not so good to W Any thoughts appreciated 73, Ted, K7TRK -Original Message- From: amsat-bb-boun...@amsat.org [mailto:amsat-bb- boun...@amsat.org] On Behalf Of gw1...@aol.com Sent: Saturday, March 19, 2011 2:36 AM To: amsat-bb@amsat.org Subject: [amsat-bb] Re: Antenna discussions Hi all, Regarding the discussions on antennas - I am not into any debate about the pro's and con's, but would just like to encourage anyone to just have a go. Sure the argument will always prevail perhaps under the Must do Better comment and I am sure that one can always improve or progress with experimenting - ( AMATEUR RADIO ) ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: Antenna discussions
I really forget was it the radio or the antenna that came first? ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: Antenna discussions
Ted, How about a 3rd school of thought? If you have a clear view of the horizon, I recommend you point the antenna(s) directly at the antenna (0 degrees elevation). That is the point in a satellite's path across the sky where you have the greatest range (distance between you and the satellite) and the bi-directional greatest path loss (not counting any ground gain you will experience if you have horizontal or CP antennas). As the satellite rises in elevation, range and path loss both decrease and you need less gain to overcome noise: a moderate-beamwidth antenna with a gain of 8-10 dBi will match this nicely. A LEO satellite spends the majority of it's visible time below 30 degrees and the pass time above 60 degrees is almost negligible. If you can't hear the satellite at the horizon with this setup, then you can raise the antenna's angle and listen when the satellite is closer (higher elevation), but you will greatly reduce the available time/footprint and your number of contacts. 73, Jerry, K5OE -Original Message- Agree !! Along those lines, before I put up my Kenpro az/el rotor, I plan on testing various locations using my Elk with a fixed el but on a small rat shack rotor for az. I have seen here recommendations for 15 deg and some for 30 deg fixed el. Thus there seems to be 2 schools of thought on this. Is there any compelling argument for one or the other? I'm almost inclined to split the diff at +-22 deg. (most passes for me are N/S and to the E - not so good to W Any thoughts appreciated 73, Ted, K7TRK ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: Antenna discussions,
Back in the goode olde dayes, if we didn't have an elevation rotor we would put a horizontally polarized yagi at a fixed 30 degree elevation. That allowed working the satellites for at least 95 percent of a pass and often for a complete pass. I did this for quite a while before I obtained a rotor for controlling the elevation. Glen, K9STH AMSAT 239 / LM 463 Website: http://k9sth.com --- On Sat, 3/19/11, Ellis Foley wa1...@yahoo.com wrote: Like so many before me posted, I have had gud success with linear polarized antennas. I have been using stacked 11 el vertically pol, on 2m since 1974, and recently went to 2x20 el on 432-435 mhz horizontally pol, stacked in between the vertical 2m ant, With great success. as most of you that posted have worked me on them. fixed elevation also. from 0-30 deg. off the horizons I do very well, little spotty over head, although I do need some pre-amps to work the fm birds. but I think thats more of an radio problelm than antenna. my 2 cents worth! Pics of my ant. on my QRZ spot,along with the Beast my new HB 9el 36ft boom 6m ant. ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
