[amsat-bb] Strong winds in São Paulo
Hello, Friend in São Paulo make a movie from his antenas under strong winds. http://www.youtube.com/watch?v=lZv3i57QS0E -- 73 Fabiano Moser CR7/PY5RX ARISS-PORTUGAL (Amateur Radio on the International Space Station) Representative at Teleconference and Portugal Telebridge Coordinator. AMRAD/AMSAT-CT http://www.amrad.pt/ariss.php There is no great talent without great will. (Honoré de Balzac) ___ Sent via amsat...@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: quadrafilar helix for 70cm- ambiguous design specs
Hi Frank, KB1QZH The best starting point is the original article of the inventor of QHA i.e Walter Maxell, W2DU In a separate email I have attached the above fundamental article. 73 de i8CVS Domenico - Original Message - From: Franklyn A. Ballentine, jr art.ballent...@gmail.com To: i8cvs domenico.i8...@tin.it Cc: AMSAT-BB amsat-bb@amsat.org Sent: Tuesday, September 29, 2009 6:45 PM Subject: Re: [amsat-bb] Re: quadrafilar helix for 70cm- ambiguous design specs I have a question along the same line. Is the QHA in the ARRL Satellite Handbook \ Antenna handbook, a good starting place? Thanks, Frank B. KB1QZH On Tue, Sep 29, 2009 at 11:17 AM, i8cvs domenico.i8...@tin.it wrote: - Original Message - From: Tim Goodrich t...@timgoodrich.net To: amsat-bb@amsat.org Sent: Monday, September 28, 2009 9:45 PM Subject: [amsat-bb] quadrafilar helix for 70cm- ambiguous design specs Hi All, The house I just bought precludes me from even using my arrow inside as there must be something un-RF friendly in the walls. Therefore, I was looking for a roof antenna and the October QST article on the QFH inspired me to build one. However, after doing some research, I have come up with two sets of design specs and I'm unsure which one is correct. I converted everything from you're the 146Mhz QST model to 436Mhz. However, when I plug that info into http://www.jcoppens.com/ant/qfh/calc.en.php The values it puts out are different in the compensated length field. The only difference is this model calculates for a full turn as opposed to a half turn, but the lengths shouldn't be as different as it says. Under the QST model, I get a wavelength of 688mm, but under the website's model, it gives me a compensated wavelength of 729mm. The values I used to calculate are: 436 1 1 15 2 .23 Can anyone tell me which specs to use and/or explain this compensated wavelength issue? Thank you, Tim KI6VBY Hi Tim, KI6VBY Read please the book REFLECTION Transmission Lines and Antennas by M. Walter Maxwell, W2DU Chapter 22 The Quadrifilar Helix Antenna pages 22-1 to 22-23 and also Experimental Investigation of Quadrifilar Helix Antennas for 2400 MHz The AMSAT Journal May/June 2004 In a separate email I have sent to you both articles as an attachement. 73 de i8CVS Domenico ___ Sent via amsat...@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...@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] AMSAT Symposium
This is a reminder that the AMSAT Symposium is quickly approaching. It takes place next weekend (9-11 OCT) at the BWI Sheraton and you're invited! This Symposium marks the 40th Anniversary of AMSAT and we'll be celebrating this significant milestone along with looking forward to the next 40 years. AMSAT members who are registered for the Symposium are invited to a 'birthday party' for AMSAT Friday evening (including a birthday cake). In addition, Symposium attendees will also receive a 40th Anniversary History of AMSAT written/edited by Bill Tynan, W3XO in their registration packets. Many of us don't know the 'story of AMSAT', and thanks to the work of Bill Tynan, Dick Daniels, Keith Baker and others, we've focused this year on telling AMSAT's story through their articles in the AMSAT Journal. Bill's new book provides significantly more detail as well as brings the reader right up to the current year. It makes for fun reading and gives recognition to the significant achievements over the past 40 years! This year's AMSAT Proceedings has a wide assortment of papers and this year's presentations will be both interesting and informative. Dan Schultz, N8FGV is finalizing the Proceedings as this is written and attendees will be in position to hear the presentations, discuss the papers with the authors, and gain some insight into the future direction of AMSAT's satellite program. The Saturday evening Banquet will feature Martin Collins, a curator at the Smithsonian Air Space Museum. The title of his talk is Making the Space Age: The First Fifty Years. A reminder that that the AMSAT BOD meeting takes place Thursday, 8 OCT and Friday morning, 9 OCT. This is an open meeting, though the BOD does go into closed session briefly on Friday morning. In addition the AMSAT Annual Meeting takes place Saturday afternoon 1530-1700 EDT. We expect to have the Annual Meeting 'online' via Echolink. I anticipate that both the Symposium and the Annual Meeting will be an opportunity to highlight some of the significant accomplishments that have taken place over the last 12 months plus give some perspective on the future direction of AMSAT. Please consider joining us to celebrate a significant milestone for AMSAT and build the foundation for the next 40 years! You may register online at the AMSAT Store: http://www.amsat-na.com/store2/SymposiumReg2009.php . 73, Barry A. Baines, WD4ASW President-AMSAT ___ Sent via amsat...@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: need mike for Yaesu FT530
Hi folks, tnx for all the help, i now have one, it's the MFJ286 speaker/mic. model which works well with the FT530. 73 de VE6ITV Scott ___ Sent via amsat...@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] Kursk experiment on ARISSAT-1
It's great to see the diagrams of ARISSAT-1 up on the web site: congratulations to KF4KSS and everyone who contributed. Can anyone describe the nature of the experiment from Kursk University that is going to be included in the satellite? 73, Bruce VE9QRP ___ Sent via amsat...@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] College Satellite nights, Thursday night
Don't forget to work the Thursday evening passes and listen for, and work, college club stations. On AO-51 we'll be on the QRP transponder. AO-7 should be in mode B that evening. HAMSAT has been little used and is a great bird, with some nice passes that evening. Activity will be centered on passes starting Thursday Oct. 1st 22:00 UTC through 05:00 UTC. U of Kansas (K0KU), Stanford (W6YX), UF Gators (W4DFU) and Rochester IT (K2GXT) have already confirmed they will be on. Other clubs have been active during past events including U Michigan, Michigan State U, U Kentucky. U Arkansas, Naval Academy, and others. Please give college station priority on the QRP transponder on AO-51 that evening and let them work everyone they can. No good deed should go unrewarded.look for an award certificate program in the near future for working college club stations on satellite. We have asked the clubs to QSL those that they work and appreciate your patience in letting the club stations have priority for the evening. Jay, AA4FL ___ Sent via amsat...@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] Cute 1.7 Re Entry Competition
Hi folks, Thanks for the entries so far. It has been pointed out that I didn't allow much time, so the closing date is now one day later, midnight October 1st To enter this fun competition send me your best estimate for the re-entry date and time for Cute 1.7 Object 28941 Spacetrack suggests October 10th but I think it will be several days later. The prize for the closest prediction is a 2.4GHz patch antenna kit as shown on the Amsat-UK shop page under hardware. 73 John G7HIA ___ Sent via amsat...@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: quadrafilar helix for 70cm- ambiguous design specs
The most comprehensive info on QFH antennas is the Microwave Journal December 1970 Pgs 49-54 By CC Kilgus. Art, KC6UQH -Original Message- From: amsat-bb-boun...@amsat.org [mailto:amsat-bb-boun...@amsat.org] On Behalf Of i8cvs Sent: Wednesday, September 30, 2009 5:35 AM To: AMSAT-BB; Franklyn A. Ballentine, jr Subject: [amsat-bb] Re: quadrafilar helix for 70cm- ambiguous design specs Hi Frank, KB1QZH The best starting point is the original article of the inventor of QHA i.e Walter Maxell, W2DU In a separate email I have attached the above fundamental article. 73 de i8CVS Domenico - Original Message - From: Franklyn A. Ballentine, jr art.ballent...@gmail.com To: i8cvs domenico.i8...@tin.it Cc: AMSAT-BB amsat-bb@amsat.org Sent: Tuesday, September 29, 2009 6:45 PM Subject: Re: [amsat-bb] Re: quadrafilar helix for 70cm- ambiguous design specs I have a question along the same line. Is the QHA in the ARRL Satellite Handbook \ Antenna handbook, a good starting place? Thanks, Frank B. KB1QZH On Tue, Sep 29, 2009 at 11:17 AM, i8cvs domenico.i8...@tin.it wrote: - Original Message - From: Tim Goodrich t...@timgoodrich.net To: amsat-bb@amsat.org Sent: Monday, September 28, 2009 9:45 PM Subject: [amsat-bb] quadrafilar helix for 70cm- ambiguous design specs Hi All, The house I just bought precludes me from even using my arrow inside as there must be something un-RF friendly in the walls. Therefore, I was looking for a roof antenna and the October QST article on the QFH inspired me to build one. However, after doing some research, I have come up with two sets of design specs and I'm unsure which one is correct. I converted everything from you're the 146Mhz QST model to 436Mhz. However, when I plug that info into http://www.jcoppens.com/ant/qfh/calc.en.php The values it puts out are different in the compensated length field. The only difference is this model calculates for a full turn as opposed to a half turn, but the lengths shouldn't be as different as it says. Under the QST model, I get a wavelength of 688mm, but under the website's model, it gives me a compensated wavelength of 729mm. The values I used to calculate are: 436 1 1 15 2 .23 Can anyone tell me which specs to use and/or explain this compensated wavelength issue? Thank you, Tim KI6VBY Hi Tim, KI6VBY Read please the book REFLECTION Transmission Lines and Antennas by M. Walter Maxwell, W2DU Chapter 22 The Quadrifilar Helix Antenna pages 22-1 to 22-23 and also Experimental Investigation of Quadrifilar Helix Antennas for 2400 MHz The AMSAT Journal May/June 2004 In a separate email I have sent to you both articles as an attachement. 73 de i8CVS Domenico ___ Sent via amsat...@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...@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 __ Information from ESET NOD32 Antivirus, version of virus signature database 4468 (20090929) __ The message was checked by ESET NOD32 Antivirus. http://www.eset.com __ Information from ESET NOD32 Antivirus, version of virus signature database 4471 (20090930) __ The message was checked by ESET NOD32 Antivirus. http://www.eset.com ___ Sent via amsat...@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
