[amsat-bb] Re: PIC rotator control
On Wed, 2009-10-14 at 07:20 +1000, Andrew Rich wrote: Thanks Yes a small 10 inch laptop could do the work, predict would be used and frequent kep updates I'm looking at using a mini2440 board for just such a thing - ARM9 CPU, masses of GPIO, a couple of serial lines, USB host *and* slave ports, and a 3.5 colour touchscreen ;-) Gordon MM0YEQ ___ 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: PIC rotator control
On Fri, 2009-10-23 at 08:24 +1000, Andrew Rich wrote: I have used MPLAB and an imitation picstatrt programmer I use OLIMEX development boards and my role out is very quick I decided to use assembly because it made me think and understand how a PIC works Assembler is the right choice here. PICs are pretty interesting in that they are the only CPU that I've found that's considerably *harder* to write code for in C than assembler. Gordon MM0YEQ ___ 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: Portable satellite terminals for disaster relief
JoAnne Maenpaa, K9JKM, wrote: I guess you're observing that AMSAT's GEO proposal has to fit into the GEO satellite commodity market. Should Amsat be working with NetHope to design a better terminal? How do we work with these guys to convince them that they should be using a ham satellite instead of a commercial service? One big advantage of the commercial service is that it exists now. How do we get the money from funding agencies, either government, corporate, or non-profit? Where does Amsat fit in to this world? Have they even heard of us, our history and our capabilities? I've maintained that a GEO satellite is best suited to link widely deployed sectors of the Incident Command System. I think most government-based emergency authorities are not going to be interested in building or funding a system that they do not design and control. They consider amateur radio to be a last-ditch thing that they would rather not count on, they would rather have an in-house system that fits in to their chain of command and shows their funding authorities that they are fully on top of emergency communications and don't need to rely on amateur volunteers coming forward in time of need. A non-governmental organization like NetHope might be more receptive to our proposals. We need to think hard and come up with new ideas. Dan Schultz N8FGV ___ 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: PIC rotator control
Sounds nice. One thing I have to keep an eye on is power being drawn from the USB if I am to use any sort of relays - Original Message - From: Gordon JC Pearce gordon...@gjcp.net To: amsat-bb@amsat.org Sent: Wednesday, October 28, 2009 5:45 PM Subject: [amsat-bb] Re: PIC rotator control On Wed, 2009-10-14 at 07:20 +1000, Andrew Rich wrote: Thanks Yes a small 10 inch laptop could do the work, predict would be used and frequent kep updates I'm looking at using a mini2440 board for just such a thing - ARM9 CPU, masses of GPIO, a couple of serial lines, USB host *and* slave ports, and a 3.5 colour touchscreen ;-) Gordon MM0YEQ ___ 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 No virus found in this incoming message. Checked by AVG - www.avg.com Version: 8.5.423 / Virus Database: 270.14.34/2463 - Release Date: 10/27/09 15:50:00 ___ 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: PIC rotator control
Hi Guys, anybody looked at http://www.mikroe.com/ for building your controlled prototype. I use this board for many project excellent kit and also excellent support. 73 J-F VA2SS 2009/10/28 Gordon JC Pearce gordon...@gjcp.net On Wed, 2009-10-14 at 07:20 +1000, Andrew Rich wrote: Thanks Yes a small 10 inch laptop could do the work, predict would be used and frequent kep updates I'm looking at using a mini2440 board for just such a thing - ARM9 CPU, masses of GPIO, a couple of serial lines, USB host *and* slave ports, and a 3.5 colour touchscreen ;-) Gordon MM0YEQ ___ 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 -- Jean-François Ménard VA2SS =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= AMSAT www.amsat.org / Member #37102 ARRL www.arrl.org =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= ___ 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: PIC rotator control
Very expensive and complete overkill - Original Message - From: Jean-François Ménard jf.va...@gmail.com To: Gordon JC Pearce gordon...@gjcp.net Cc: amsat-bb@amsat.org Sent: Wednesday, October 28, 2009 9:51 PM Subject: [amsat-bb] Re: PIC rotator control Hi Guys, anybody looked at http://www.mikroe.com/ for building your controlled prototype. I use this board for many project excellent kit and also excellent support. 73 J-F VA2SS 2009/10/28 Gordon JC Pearce gordon...@gjcp.net On Wed, 2009-10-14 at 07:20 +1000, Andrew Rich wrote: Thanks Yes a small 10 inch laptop could do the work, predict would be used and frequent kep updates I'm looking at using a mini2440 board for just such a thing - ARM9 CPU, masses of GPIO, a couple of serial lines, USB host *and* slave ports, and a 3.5 colour touchscreen ;-) Gordon MM0YEQ ___ 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 -- Jean-François Ménard VA2SS =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= AMSAT www.amsat.org / Member #37102 ARRL www.arrl.org =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= ___ 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 No virus found in this incoming message. Checked by AVG - www.avg.com Version: 8.5.423 / Virus Database: 270.14.34/2463 - Release Date: 10/27/09 15:50:00 ___ 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: PIC rotator control
It is a prototype board for many project... An exellent learning tool !! 2009/10/28, Andrew Rich vk4...@tech-software.net: Very expensive and complete overkill - Original Message - From: Jean-François Ménard jf.va...@gmail.com To: Gordon JC Pearce gordon...@gjcp.net Cc: amsat-bb@amsat.org Sent: Wednesday, October 28, 2009 9:51 PM Subject: [amsat-bb] Re: PIC rotator control Hi Guys, anybody looked at http://www.mikroe.com/ for building your controlled prototype. I use this board for many project excellent kit and also excellent support. 73 J-F VA2SS 2009/10/28 Gordon JC Pearce gordon...@gjcp.net On Wed, 2009-10-14 at 07:20 +1000, Andrew Rich wrote: Thanks Yes a small 10 inch laptop could do the work, predict would be used and frequent kep updates I'm looking at using a mini2440 board for just such a thing - ARM9 CPU, masses of GPIO, a couple of serial lines, USB host *and* slave ports, and a 3.5 colour touchscreen ;-) Gordon MM0YEQ ___ 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 -- Jean-François Ménard VA2SS =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= AMSAT www.amsat.org / Member #37102 ARRL www.arrl.org =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= ___ 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 No virus found in this incoming message. Checked by AVG - www.avg.com Version: 8.5.423 / Virus Database: 270.14.34/2463 - Release Date: 10/27/09 15:50:00 -- Envoyé avec mon mobile Jean-François Ménard VA2SS =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= AMSAT www.amsat.org / Member #37102 ARRL www.arrl.org =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= ___ 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: Nova Satellite Prediction Program
I would add my vote for that. NOVA is a great program, and with slightly fancier graphics. However, SatPC32 just works, and works well. It easily handles even Mode-S. The learning curve is very moderate, the documentation is superb, and the support is even better. Honesty requires me to comment that the registration fee goes directly to AMSAT for support, and that is another real plus. Alan WA4SCA -Original Message- From: amsat-bb-boun...@amsat.org [mailto:amsat-bb-boun...@amsat.org] On Behalf Of Joel Black Sent: 27 October, 2009 17:14 To: amsat-bb@amsat.org Subject: [amsat-bb] Re: Nova Satellite Prediction Program SatPC32 IMHO... 73, Joel, W4JBB jimcknw...@aol.com wrote: Installed, reinstalled, changed versions- multiple problems with calculating scripts. What program should I change to? ___ 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 ___ 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 Which rotator control to use.
Hi Eric. I have been using Fodtrack along with F6DQM's (Gabriel Rivat) excellent programme Sat_Explorer for over a year now, with no trouble whatsoever, Fodtrack was home built a long time ago in the days of KO-23, UO22 etc and has never given any trouble. Gabriels programme SAT_Explorer can be downloaded free of charge from his excellent web site http.//www.f6dqm.fr, it is very easy to set up and runs perfectly. Best of luck. 73 Howard G0VBT Amsat 6058 Send instant messages to your online friends http://uk.messenger.yahoo.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
[amsat-bb] Re: requesting help on a RF link solution (imaginary ka-bandlink!)
Hi Bob, W7LRD I need to answere your question as well via AMSAT-BB because my emails sent to w7...@comcast.net are alwais rejected to me by your provider. From the point of view of Amateur Radio the best I can suggest to you is the book The Satellite Experimenters Handbook by Martin Davidoff K2UBC 2nd Edition ARRL Order No 3185 ISBN 0-87259-318-5 and also the ARRL UHF MICROWAVE Experimenters's Manual ARRL Order No 3126 ISBN 0-87259-312-6 Those books are full of easy calculations and you can follow it using a small scientific hand held calculator but very important every chapter of the UHF MICROWAVE Experimenter's Manual is full of References and Bibliography that you can find and read/study to go deeply into details on the above matter covering circuits and antennas which are described here in hardware but also with related easy to follow calculations. At the beginning you must go slowly with the above two books but after a few months you will improve and the above matter will come very familiar to you provided that you implement your knoledge following the recommended References and Bibliography. In AMSAT-BB I follow your experimental activity particularly into the S band.congrats ! Best 73 de i8CVS Domenico - Original Message - From: Bob- W7LRD To: i8cvs Sent: Wednesday, October 28, 2009 3:23 AM Subject: Re: [amsat-bb] Re: requesting help on a RF link solution (imaginary ka-bandlink!) Hello Domenico I enjoy your posts, even though many are out of my pay grade. Would you aim me towards a good tutorial place you may know of where I could learn some of the basics. I would like to gain a better understanding of this concept. Thanks 73 Bob W7LRD - Original Message - From: i8cvs domenico.i8...@tin.it To: Samudra Haque samudra.ha...@gmail.com, Amsat-bb amsat-bb@amsat.org Sent: Tuesday, October 27, 2009 5:44:14 PM GMT -08:00 US/Canada Pacific Subject: [amsat-bb] Re: requesting help on a RF link solution (imaginary ka-bandlink!) - Original Message - From: Samudra Haque samudra.ha...@gmail.com To: Amsat-bb amsat-bb@amsat.org Sent: Tuesday, October 27, 2009 11:03 AM Subject: [amsat-bb] requesting help on a RF link solution (imaginary ka-bandlink!) Hi, amsat-bb CQ any satellite link budget expert ! I'm trying to do a calculation on my own based upon published specs for the NASA MRO Ka-band experiment, but am getting some unexpected results for a Ka-band simplex link with Temp=3000K (hypothetical), operating with a Signal to Noise ratio (unitless) figure of 1.171 (representing 4.5 dB eb/no with a data rate of 1 Gbps and a bandwidth of 2.4x10^9 Hz) Question : is 1 gbps not 1x10^9 bps ? Question : if both antennas are 3m parabolic (both are the same type) with 56.4 dBi boresight gain, what would you think the furthest distance the link can perform with SNR of 1.171. I have actually used a padding of 3 dB Eb/No in my link budget, so am not worried about any further signal loss at first (ok, I should be ..) For the exercise, I am choosing a 10 Watt estimated output on an arbitrary basis. So: P_t = 10W G_t = 56.4 dBi = G_r , can we assume the same gain for TX and RX on a parabolic dish ? T = 3000K at receiver SNR = 1.171 required f=32.2 GHz B = 2.4E9 Hz, (bpsk, ldpc code 0.5) DR = 1E9 bps So, I am puzzled why this link budget says the range with these parameters is equal to 4.644 x 10^9 Km -- that seems to be a long distance ! What am I not able to conceptualize. BTW, I know if I send this out, the answer will come to me soon thereafter, but for education, I would like to know where the problem in my understanding lies ! Samudra N3RDX Hi Samudra, N3RDX If I well understand your question is to know what is the maximum free space distance at which you can get a S/N ratio of 4.5 dB using two identical transmitting and receiving systems having the following characteristics: 1) Antenna gain for TX and RX = 56.4 dBi at 32.2 GHz 2) Frequency = 32.2 GHz 3) Overall receiving system noise temperature: T = 3000 kelvin 4) Bandwidth of receiving system = 2.4 x 10^9 Hz 5) TX power 10 W 6) Required Signal to Noise ratio S/N at the unknown distance = 4.5 dB With the above data we first calculate the receiver noise floor Pn = KTB where: K = Boltzmann constant = 1.38 x 10^ -23 (Joule/kelvin) T = Overall System Noise Temperature = 3000 kelvin B = Bandwidth of receiving system = 2.4 x 10^9 Hz Working out the numbers we get the following RX noise floor Pn = (1.38 x 10^ -23) x (3000) x (2.4 x 10^9) = 1 x 10^-10 watt and 10 x [ log (1 x 10^-10)] = - 100 dBW or - 70 dBm 10 Link budged calculation TX power = 10 W =..+ 40
[amsat-bb] Cute competition winners
Cute Re-entry Competition Winners Declared It seems that when a satellites, reache an altitude as low as about 170km they will be down very quickly. According to Space Track elements, and InstanTrak tracking software Cute was still orbiting when the perigee was below 150 Km. My theory is that cubesats stay in orbit longer because they have a large mass relative to their very small cross section and so experience far drag than bulkier objects. Using that idea I ran the last element set for several orbits and made an arbitrary decision that re-entry probably took place at a perigee of 130Km or so thus putting re-entry pretty much dead centre between two competition entries. I therefore declare Ib OZ1MY and David G0MRF as joint winners !!! On receipt of current postal addresses I will mail out a patch kit to each of the lucky winners. Thanks to Ib, David and everyone else who took part, it was fun to plot the curves and I learned a bit about atmospheric density and solar flux. 73 John G7HIA PS IPS Radio and Space Services, have a useful paper on satellite orbital decay calculations. Thanks to Ken GW1FKY for sending me a copy. ___ 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] using a microsat as a potential high altitude VHF reflector
Hi all, I read with interest an article on the web ECHO - America's First Communications Satellite By John R. Pierce which is available here: http://www.smecc.org/john_pierce___echoredo.htm I know ham radio operators love using their hand helds to communicate using active transponders or active repeaters in space... no issue with that. were there any ham radio projects (either through amsat-na or abroad) that implemented a passive reflector on an orbital vehicle like Project Echo I quote from http://www.satmagazine.com/cgi-bin/display_article.cgi?number=490218137 The Echo-1 Balloon Satellite as it sits, fully inflated, at a Navy hangar in Weeksville, North Carolina. The spacecraft measured 100 feet across when deployed, and was nicknamed a ‘satelloon’ by those involved in the project. The mylar film balloon acted as a passive communications reflector for transcontinental and intercontinental telephone (voice), radio and television signals. Echo 1 re-entered the atmosphere May 24, 1968. What strikes me is the implications of a large large very large antenna (reflector), if only it could be reflective on one side of the sphere only (any ideas?) The Echo 2 was a 135-foot rigidized inflatable balloon satellite. The satellite is shown undergoing tensile stress test in a dirigible hanger at Weekesville. The satellite, 50 times more rigidized than Echo I. When folded, the satellite is packed into the 41-inch diameter canister shown in the foreground. Did early amsat folks consider duplicating / adding to any of these projects or launch their own 'satelloon' that did not carry an active RF payload ? Could we outfit one of our future microsats to provide a reflector to aid in Earth-LEO DXing like meteor-scatter ? 73 de Samudra, N3RDX ___ 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: using a microsat as a potential high altitude VHF reflector
There are two neat concepts from the early days of communications experiments using satellites and Echo is one of them (the other is SCORE). There were a lot of ideas for follow on echos...one used a gravity gradient pole to stop the balloon from spinning and keeping it pointed to the earth, allowing a directional reflector to be installed in the balloon...another used a radar reflector like concept inside the balloon to increase the amount of DB that returned... The problems were large however. Doppler shift and tracking were issues at the time (and probably still are)..the antennas were going to have to be large (really large). My elmer in Dallas when he was in the USAF did some radar experiments with echo...I got to see it a few times. SCORE probably has more relevance to todays possibilities. Robert WB5MZO _ New Windows 7: Find the right PC for you. Learn more. http://www.microsoft.com/windows/pc-scout/default.aspx?CBID=wlocid=PID24727::T:WLMTAGL:ON:WL:en-US:WWL_WIN_pcscout:102009 ___ 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] Sat status update
Hello I have tidied things up a bit and added a graph for ISS Please let me know if you would like to see a satellite added http://vk4tec.no-ip.org/sat_status/ Andrew VK4TEC ___ 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: using a microsat as a potential high altitude VHFreflector
One drawback of the design was the high drag from such a large structure, coupled with the low mass. The end result was a satellite with a low ballistic coefficient and hence a short lifetime. John WA4WDL -- From: Samudra Haque samudra.ha...@gmail.com Sent: Wednesday, October 28, 2009 3:46 PM To: Amsat-bb amsat-bb@amsat.org Subject: [amsat-bb] using a microsat as a potential high altitude VHFreflector Hi all, I read with interest an article on the web ECHO - America's First Communications Satellite By John R. Pierce which is available here: http://www.smecc.org/john_pierce___echoredo.htm I know ham radio operators love using their hand helds to communicate using active transponders or active repeaters in space... no issue with that. were there any ham radio projects (either through amsat-na or abroad) that implemented a passive reflector on an orbital vehicle like Project Echo I quote from http://www.satmagazine.com/cgi-bin/display_article.cgi?number=490218137 The Echo-1 Balloon Satellite as it sits, fully inflated, at a Navy hangar in Weeksville, North Carolina. The spacecraft measured 100 feet across when deployed, and was nicknamed a ‘satelloon’ by those involved in the project. The mylar film balloon acted as a passive communications reflector for transcontinental and intercontinental telephone (voice), radio and television signals. Echo 1 re-entered the atmosphere May 24, 1968. What strikes me is the implications of a large large very large antenna (reflector), if only it could be reflective on one side of the sphere only (any ideas?) The Echo 2 was a 135-foot rigidized inflatable balloon satellite. The satellite is shown undergoing tensile stress test in a dirigible hanger at Weekesville. The satellite, 50 times more rigidized than Echo I. When folded, the satellite is packed into the 41-inch diameter canister shown in the foreground. Did early amsat folks consider duplicating / adding to any of these projects or launch their own 'satelloon' that did not carry an active RF payload ? Could we outfit one of our future microsats to provide a reflector to aid in Earth-LEO DXing like meteor-scatter ? 73 de Samudra, N3RDX ___ 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] Re: using a microsat as a potential high altitude VHF reflector
were there any ham radio projects (either through amsat-na or abroad) that implemented a passive reflector on an orbital vehicle like Project Echo Not long ago I saw some webpages and emails about some hams using ISS (or was it Mir?) as a passive reflector. Coincidently, I was reading about the West Ford project, which was launches of millions of small wire dipoles to be used as reflectors. Some of those clusters are still in orbit. I wonder if they are still in a dense enough field to reflect the 8 Ghz? signal they were designed for. 73, Drew KO4MA ___ 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: using a microsat as a potential high altitude VHF reflector
Drew. I had forgotten about West Ford...but they are all gone. While in grad school we tried some reflection test using the then prototype of the SPS 48E and there was nothing... Robert WB5MZO Date: Wed, 28 Oct 2009 16:12:54 -0400 From: glasbren...@mindspring.com To: samudra.ha...@gmail.com CC: amsat-bb@amsat.org Subject: [amsat-bb] Re: using a microsat as a potential high altitude VHF reflector were there any ham radio projects (either through amsat-na or abroad) that implemented a passive reflector on an orbital vehicle like Project Echo Not long ago I saw some webpages and emails about some hams using ISS (or was it Mir?) as a passive reflector. Coincidently, I was reading about the West Ford project, which was launches of millions of small wire dipoles to be used as reflectors. Some of those clusters are still in orbit. I wonder if they are still in a dense enough field to reflect the 8 Ghz? signal they were designed for. 73, Drew KO4MA ___ 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 _ Windows 7: Simplify your PC. Learn more. http://www.microsoft.com/Windows/windows-7/default.aspx?ocid=PID24727::T:WLMTAGL:ON:WL:en-US:WWL_WIN_evergreen1:102009 ___ 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: using a microsat as a potential high altitude VHF reflector
Space-Track is still tracking several clusters of Westford needles, although they are certainly spread out and thinning fast. Some are still nearly in their original orbits. As evidence: WESTFORD NEEDLES 1 00602U 63014E 09300.68434638 +.0003 +0-0 +1-3 0 07665 2 00602 087.3316 050.1496 0032690 004.4295 355.6847 08.67203352471339 73, Drew KO4MA ___ 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] Survey: Top 250 grids
Hi all! After recently working a number of rare grids activated by our fellow satellite ops, (again THANK YOU!!) I've been looking over the grid map and wondered what grids are most needed. I, like most, have grids that others may dream of working and confirming and vice versa. Then, there are those grids that are so common, most everybody has worked and confirmed them. Since there are no HEO's and only the FM birds with a couple of linear birds, this survey will be focused on the North American area. I am undertaking a task to get a better reading on what grids are outstanding in need of activation. I am looking at obtaining the top 25 grids from the predominately 10 grid fields covering the U.S., Canada and Mexico, for the total of 250 grids. Yes, most of these grids will be in the U.S., however, I'm sure there will be some mention of VE and XE grids as well. What I would like everybody to do is take some time and look at your grid map and write down 25 grids from each of the grid fields that cover the U.S., Canada and Mexico. Those grid fields are: CN, DN, EN, FN, CM, DM, EM, FM, DL, EL. If you don't need at least 25 grids from a particular grid field, no problem, just enter those you still need. Example. Let's say you only need three grids from DM, they are DM74, 75, 76. Just enter those three. To make things simple and easy I will give an example of how the data can be entered and e-mailed to me. Here is an example. CN 79, 82, 93, 95, 99 DN 02, 03, 07, 13, 15, 17, 19, 22, 24, 25, 34, 37, 38 As you can see, it's relatively easy, and very easy if you've kept up on your grid map. :) A couple of notices. 1. Please, do not send any water grids since any operation from them is sporadic and most cases, impracticle to activate for most of us. 2. Please send your data to me via e-mail, attaching it to this e-mail will be fine. The cutoff date is November 14, 2009. This will give all plenty of time to look over their maps and data. Questions, comments or just sending the data, please send an e-mail. Looking forward to receiving your replies! 73, Jeff WB3JFS Las Vegas, NV DM26 ___ 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: FS item (Arrow)
The PCR-1000 and the UT-10 L-band module have been sold. The Arrow antenna is still available! Keep in mind the current new/retail price for this antenna is $139 (plus shipping). That makes this one better than new ;-) 1) Arrow II Antenna 146/437-10WBP Satellite version with built-in diplexer and split boom. Condition: nearly new, only assembled about 5 times. Elements/boom neatly numbered via label-maker tape. $100 + shipping/insurance. 73, Mark N8MH Date: Mon, 26 Oct 2009 15:51:50 -0400 Delivered-To: marklhamm...@gmail.com Subject: FS items (Arrow, PCR-1000, 1.2 GHz module for TS-790). From: Mark L. Hammond marklhamm...@gmail.com To: amsat-bb@amsat.org Hello AMSAT-BB, I need to pursue a tower/rotor/antenna project. Therefore, I am selling some items in the shack to help fund the project. The prices are fair and therefore firm. I'm giving the BB a shot before I take these to a local hamfest or eBay. Prices do not include shipping/insurance. SOLD 2) Icom PCR-1000 receiver. Includes receiver, serial cable, and power supply. Condition: few minor scuffs/scratches, perfect working condition. (The variable bandwidth permits reception of 38k4 packet signals!) $250 + shipping/insurance. SOLD 3) UT-10 1.2 GHz L-band module for Kenwood TS-790. This is a plug-n-play module, about a 5-10 min. no-tuning install. Includes screws. Condition: Perfect working order, low transmit time, full 10W output. Price: $475 + shipping/insurance. Please contact me directly offlist at: marklhammond AT gmail DOT com Mark L. Hammond [N8MH] ___ 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: using a microsat as a potential high altitude VHFreflector
- Original Message - From: Samudra Haque samudra.ha...@gmail.com To: Amsat-bb amsat-bb@amsat.org Sent: Wednesday, October 28, 2009 8:46 PM Subject: [amsat-bb] using a microsat as a potential high altitude VHFreflector Hi all, I read with interest an article on the web ECHO - America's First Communications Satellite By John R. Pierce which is available here: http://www.smecc.org/john_pierce___echoredo.htm I know ham radio operators love using their hand helds to communicate using active transponders or active repeaters in space... no issue with that. were there any ham radio projects (either through amsat-na or abroad) that implemented a passive reflector on an orbital vehicle like Project Echo I quote from http://www.satmagazine.com/cgi-bin/display_article.cgi?number=490218137 The Echo-1 Balloon Satellite as it sits, fully inflated, at a Navy hangar in Weeksville, North Carolina. The spacecraft measured 100 feet across when deployed, and was nicknamed a ‘satelloon’ by those involved in the project. The mylar film balloon acted as a passive communications reflector for transcontinental and intercontinental telephone (voice), radio and television signals. Echo 1 re-entered the atmosphere May 24, 1968. What strikes me is the implications of a large large very large antenna (reflector), if only it could be reflective on one side of the sphere only (any ideas?) The Echo 2 was a 135-foot rigidized inflatable balloon satellite. The satellite is shown undergoing tensile stress test in a dirigible hanger at Weekesville. The satellite, 50 times more rigidized than Echo I. When folded, the satellite is packed into the 41-inch diameter canister shown in the foreground. Did early amsat folks consider duplicating / adding to any of these projects or launch their own 'satelloon' that did not carry an active RF payload ? Could we outfit one of our future microsats to provide a reflector to aid in Earth-LEO DXing like meteor-scatter ? 73 de Samudra, N3RDX Hi Samudra, N3RDX Early 13 august 1960 about 50 years ago I have received the ECHO 1A 45 mW beacons transmitting at 108.00 and 108.03 MHz and also I got an excellent visual of the big satellite balloon only looking at it in the sky with naked eye Receiving radio signals and looking at the orbiting satellite at the same time it was a very exciting experience and I newer forget ! I was using a home brewed downconverter for 108 MHz with two low noise triodes 6AN4 in a front end grounded grid circuit. The second IF receiver tuned at 27.963 MHz was an Hallicrafters SX-28 and the antenna was a qubical quad. By the way the NASA and GSFC ground stations where transmitting to the reflecting surface of the above passive satellite a very very high EIRP at 960 MHz and 2390 MHz using big dishes. The experience gained with the passive ECHO satellites demonstrates that they are not convenient at all so that the project was soon abandoned. 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
[amsat-bb] Centerfire Yagi antennas
Anyone had any experience with these? http://www.centerfireantenna.com/vhf2myagi.html They look to be a good buy and I was thinking of maybe getting one for LEO use. 73, Michael, W4HIJ ___ 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: Centerfire Yagi antennas
They only bad review at eHam panned them for being a bit lightweight in construction. http://www.eham.net/reviews/detail/8191 Jim KQ6EA --- On Wed, 10/28/09, Michael Tondee mat...@netcommander.com wrote: From: Michael Tondee mat...@netcommander.com Subject: [amsat-bb] Centerfire Yagi antennas To: Amsat BB amsat-bb@amsat.org Date: Wednesday, October 28, 2009, 4:51 PM Anyone had any experience with these? http://www.centerfireantenna.com/vhf2myagi.html They look to be a good buy and I was thinking of maybe getting one for LEO use. 73, Michael, W4HIJ ___ 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] Re: using a microsat as a potential high altitude VHFreflector
Domenico, I had no idea absolutely that you would have responded with such relevant experience !!! It is an amazing story to hear. The recent interest and work on inflatable antennas may be the most interesting chapter yet (ref: JPL DESCANSO publications) in antenna theory. Thanks -samudra Hi Samudra, N3RDX Early 13 august 1960 about 50 years ago I have received the ECHO 1A 45 mW beacons transmitting at 108.00 and 108.03 MHz and also I got an excellent visual of the big satellite balloon only looking at it in the sky with naked eye Receiving radio signals and looking at the orbiting satellite at the same time it was a very exciting experience and I newer forget ! I was using a home brewed downconverter for 108 MHz with two low noise triodes 6AN4 in a front end grounded grid circuit. The second IF receiver tuned at 27.963 MHz was an Hallicrafters SX-28 and the antenna was a qubical quad. By the way the NASA and GSFC ground stations where transmitting to the reflecting surface of the above passive satellite a very very high EIRP at 960 MHz and 2390 MHz using big dishes. The experience gained with the passive ECHO satellites demonstrates that they are not convenient at all so that the project was soon abandoned. 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
[amsat-bb] Re: Hopefully - Some ITAR Clarifications.
Agreed, but you have to remember to GO THERE. E-mail comes to me and my e-mail client rejects most of the spam and sorts the good stuff into folders. Much easier Samudra Haque wrote: With a forum, you can unclutter your mailbox, and also the forum system can always tag messages according to a timeline/subject/thread whatsoever, so if you are really busy (are we not all busy ... its a hobby of course) then just wait to log on, and then when you do, the system can show you (if desired) all of the unread messages in the various topics you are subscribed to (Think: USENET Newsgroup style focus) unless you wish to say catchup and then all is marked as read. In your current system of receiving messages from the amsat-bb mailing list, unless you have a very large mailbox and never delete your message pool, you are (we are..) all keeping separate message copies for each and every reply, instead of just the delta's for each message kept on a server somewhere. This method is not only bandwidth inefficient, it also means YOU the user are responsible for tracking your threads and keeping up to date. Would you not wish to lessen your burden just a little bit by having the system keep track of where you are in your hobby ? If you like, the forum can also mail all relevant postings to you as regular SMTP mail, so if you don't like the forum, that's ok too. -samudra N3RDX On Mon, Oct 26, 2009 at 6:06 PM, Tony Langdon vk3...@gmail.com wrote: At 08:37 AM 10/27/2009, Samudra Haque wrote: Yes, I usually take care to divide my correspondence amongst the particular groups I am working with, and this is also the basis in which I recently proposed moving to (a) moderated forum (such as phpBB) or (b) sub-dividing the amsat-bb list into amsat-engineering If AMSAT goes to a forum, I'm out of here, I can't cope with the volume of messages on a forum, much easier in email. Email lists can be moderated too, but the separation might be a good way to simplify ITAR compliance. 73 de VK3JED / VK3IRL http://vkradio.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 No virus found in this incoming message. Checked by AVG - www.avg.com Version: 8.5.423 / Virus Database: 270.14.31/2458 - Release Date: 10/25/09 08:10:00 ___ 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] Stealth Satellite Station?
I currently live in a rental house and an outside antenna is out of the question. I asked about putting up a satellite TV dish at my own expense last year and received and flat out NO. So, my current options are as follows: 1. Going out to my car and working the FM birds with my Icom 2720H and 19 whip. 2. Working the FM birds from the back/front yard or possibly inside the house with my Icom W32A and Elk LP antenna. 3. Setting up my 2720 in the house with some sort of stealth antenna and give a try at satellite APRS. Obviously options 1 and 3 still allow for option 2. Has anyone tried any form of stealth antenna for Satellites. I am really interested in the idea of combining the satellites and aprs together. -- Kent R Frazier, K5KNT AMSAT #36765, ARRL, San Angelo Amateur Radio Club, Tom Green County - ARES Sent from San Angelo, TX, United States ___ 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: Stealth Satellite Station?
Are you able to put up a temporary mast of modest height? I've used a 2 foot section of fence pipe in a bucket of quickcrete as a base and then use a smaller diameter of fence pipe to slide into the piece that is held in the bucket of cement. I've gone as high as 30' with this kind of set-up by putting it next to a pillar, strapping it to the pillar with a truck load strap and then guying it with rope (this is how I put up my 6M summertime set-up...worked great). You certainly don't need to go 30'...12 or 15' might be just fine. If the landlord could see that it's not being bolted to his property and is basically a portable set-up, he might be a lot more open to it. In fact, I wouldn't even ask him. If you're not attaching it to his house and there are no restrictions to an antenna in the back-yard, go for it. -Original Message- From: amsat-bb-boun...@amsat.org [mailto:amsat-bb-boun...@amsat.org] On Behalf Of Kent Frazier Sent: Wednesday, October 28, 2009 6:03 PM To: AMSAT-BB@amsat.org Subject: [amsat-bb] Stealth Satellite Station? I currently live in a rental house and an outside antenna is out of the question. I asked about putting up a satellite TV dish at my own expense last year and received and flat out NO. So, my current options are as follows: 1. Going out to my car and working the FM birds with my Icom 2720H and 19 whip. 2. Working the FM birds from the back/front yard or possibly inside the house with my Icom W32A and Elk LP antenna. 3. Setting up my 2720 in the house with some sort of stealth antenna and give a try at satellite APRS. Obviously options 1 and 3 still allow for option 2. Has anyone tried any form of stealth antenna for Satellites. I am really interested in the idea of combining the satellites and aprs together. -- Kent R Frazier, K5KNT AMSAT #36765, ARRL, San Angelo Amateur Radio Club, Tom Green County - ARES Sent from San Angelo, TX, United States ___ 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
