November 2011 - AMSAT-BB - mailman.amsat.org

simplest USB rotor interface
by Wayne Estes 17 Nov '11

17 Nov '11

As an AMSAT Area Coordinator, I occasionally get questions about rotor interfaces. So I need to become better informed about the interface options. I'm well aware of the LVBtracker, but to me it seems to be overkill for the intended purpose. It's not necessary for a rotor interface to have a big box, display, and control switches. The interface really only needs to contain A/D and D/A converters. All displays and controls can be implemented "virtually" on the computer's screen. Is there a simple and cheap USB interface for the G-5500 rotor? Something small and simple like FODtrack, but with a USB port? I'm aware of WinRotor USB, but nobody in North America seems to use it. Wayne Estes W9AE Oakland, Oregon, USA, CN83ik

7 6

Re: simplest USB rotor interface
by Thomas Doyle 17 Nov '11

17 Nov '11

The saebrtrack from AMSATs own Mark Hammond is probably the best documented DIY board. The processor is a bit expensive and slow but the one I built does work. I had a FoxDelta ST3 for a while but had problems with it right from the start. I was able to return it without any trouble. It is probably the best deal out there. The easiest part of building your own is the software. The program does not do much so it is straightforward and easy to write. An lcd display of some type is invaluable in troubleshooting but you can use a terminal emulation program on a computer for set up. The buttons are not needed if you have a G5500. The case and cables are the most work. http://sites.google.com/site/marklhammond/saebrtrack The LVB Tracker from AMSAT is great in that you can "have it your way". Buy only what you need from a bare board to a completed unit. It is also a nice way to help out AMSAT. http://www.amsat-na.com/store/category.php?c=Hardware Sent from my computer. 73 W9KE tom ...

1 0

Re: Ao-51 at 2100z today
by Clint Bradford 17 Nov '11

17 Nov '11

>> ... how do you all write down callsigns? I am not sure what your problem is. I mean ... -one hand for the Yagi -one hand for the radio -one hand for the speaker-mic -one hand for the clipboard -one hand for the pencil -one hand for the tall glass of iced tea -one hand for your smartphone with its satellite tracking program running (grin) I will sometimes use a smartphone voice recorder app to record passes, for later review. In a shirt pocket, to free up my other six hands. Additionally, I have built a little tray wide enough to accommodate my HT on the boom of my Yagi. Helps free another hand, as well as "counter-balancing" the front-heavy antenna. Photos at ... http://web.me.com/clintbradford/k6lcs/Photos/Photos.html ... and ... http://web.me.com/clintbradford/Work-Sat/My_Gear.html Clint Bradford, K6LCS http://www.work-sat.com

2 1

Fwd: Mystery of the Lunar Ionosphere
by GW1FKY＠aol.com 17 Nov '11

17 Nov '11

Hi, While we are on the subject of the Moon and looking back at missions - take a look at the web pages I have forwarded. Should prove quite a talking point in terms of our hobby - ionosphere and radio communications on and around the Moon. Regards Ken Eaton GW1FKY

3 3

Ao-51 at 2100z today
by ryan woods 17 Nov '11

17 Nov '11

Well this was the first time for me to work any satellites in a really long time just wanted to day AO-51 still sounds great and i hope it stays that way for a long time. Im running a wouxon ht to an arrow on a tripod it works good but not as well at my th-d7a. Anyway just want to get some input while im writing this....... I am always portable when im on the birds and can never really get my logging down so just wanted to know How everyone else goes about it?......... Thanks in advance 73 de KD8ATF Sent from Yahoo! Mail on Android

1 0

FUNcube-1 Forum + ISS Columbus UHF Station
by Trevor . 17 Nov '11

17 Nov '11

See FUNcube-1 Satellite Forums http://www.uk.amsat.org/2011/11/16/funcube-1-satellite-forums/ and UHF Station on ISS Columbus module http://www.uk.amsat.org/2011/11/17/uhf-station-on-iss-columbus-module/ 73 Trevor M5AKA

1 0

AO-10?
by KG0MW-Chad Phillips 17 Nov '11

17 Nov '11

Just wondering if anyone has tried listening for old ao-10. Alway's hoping she will spring back to life... chad kg0mw

2 1

ARISSat-1 (37772) decay
by DeYoung James 16 Nov '11

16 Nov '11

Greetings, First, thank you Mineo for reading the AMSAT Journal and making several of my papers available on your web site. My AMSAT Journal paper published in the March/April 2011 issue is actually still fairly valid for the scenarios shown in the paper. The solar flux has turned out to be somewhat higher than was used/predicted in the paper. This has caused the atmospheric densities to be higher which results in higher decay rates. When I wrote the paper I had this nagging feeling that stopping the release height scenarios at 370-km was not going to be high enough. We are very fortunate that the ISS was boosted to such a height before release of ARISSat-1 and not after release! There is a valuable lesson, I think, to be made with respect to predicting satellite decay dates far into the future. The future state of the atmosphere, i.e. the atmospheric density that the satellite will pass through is poorly predictable in the long-term, say starting greater than a week or two into the future. Predictions of satellite decay dates months in the future should be evaluated with the understanding that your date of prediction errors may be large. The errors are due to the future uncertainties of the orbital path which grow quickly with time in a prediction. The atmospheric density is not the only source of error. Your orbit model, the integrator, and the accounting of the gravitational and drag forces among others will affect your results. Predictions of satellite decay dates are not do-and-forget. The general process is to make a prediction, get new measured observations of the height in the future, and at some point re-do your prediction when the errors become significant to you. With that all said here is my current prediction using the same tools used in the AMSAT J. paper and produced as of 2011 November 13th. The decay of ARISSat-1 (37772) will happen nominally on 2012 January 30th with a 10% rule-of-thumb error allowance of 18 days around this date. The errors may be larger than the rule-of-thumb indicates! Jim, N8OQ

2 1

NASA Twitting Mars Rover Launch
by Clint Bradford 16 Nov '11

16 Nov '11

RELEASE: 11-387 NASA INVITES 150 LUCKY TWITTER FOLLOWERS TO LAUNCH OF MARS ROVER WASHINGTON -- NASA has invited 150 followers of the agency's Twitter account to a two-day launch Tweetup on Nov. 23 and 25 at the agency's Kennedy Space Center in Florida. The Tweetup is expected to culminate in the launch of the Mars Science Laboratory's Curiosity rover aboard an Atlas V rocket from nearby Cape Canaveral Air Force Station. The launch window is scheduled to open at 10:25 a.m. EST on Nov. 25. Curiosity's arrival at Mars is anticipated in August 2012 near Gale Crater. During the nearly two-year prime mission, the rover will investigate whether a selected area of Mars offered environmental conditions favorable for microbial life and preserved that evidence, if it existed. Tweetup participants were selected from more than 1,050 people who registered online. They will share their Tweetup experiences with their followers through the social networking site Twitter. Participants represent the United States, Australia, Belgium, Brazil, Canada, France, Germany, Ireland, Spain and the United Kingdom. Attendees from the U.S. come from the District of Columbia and 37 states: Alabama, Arizona, California, Connecticut, Florida, Georgia, Hawaii, Idaho, Illinois, Indiana, Iowa, Kansas, Kentucky, Louisiana, Maine, Maryland, Massachusetts, Michigan, Minnesota, Mississippi, Missouri, Nebraska, New Hampshire, New Jersey, New Mexico, New York, North Carolina, Ohio, Oregon, Pennsylvania, South Carolina, Tennessee, Texas, Utah, Virginia, Washington and Wisconsin. Beginning at 11 a.m. on Wednesday, Nov. 23, NASA will broadcast a portion of the Tweetup when attendees talk with Jim Green, Planetary Science division director, and Doug McCuistion, Mars Exploration program director, both at NASA Headquarters in Washington. Engineers from NASA's Jet Propulsion Laboratory, Pasadena, Calif., where the rover was designed and built will speak, as will mission scientists. To watch the broadcast, visit: http://www.ustream.tv/channel/nasa-tweetup Participants also will tour Kennedy and Cape Canaveral, including a close-up visit to the launch pad. On launch day, they will speak with NASA Administrator Charles Bolden; Leland Melvin, NASA's assistant administrator for education; astronaut Doug Wheelock and Bill Nye the Science Guy. Reporters credentialed to cover the launch also may cover the NASA Tweetup at Kennedy's press site. Reporters interested in interviewing Tweetup attendees in advance should contact Stephanie Schierholz at 202-358-1100 or stephanie.schierholz(a)nasa.gov. NASA has invited its Twitter followers to attend eight previous launches: NASA's newest Earth-observing satellite, NPP; the twin GRAIL spacecraft bound for the moon; the Juno spacecraft on its way to Jupiter; and five space shuttle missions. To follow participants on Twitter as they experience the prelaunch events and Curiosity's liftoff, follow the #NASATweetup hashtag and the list of attendees at: https://twitter.com/NASATweetup/mars-curiosity JPL manages the mission. NASA's Launch Services Program at Kennedy is managing the launch. For more information about the Mars Curiosity rover, visit: http://www.nasa.gov/msl Interact with the mission via Twitter and Facebook accounts at: http://Twitter.com/MarsCuriosity http://Facebook.com/MarsCuriosity To connect with NASA on Twitter and other social networking sites, visit: http://www.nasa.gov/connect -end- Clint Bradford clintbradford(a)mac.com

1 0

5 in EM55
by wa4hfn＠comcast.net 16 Nov '11

16 Nov '11

Congrats to Tom KA6SIP for award #42 5 in em55 WA4HFN Damon For info about this award look me up on qrz.com

1 0