> It should have been simple, but one *major* component of both SuitSat and ARRISat was the triple redundant timer that kept the transmitters off for 15 minutes after 3 toggle switches were turned on. This allowed the
> satellites sufficient time to travel away from the ISS before the low-power transmitting began. Noteworthy to say that this system has failed with the ARRISat launch, and nobody seemed to care or even notice. Not that the timer has failed - I am sure it did not transmit within 15 minutes after being turned on. The problem was that one of the astronauts flicked the switches as soon as he and the satellite was outside the station (instead of switching them on just before they let go), but then a lengthy delay occurred as they discovered the missing UHF antenna. Meanwhile the timer expired and ARRISat began operating & transmitting. Clear evidence of this are sstv images received from ground-stations which show the astronaut holding the satellite in his hands : http://wordpress.projectoscar.co.uk/?page_id=543 and others. Andreas - VK4HHH ________________________________ From: Stephen E. Belter <s...@wintek.com> To: "amsat-bb@amsat.org" <amsat-bb@amsat.org> Sent: Thursday, 19 January 2012 3:07 AM Subject: [amsat-bb] Re: Probably a silly idea... Raydel: Unfortunately, nothing concerning the ISS is easy. The ISS has had problems with radio frequency interference (RFI) in the past, and an RFI problem could affect the docking of supply vessels (e.g., a collision) or spacewalking astronauts. Astronaut safety is paramount. As a result, all non-critical radios (including ham radios) are turned off during docking, repositioning of the Soyuz escape capsules, and space walks. So a hitchhiking amateur satellite would need to be *reliably* remote controllable from inside the ISS and maybe from the ground too. It should have been simple, but one *major* component of both SuitSat and ARRISat was the triple redundant timer that kept the transmitters off for 15 minutes after 3 toggle switches were turned on. This allowed the satellites sufficient time to travel away from the ISS before the low-power transmitting began. Catching a ride on an unmanned rocket is difficult and expensive. Getting to the ISS and on any manned mission is near impossible. It is a real credit to the dedicated volunteers of AMSAT that we've ever been on board the shuttle or ISS. 73, Steve N9IP -- -----Original Message----- From: amsat-bb-boun...@amsat.org [mailto:amsat-bb-boun...@amsat.org] On Behalf Of Andre Sent: Wednesday, January 18, 2012 11:42 AM To: amsat-bb@amsat.org Subject: [amsat-bb] Re: Probably a silly idea... Op 18-1-2012 17:06, Raidel Abreu Espinet schreef: > Hi all, > > This is probably a silly idea but who knows.... > > ARRISat-1 was a wonderfull satellite but with a short life. The ISS instead > is a wonderfull platform, of course I know how difficult is to install inside > it new radios and antennas for cross-repeaters, but how difficult is really > to take a small box and firmly attach it to some low risk part of the ISS, > the satellite-box will use its own power solar cells and antennas and the ISS > is just the carrier. > > It may be something silly but probably not difficult, if the astronauts made > a "hand launch" with ARISSat-1/KEDR why can not them just hold it with > latches in a low risk part of the ISS. Of course if a battery is a risk we > can just design a simple system capable of work only in sun light. > > If you think this is a bad idea, just ignore it, if not, well who knows, may > be some day an astronaut attach an small satellite in the ISS side.... > > 73, > Raydel, > CM2ESP > Este mensaje ha sido enviado mediante el servicio de correo electronico que > ofrece la Federacion de Radioaficionados de Cuba a sus miembros para > respaldar el cumplimiento de los objetivos de la organizacion y su politica > informativa. La persona que envia este correo asume el compromiso de usar el > servicio a tales fines y cumplir con las regulaciones establecidas. > _______________________________________________ > 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 > Not a bad idea, in fact it has been done before and at one time was planned a seccond time, lookup pcsat 2 and pcsat 3. Not sure why pcsat 3 never flew, from what I understood it was ready to go awaiting rfi aprovement. 73 Andre PE1RDW _______________________________________________ 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
