OT - but of interest?
As many on this list are amateur radio operators the following might be of interest:
The project asks amateurs to monitor transmissions from cell phones that have
been placed in orbit.
From the homepage:
"PhoneSat satellites are emitting packets on the amateur radio spectrum to
report different types of message. The details of these packets can be found on
the packets page. If you are an amateur radio operator and you can receive these
packets, you have the great opportunity to contribute to the project by
submitting them. The dashboard page will give you all the information you need
to track the satellites in real time."
--
Bob Smither, PhD Circuit Concepts, Inc.
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Top 10 reasons why those that love the United States should not support
the Republican or Democratic party:
First Amendment; Second Amendment; Third Amendment; Fourth Amendment;
Fith Amendment; Sixth Amendment; Seventh Amendment; Eighth Amendment;
Ninth Amendment; Tenth Amendment
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Smither@C-C-I.Com http://www.C-C-I.Com 281-331-2744(office) -4616(fax)
On 04/26/2013 06:01 AM, Bob Smither wrote:
As many on this list are amateur radio operators the following might be of interest:
http://www.phonesat.org/
The project asks amateurs to monitor transmissions from cell phones that have
been placed in orbit.
From the homepage:
"PhoneSat satellites are emitting packets on the amateur radio spectrum to
report different types of message. The details of these packets can be found on
the packets page. If you are an amateur radio operator and you can receive these
packets, you have the great opportunity to contribute to the project by
submitting them. The dashboard page will give you all the information you need
to track the satellites in real time."
Will radiation fry the cell phones before thy burn up on re-entry?
They are expected to re-enter within weeks so there is a good
chance they will not see a radiation event before they burn up.
--
Chuck Forsberg WA7KGX caf@omen.com www.omen.com
Developer of Industrial ZMODEM(Tm) for Embedded Applications
Omen Technology Inc "The High Reliability Software"
10255 NW Old Cornelius Pass Portland OR 97231 503-614-0430
On 4/26/13 6:01 AM, Bob Smither wrote:
As many on this list are amateur radio operators the following might be of interest:
http://www.phonesat.org/
The project asks amateurs to monitor transmissions from cell phones that have
been placed in orbit.
Except that the transmissions are from a separate radio. The cellphones
are being used only for their sensors.
On 4/26/13 9:18 AM, Chuck Forsberg WA7KGX N2469R wrote:
On 04/26/2013 06:01 AM, Bob Smither wrote:
As many on this list are amateur radio operators the following might
be of interest:
to track the satellites in real time."
Will radiation fry the cell phones before thy burn up on re-entry?
They are expected to re-enter within weeks so there is a good
chance they will not see a radiation event before they burn up.
Total dose will be very small (after all astronauts live in LEO)
So you'd worry about cosmic rays and single event effects.
A lot of modern parts are pretty latchup immune for a variety of reasons.
Things that tend to die are FETs that are switching power.. they don't
have much voltage margin on the gates and dumping a bunch of charge from
a single event might push it over the threshold and you get a gate
rupture (SEGR).
SEU and related SEFI are probably pretty unlikely. Feature size is
small, and the odds of hitting one that's actually being used are low.
There's an external watchdog to reset it as well. The camera will
probably show some speckles.
They fly a lot of unmodified commercial equipment on ISS (and on
Shuttle, when we still flew it) and they typically have MTBF of a month
or so for the really soft parts. Most stuff will last a year before it
dies.
It's unclear whether there has ever been a documented case of a
satellite failing due to latchup in space. Surrey is pretty cagey about
their on-orbit performance at that level of detail, but they use mostly
commercial parts.