| |
CX2SA > SATDIG 22.09.13 21:03l 636 Lines 23394 Bytes #999 (0) @ WW
BID : AMSATBB8324
Read: GUEST IV3JER
Subj: AMSAT-BB-digest V8 324
Path: IZ3LSV<IK2XDE<ON4HU<CX2ACB<CX2SA
Sent: 130922/1901Z @:CX2SA.SAL.URY.SA #:11394 [Salto] FBB7.00e $:AMSATBB8324
From: CX2SA@CX2SA.SAL.URY.SA
To : SATDIG@WW
Today's Topics:
1. Re: Phase 3 (Gordon JC Pearce)
2. Re: Phase 3 (i8cvs)
3. Re: Phase 3 (i8cvs)
4. Re: Phase 3 (Peter Guelzow)
5. FL11 active in SO-50 in the two morning passes
(Pavel Milanes Costa)
6. Cygnus Berthing To ISS Delayed (B J)
7. Re: Phase 3 (R Oler)
8. Cygnus Docking Delayed 48 Hours (Clint Bradford)
9. Re: Phase 3 (Daniel Schultz)
10. Re: Phase 3 (Daniel Schultz)
----------------------------------------------------------------------
Message: 1
Date: Sun, 22 Sep 2013 10:50:32 +0100
From: Gordon JC Pearce <gordonjcp@xxxx.xxx>
To: amsat-bb@xxxxx.xxx
Subject: [amsat-bb] Re: Phase 3
Message-ID: <20130922095032.GA30306@xxxx.xxx>
Content-Type: text/plain; charset=us-ascii
On Sat, Sep 21, 2013 at 11:26:08PM -0400, Daniel Schultz wrote:
> That's what Cubesats offer... ability to launch "off the shelf" satellites
> whenever an opportunity comes along, without having to do detailed
integration
> with the launch vehicle. If only they were not so damn small...
They don't have to be big. Look at the sort of performance you can pack
into a
terrestrial radio these days!
I had a cheapy Chinese HT apart last week for repair (turns out it was
extensively
water-damaged, so it was a write-off) from one of the better cheapy Chinese
manufacturers.
The whole thing was on two thin boards, with the front panel board populated
on both sides
and the RF board mostly only populated on one side, and both boards fit
side-by-side in
the palm of my hand. The 1800mAh LiPoly battery was about the size of two
Compactflash
cards, and (when they haven't been drowned) run it for a full day of heavy
use.
Now the cheapy Chinese radios are often criticised for poor spec, but these
have a lovely
clean output spectrum, solid 4W output and a 12dB SINAD down about -120dBm
so you can't
really fault them for that - tracking RF filters so the front end is good
and tight too -
so they must be doing something right.
The boards weigh about 50 grammes.
You could conceivably rip the RF board out of a UHF and VHF one and couple
it with your
own CPU and audio board, and have a ~150 gramme mode V/U transponder on a
standard 10x10
cubesat board. You could use a 10m SDR and a wee DSP board like the ones
that TI does for
a few beer tokens and build Bob Bruniga's crossband PSK transponder. You
could do all
this for the price of the buffet for four and a couple of pints at my local
Indian
restaurant, and you could do it in a weekend.
You can cram a lot of radio into a tiny space these days, and with a cubesat
you've got a
bit of space about the size and weight of a bag of sugar. You could just
about tape two
big old Motorola GP340s together and fit them in a 2U launch. There's no
excuse. Yes,
the components are expensive (have you seen the price of a cubesat chassis?)
but with
enough people working on it we'll figure out a more affordable way to build
a flight-rated
cube.
First though, we need to stop bloody moaning about AO40.
--
Gordonjcp MM0YEQ
------------------------------
Message: 2
Date: Sun, 22 Sep 2013 12:26:57 +0200
From: "i8cvs" <domenico.i8cvs@xxx.xx>
To: "Daniel Schultz" <n8fgv@xxx.xxx>, "Amsat - BBs"
<amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Re: Phase 3
Message-ID: <000901ceb77e$45e6f7d0$0301a8c0@xxxxx>
Content-Type: text/plain; charset="iso-8859-1"
----- Original Message -----
From: "Daniel Schultz" <n8fgv@xxx.xxx>
To: <amsat-bb@xxxxx.xxx>
Sent: Sunday, September 22, 2013 5:26 AM
Subject: [amsat-bb] Re: Phase 3
> >> Could a 3U cubesat with deployable solar panels power a 1 watt,
> >> 100 kHz, mode U/V transponder?
>
> Yes, I believe that is possible, with deployable arrays we might even be
> able to do ten watts, but such a tiny satellite in such a high orbit will
> require big antennas on the ground just to hear it. I can already hear the
> cries on amsat-bb about the "elitists" who want to push the little guys
> out of the satellite game so they can keep the HEO satellite all to
> themselves.
>
> Dan Schultz N8FGV
>
Hi Dan, N8FGV
You are correct because remember OSCAR-13 carried on a U/V
transponder with 50 watt pep and a 2 meters RHCP antenna with
10 dBi gain.
Now if a 3U cubesat with deployable solar panels has a U/V transponder
with 1 watt power the difference in EIRP between OSCAR-13 and the
above 3U cubesat only considering power is:
10 log (50/1 ) = 17 dB
10
Now consider that the average of OSCAR-13 ground station were using
2 meters crossed dipole antennas with 13 dBi gain and you will see that
to receive the downlink of the above 3U cubesat with the same S/N ratio
of OSCAR-13 you must use a 2 meter crossed dipole antenna with
13+17 = 30 dBi gain i.e. an EME antenna.
Now consider that is possible, with deployable arrays we might even
be able to get ten watt from the 3U cubesat than the difference in EIRP
between OSCAR-13 and the above 3U cubesat only considering power is:
10 log (50/10 ) = 7 dB and you will see that to receive the downlink
10
of the above 3U cubesat with the same S/N ratio of OSCAR-13 you
must use a 2 meter antenna with 13+7 = 20 dBi gain i.e. an array of
four antennas with gain of 13 dBi each wich is convenient only for
those amateurs working EME
I don't know what could be the 2 meters antenna gain on board of a
3U cubesat but I believe not more than the gain of a crossed dipole i.e.
2.14 dBi wich do not change significantly the above budged situation
in order to reduce the gain of the 2 meters ground station antennas.
We will talk about on the phone as soon you will be in Naples in the
next few days from 28 September to 1 October
73" de i8CVS Domenico
------------------------------
Message: 3
Date: Sun, 22 Sep 2013 12:29:41 +0200
From: "i8cvs" <domenico.i8cvs@xxx.xx>
To: "AMSAT-BB" <amsat-bb@xxxxx.xxx>, "pabutusa@xxxxx.xxxx
<rob@xxxxx.xxx>
Subject: [amsat-bb] Re: Phase 3
Message-ID: <001301ceb77e$a7063fd0$0301a8c0@xxxxx>
Content-Type: text/plain; charset="iso-8859-1"
----- Original Message -----
From: "pabutusa@xxxxx.xxxx <rob@xxxxx.xxx>
To: "i8cvs" <domenico.i8cvs@xxx.xx>
Sent: Sunday, September 22, 2013 5:01 AM
Subject: Re: [amsat-bb] Re: Phase 3
Are you sure the kick motors on ao10/13 were solid ???? I was pretty sure
the were liquid because the could be fired multiple times to tweak the
orbit. I also remember seeing pictures of technicians I'm hazmat suits
fueling the bird.
--> Rob, ka2pbt
Hi Rob,KA2PBT
The solid propellant motor of OSCAR-10 was designed to fire
only one time at the apogee and change the orbit inclination to
around 67 degrees into a Molniya orbit but unfortunately the
onboard 400 Newton kick motor did not function entirely
correctly, due to collision with launch vehicle after separation
- hence the not-quite-Molniya-orbit with only inclination of
27 degrees.
OSCAR-13 uses a bi-propellant hydrazine and nitrous oxide
400 Newton motor system and behaved flawlessly during the
two post launch burns.
Oscar-13 was launched into a highly elliptical equatorial orbit,
a "Geostationary Transfer Orbit", with a perigee height of
240 km. Over the next 7 days it was re-oriented to point the motor
along-track such that apogee velocity could be increased by
150 m/s. This increased perigee height to 1100 km, and freed
the satellite from buffeting and atmospheric drag.
During the next 2 weeks it was oriented "upwards" so that a burn
at apogee would increase inclination to 58?, and perigee height to
2500 km.
Two weeks later, 1988 July 22 15:00 utc the mode-B transponder
was switched on for general use.
The pictures you have seen referes to charge the fluid bi-propellant
hydrazine and nitrous oxide toxic fuel into OSCAR-13 and later
on to charge the liquid propellant into AO40 made with UMDH
and nitrogen tetroxide.
73" de
i8CVS Domenico
On Sep 21, 2013, at 22:15, "i8cvs" <domenico.i8cvs@xxx.xx> wrote:
> ----- Original Message -----
> From: "Angus McLeod" <amcleod@xxxxxxxxx.xxx>
> To: <amsat-bb@xxxxx.xxx>
> Sent: Saturday, September 21, 2013 9:27 PM
> Subject: [amsat-bb] Re: Phase 3
>
>
>> As far as I know, the kick-motors used on the Phase-3 birds were NOT
>> cardboard tubes packed with homemade gunpowder. They were commercial
>> grade motors obtained from the commercial aerospace industry. If I am
>> wrong about this, and someone can jump in with facts, I'd be glad to
>> hear.
>
>
> Hi Angus,
>
> The kitch apogee motors for OSCAR-10,and OSCAR-13 were solid propellant
> 400 Newton trust motors donated to AMSAT-DL by the Messerschmitt Aerospace
> Company in Germany.
>
> The kick apogee motor for AO40 was a liquid propellant made with UMDH and
> nitrogen tetroxide but it failed to work because unfortunately someone
> before the flight forgot to remove the safety red cover over the exost
> valve of the fuel system and this is why after many attemps to overcome
> the problem the satellite got an explosion inside wich damaged most part
> of transponders.BTW AO40 worked fantastic in Mode U/S ,Mode L/S
> and Mode L/K for a long time until the main battery and the spare battery
> system suddently failed in short circuit.
>
> 73" de i8CVS Domenico
>
>
> _______________________________________________
> Sent via AMSAT-BB@xxxxx.xxx. 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
------------------------------
Message: 4
Date: Sun, 22 Sep 2013 13:33:17 +0200
From: Peter Guelzow <peter.guelzow@xxxxxx.xx>
To: amsat-bb@xxxxx.xxx
Subject: [amsat-bb] Re: Phase 3
Message-ID: <523ED57D.4040408@xxxxxx.xx>
Content-Type: text/plain; charset=ISO-8859-1
Hi Domenico, et all,
OSCAR-10 (P3-B) used the same 400N engine as OSCAR-13 (P3-C) and
OSCAR-40 (P3-D).
For P3-E we have a 200N motor from EADS Astrium, the same one which is
used on the European ATV...
I was AMSAT P3-A (planned to be OSCAR-9) which used a solid propellant
apogee kick-motor.
It's under the water near the cost of french Guiana.. RIP
You can find an very good article here:
http://www.ka9q.net/AMSAT-Tech-Journal-2.pdf
See page 8..15
Rest assured, the PFA and propulsion system was qualified according to
highest commercial standards by commercial companies. Thus in no way
there would be any risk to the launcher or other payloads. This also
includes several levels of safety borders in the hardware design and in
the software. The launch agencies have there own specialized personal
to review all the details... Without that, nobody would have launched
any of the P3 satellites !!!
What happened to AO-40 later on after orbit injection and after
activating the systems is a completely different matter and did not
present any risk to the launcher at any time!
73s Peter DB2OS
On 22.09.2013 12:29, i8cvs wrote:
> ----- Original Message -----
> From: "pabutusa@xxxxx.xxxx <rob@xxxxx.xxx>
> To: "i8cvs" <domenico.i8cvs@xxx.xx>
> Sent: Sunday, September 22, 2013 5:01 AM
> Subject: Re: [amsat-bb] Re: Phase 3
>
> Are you sure the kick motors on ao10/13 were solid ???? I was pretty sure
> the were liquid because the could be fired multiple times to tweak the
> orbit. I also remember seeing pictures of technicians I'm hazmat suits
> fueling the bird.
>
> --> Rob, ka2pbt
>
> Hi Rob,KA2PBT
>
> The solid propellant motor of OSCAR-10 was designed to fire
> only one time at the apogee and change the orbit inclination to
> around 67 degrees into a Molniya orbit but unfortunately the
> onboard 400 Newton kick motor did not function entirely
> correctly, due to collision with launch vehicle after separation
> - hence the not-quite-Molniya-orbit with only inclination of
> 27 degrees.
>
> OSCAR-13 uses a bi-propellant hydrazine and nitrous oxide
> 400 Newton motor system and behaved flawlessly during the
> two post launch burns.
>
> Oscar-13 was launched into a highly elliptical equatorial orbit,
> a "Geostationary Transfer Orbit", with a perigee height of
> 240 km. Over the next 7 days it was re-oriented to point the motor
> along-track such that apogee velocity could be increased by
> 150 m/s. This increased perigee height to 1100 km, and freed
> the satellite from buffeting and atmospheric drag.
>
> During the next 2 weeks it was oriented "upwards" so that a burn
> at apogee would increase inclination to 58?, and perigee height to
> 2500 km.
>
> Two weeks later, 1988 July 22 15:00 utc the mode-B transponder
> was switched on for general use.
>
> The pictures you have seen referes to charge the fluid bi-propellant
> hydrazine and nitrous oxide toxic fuel into OSCAR-13 and later
> on to charge the liquid propellant into AO40 made with UMDH
> and nitrogen tetroxide.
>
> 73" de
>
> i8CVS Domenico
>
> On Sep 21, 2013, at 22:15, "i8cvs" <domenico.i8cvs@xxx.xx> wrote:
>
>> ----- Original Message -----
>> From: "Angus McLeod" <amcleod@xxxxxxxxx.xxx>
>> To: <amsat-bb@xxxxx.xxx>
>> Sent: Saturday, September 21, 2013 9:27 PM
>> Subject: [amsat-bb] Re: Phase 3
>>
>>
>>> As far as I know, the kick-motors used on the Phase-3 birds were NOT
>>> cardboard tubes packed with homemade gunpowder. They were commercial
>>> grade motors obtained from the commercial aerospace industry. If I am
>>> wrong about this, and someone can jump in with facts, I'd be glad to
>>> hear.
>>
>> Hi Angus,
>>
>> The kitch apogee motors for OSCAR-10,and OSCAR-13 were solid propellant
>> 400 Newton trust motors donated to AMSAT-DL by the Messerschmitt Aerospace
>> Company in Germany.
>>
>> The kick apogee motor for AO40 was a liquid propellant made with UMDH and
>> nitrogen tetroxide but it failed to work because unfortunately someone
>> before the flight forgot to remove the safety red cover over the exost
>> valve of the fuel system and this is why after many attemps to overcome
>> the problem the satellite got an explosion inside wich damaged most part
>> of transponders.BTW AO40 worked fantastic in Mode U/S ,Mode L/S
>> and Mode L/K for a long time until the main battery and the spare battery
>> system suddently failed in short circuit.
>>
>> 73" de i8CVS Domenico
>>
>>
>> _______________________________________________
>> Sent via AMSAT-BB@xxxxx.xxx. 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@xxxxx.xxx. 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
>
------------------------------
Message: 5
Date: Sun, 22 Sep 2013 08:06:57 -0400
From: Pavel Milanes Costa <co7wt@xxxxxx.xx.xx>
To: amsat-bb@xxxxx.xxxx "Hector L Martinez, CO6CBF"
<co6cbf@xxxxxx.xx.xx>, Raidel Abreu Espinet <cm2esp@xxxxxx.xx.xx>
Subject: [amsat-bb] FL11 active in SO-50 in the two morning passes
Message-ID: <523EDD61.2090009@xxxxxx.xx.xx>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Hi to all... from CO7WT
I will try to be active in the two morning passes of SO-50, it will be
mobile from a outside location as a part of my radio club activities...
(I will be demonstrating satellite communications)
No way of recording so far... I will have a secretary writing down
callsigns that have not so much practice in english... So if some one
can record the pass I will appreciate the mp3 file...
As the time is passing I see more the second morning pass... because we
have to setup a HF station, etc..
73
------------------------------
Message: 6
Date: Sun, 22 Sep 2013 14:08:56 +0000
From: B J <va6bmj@xxxxx.xxx>
To: amsat-bb <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Cygnus Berthing To ISS Delayed
Message-ID:
<CAP7QzkMQUeuj34xFR7_oObfYmum7uHB1m3ZJ1qOPtLTSdcwf=A@xxxx.xxxxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1
http://www.nasaspaceflight.com/2013/09/cygnus-cots-graduation-iss-berthing/
http://www.parabolicarc.com/2013/09/22/cygnus-rendezvous-delayed-48-hours/
73s
Bernhard VA6BMJ @ DO33FL
------------------------------
Message: 7
Date: Sun, 22 Sep 2013 08:19:28 +0600
From: R Oler <orbitjet@xxxxxxx.xxx>
To: Angus McLeod <amcleod@xxxxxxxxx.xxx>
Cc: "amsat-bb@xxxxx.xxxx <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Re: Phase 3
Message-ID: <BLU403-EAS392BF4757193370D0F51F8DD62C0@xxx.xxx>
Content-Type: text/plain; charset="us-ascii"
The people installing them and safing them and all the other things were
mostly not rocket scientist that is why somewhere on AO-40 there is a
"remove before flight" what we call in the business "flag" flying RGO
Sent from my iPad
> On Sep 22, 2013, at 1:55 AM, "Angus McLeod" <amcleod@xxxxxxxxx.xxx> wrote:
>
> As far as I know, the kick-motors used on the Phase-3 birds were NOT
cardboard tubes packed with homemade gunpowder. They were commercial grade
motors obtained from the commercial aerospace industry. If I am wrong about
this, and someone can jump in with facts, I'd be glad to hear.
>
>
>> On 09/21/2013 05:48 AM, Gordon JC Pearce wrote:
>>> On Fri, Sep 20, 2013 at 11:23:29PM +0600, R Oler wrote:
>>> While anything is possible I will be very surprised (pleasntly) if there
is another amateur radio satellite with a liquid propulsion system that is
managed by any amateur group that gets a ride into any sort of HEO transfer
orbit.Ion engines might be different but after AO-40 and its propulsion
issues the days of amateurs playing with rocket engines on commercial
flights I suspect is over.
>> This is something I've often wondered about. "Oh hi, commercial rocket
company, can we stick our homebrewed rocket into your billion dollar vehicle?"
>>
>> When people with more oil than weapons stuff some mix of chemicals into a
tube and crimp the end shut it's called an Improvised Explosive Device.
We're supposed to somehow convince someone to let us tack our semitested
bomb onto their flight? I doubt they're going to go for it...
>
> _______________________________________________
> Sent via AMSAT-BB@xxxxx.xxx. 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
------------------------------
Message: 8
Date: Sun, 22 Sep 2013 09:46:48 -0700
From: Clint Bradford <clintbrad4d@xxxxxxxxx.xxx>
To: amsat-bb@xxxxx.xxx
Subject: [amsat-bb] Cygnus Docking Delayed 48 Hours
Message-ID: <DC674E8B-059D-4BD2-BF39-31E2CA4D310D@xxxxxxxxx.xxx>
Content-Type: text/plain; charset=us-ascii
Cygnus Rendezvous Delayed 48 Hours
Sept 22, 2013
Orbital Sciences has confirmed Sunday morning, around 1:30 a.m. EDT, its
Cygnus spacecraft established direct data contact with the International
Space Station (ISS) and found that some of the data received had values that
it did not expect, causing Cygnus to reject the data. This mandated an
interruption of the approach sequence. Orbital has subsequently found the
causes of this discrepancy and is developing a software fix. The minimum
turnaround time to resume the approach to the ISS following an interruption
such as this is approximately 48 hours due to orbital mechanics of the
approach trajectory.
-NASA.gov
------------------------------
Message: 9
Date: Sun, 22 Sep 2013 14:34:32 -0400
From: "Daniel Schultz" <n8fgv@xxx.xxx>
To: <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Re: Phase 3
Message-ID: <191RiVshG1536S01.1379874872@xxxxx.xxx.xxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1
Gordonjcp MM0YEQ wrote:
>>You could conceivably rip the RF board out of a UHF and VHF one and couple
it
>>with your own CPU and audio board, and have a ~150 gramme mode V/U
transponder
>>on a standard 10x10 cubesat board. You could use a 10m SDR and a wee DSP
board
>>like the ones that TI does for a few beer tokens and build Bob Bruniga's
>>crossband PSK transponder. You could do all this for the price of the
buffet
>>for four and a couple of pints at my local Indian restaurant, and you could
do
>>it in a weekend.
>>You can cram a lot of radio into a tiny space these days, and with a
cubesat
>>you've got a bit of space about the size and weight of a bag of sugar. You
>>could just about tape two big old Motorola GP340s together and fit them in a
2U
>>launch. There's no excuse.
I agree that you can pack a lot of electronics into small packages these days.
I disagree that it is feasible to use commercial radios that were not
engineered for space flight. Many student groups have in fact used HT guts for
their LEO beepsats but if you want a mission that lasts ten years instead of
six months, you need to do some serious engineering.
The reason why Cubesats are too damn small is not about the electronics inside
the cube, but the questions you need to ask are:
Can the satellite deploy enough solar cells to generate sufficient electrical
power?
can the satellite deploy a large enough antenna to direct a usable signal to
users on Earth?
Can you keep that antenna pointed at the Earth, at the same time that you are
keeping the solar array pointed at the sun?
Is there sufficient external area on the satellite to radiate waste heat from
the electronics?
A Cubesat with a Chinese HT inside and 100 square centimeters of solar cells
on all six surfaces can generate one or two watts into a whip antenna, but put
one of those in high altitude orbit, 10,000 km from Earth, and only hams with
EME class stations will be able to make use of it.
This is the reason why LEO Cubesats are easy and HEO Cubesats are hard.
I appreciate the motivational stories about deaf frogs who don't know what is
impossible, but sometimes you do have to pay attention to the ugly laws of
physics. That's why someone once defined an Engineer as a "Disciplined
Dreamer". One of my favorite New Yorker cartoons was of a motivational speaker
standing in front of a room full of people wearing Superman costumes, telling
them "Now go out there and fly!". I guess that's the reason why Superman
Halloween costumes come with a warning on the box that "wearing this cape will
not allow you to fly"...
Dan Schultz N8FGV
------------------------------
Message: 10
Date: Sun, 22 Sep 2013 14:43:34 -0400
From: "Daniel Schultz" <n8fgv@xxx.xxx>
To: <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Re: Phase 3
Message-ID: <177RiVsQI9552S07.1379875414@xxxxx.xxx.xxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1
>>The apogee motors for OSCAR-10,and OSCAR-13 were solid propellant
>>400 Newton trust motors donated to AMSAT-DL by the Messerschmitt Aerospace
>>Company in Germany.
Only Phase 3A had a solid fuel motor. AO-10 and AO-13 had liquid fuel
bi-propellent motors the same as AO-40. No matter how well designed they are,
they still have the potential to blow up the entire launch stack if something
goes wrong. Since Dick Daniels is no longer with us, the knowledge has been
lost and we will not be launching any more of these in the future.
Dan Schultz N8FGV
------------------------------
_______________________________________________
Sent via amsat-bb@xxxxx.xxx. Opinions expressed are those of the author.
Not an AMSAT member? Join now to support the amateur satellite program!
http://amsat.org/mailman/listinfo/amsat-bb
End of AMSAT-BB Digest, Vol 8, Issue 324
****************************************
Read previous mail | Read next mail
| |
