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CX2SA > SATDIG 11.10.11 13:05l 897 Lines 33899 Bytes #999 (0) @ WW
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Today's Topics:
1. Re: Geostationary Satellites (Tony Langdon)
2. Re: Geostationary Satellites (Gordon JC Pearce)
3. Re: Geostationary Satellites (Jim Jerzycke)
4. Re: KickSat - a personal spacecraft of your own in space
(Bill Ress)
5. Re: KickSat - a personal spacecraft of your own in space
(Andy Kellner)
6. Re: Geostationary Satellites (myles landstein)
7. JOTA this weekend (Tom Schuessler)
8. Re: Geostationary Satellites (Paul Williamson)
9. Re: Geostationary Satellites (R Oler)
10. Re: Geostationary Satellites (R Oler)
11. Sat demo on VO-52 (Rodney Waln)
12. Re: Geostationary Satellites (Daniel Schultz)
13. Re: Geostationary Satellites (Tony Langdon)
14. Re: Geostationary Satellites (Ken Ernandes)
----------------------------------------------------------------------
Message: 1
Date: Tue, 11 Oct 2011 10:04:43 +1100
From: Tony Langdon <vk3jed@xxxxx.xxx>
To: Bob- W7LRD <w7lrd@xxxxxxx.xxx>, ka9qjg <ka9qjg@xxxxxx.xxx>
Cc: AMSAT-BB@xxxxx.xxx
Subject: [amsat-bb] Re: Geostationary Satellites
Message-ID: <4e937a16.4a5a340a.315b.25d0@xx.xxxxxx.xxx>
Content-Type: text/plain; charset="iso-8859-1"; format=flowed
At 09:24 AM 10/11/2011, Bob- W7LRD wrote:
>simple reason money money!!? We? should all
>pool our Visa cards and create another AO-40 (sobsob).
Oh, if I had the money, I'd love to chip in
something for another AO-40 like bird, but not so
keen on its originally planned orbit, because
down here, the elevation would have been less
than 20 degrees most of the time, except near
perigee, when there's not a lot of places within
the footprint. I wonder what a good "compromise"
orbital inclination would be for a P3 type
amateur sat. Equatorial orbits make it hard for
higher northern latitudes, while high inclination
orbits make southern hemisphere access more difficult.
73 de VK3JED / VK3IRL
http://vkradio.com
------------------------------
Message: 2
Date: Tue, 11 Oct 2011 00:05:58 +0100
From: Gordon JC Pearce <gordonjcp@xxxx.xxx>
To: amsat-bb@xxxxx.xxx
Subject: [amsat-bb] Re: Geostationary Satellites
Message-ID: <20111011000558.b582fc69.gordonjcp@xxxx.xxx>
Content-Type: text/plain; charset=US-ASCII
On Mon, 10 Oct 2011 18:41:05 -0400
"Tom Schaefer, NY4I" <ny4i@xxxx.xxx> wrote:
> Seriously, you think it gets boring talking to us same guys on AO-51 each
day? Try that for a giant repeater in space.
Talking to the same guys would be nice, but it would never happen.
OLA! OOOOOHLA! OOOOOOHHHHH-LAAAAAAA! OLA! OLA! OOOOOOHLAAAAAAA! <whistle>
<whistle> OLA! <whistle> <whistle> OOOOOOHLAAAAA! OLA! <whistle>
--
Gordon JC Pearce MM0YEQ <gordonjcp@xxxx.xxx>
------------------------------
Message: 3
Date: Mon, 10 Oct 2011 23:42:37 +0000
From: Jim Jerzycke <kq6ea@xxxxxxx.xxx>
To: "Tom Schaefer, NY4I" <ny4i@xxxx.xxx>
Cc: AMSAT-BB <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Re: Geostationary Satellites
Message-ID: <4E9382ED.30806@xxxxxxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Numbers for just the cost of an Amateur payload, or numbers for the
whole satellite?
A 'typical' satellite costs from 150 million to 300 million, depending
on what hardware it carries.
The cost of a launch to Geosynchronous Transfer Orbit ranges from 95
million to 150 million depending on the launch provider.
Jim KQ6EA
On 10/10/2011 10:41 PM, Tom Schaefer, NY4I wrote:
> Has anyone run the numbers? Are we talking 20 million, 100 million?
>
> Let's see, there are at best 5000 satellite ops. So, if it cost
$20,000,000 we are each in it for $4000. I'm game. Now to convince 4999 of
my friends. :)
>
> Seriously, you think it gets boring talking to us same guys on AO-51 each
day? Try that for a giant repeater in space. That would be wide area. I know
we hear that something like P3D would just cost too much, but this is a lot
of dough to talk to friends across the country at drive time. The wider
orbits make for more interesting conversations. Not that I don;t want to
talk to you every day :)
>
>
> Tom
>
>
> Tom Schaefer, NY4I
> ny4i@xxxx.xxx
> EL88pb
> Monitoring EchoLink node KJ4FEC-L 489389
> DSTAR Capable APRS: NY4I-15
>
>
>
> On Oct 10, 2011, at 5:50 PM, Alan P. Biddle wrote:
>
>> Don,
>>
>> Cost, which is enough to drop any other issues to noise level. That is the
>> High Rent District, and given how much the commercial users pay, they would
>> not want to have an "amateur" satellite wandering around. More
practically,
>> it would be nice to have a package on a commercial satellite. They provide
>> the power, pointing, and control. We just provide the RF. Again, cost,
>> though we have been looking for the right opportunity.
>>
>> Another drawback is that a geosynch only provides coverage to _about_ a
>> third of the earth, and it is always the same third. Birds like AO-13 and
>> AO-40 covered just about all of it over the space of a few days. Did I
>> mention cost? It is fun to think about having 3 which could be linked for
>> true global coverage.
>>
>> Alan
>> WA4SCA
>>
>>
>> -----Original Message-----
>> From: amsat-bb-bounces@xxxxx.xxx [mailto:amsat-bb-bounces@xxxxx.xxxx On
>> Behalf Of ka9qjg
>> Sent: Monday, October 10, 2011 4:23 PM
>> To: AMSAT-BB@xxxxx.xxx
>> Subject: [amsat-bb] Geostationary Satellites
>>
>> Hello Hope Everyone is doing Well, I know people say no such thing as a
dumb
>> question So here goes What is the reason We do not have any Type of
>> geostationary Satellites. Is it because they are for World Wide Use and If
>> stationary one could Hit it 24/7 and Maybe park there butt on it and Run a
>> Beam and Amp and take it over
>>
>>
>>
>> Thanks
>>
>>
>>
>> 73 De Don KA9QJG
>>
>>
>>
>> _______________________________________________
>> 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
>
> _______________________________________________
> 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: Mon, 10 Oct 2011 16:43:47 -0700
From: Bill Ress <bill@xxxxxxxxxxx.xxx>
To: amsat-bb@xxxxx.xxx
Subject: [amsat-bb] Re: KickSat - a personal spacecraft of your own in
space
Message-ID: <4E938333.3050504@xxxxxxxxxxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Aaah Trevor, you raise another important issue!
It is the convention (I can't cite the international rules here) that
all communication/telemetry satellites have the ability to be commanded
off. Clearly the Sprites don't presently have that capability.
Additionally, I don't believe that just because they are in the
unlicensed bands, that they would be permitted to use those bands in
space. But I'm not clear here. Perhaps an experimental license could be
granted to operate in space by our FCC but that would only be good over
the US. Again the command/control issue comes into play.
I have had several emails with Zac and he's very receptive to getting
our comments. I also encouraged him to forge ahead while trying to
understand some of these sticky issues. His concept surely would push
the envelope of current Amateur communications and satellite "art" and
that's worthy of this efforts.
What will be interesting is the reported 10 mw telemetry beacon being
used by SRMSAT, since that's the EIRP the Sprite is planning to have. So
a "real" test at that power level is eminent. Good luck on the launch!!!
Regards...Bill - N6GHz
On 10/10/2011 3:07 PM, Trevor . wrote:
> --- On Mon, 10/10/11, Tony Langdon<vk3jed@xxxxx.xxx> wrote:
>> Still seems a strange choice of frequency, given that GSM
>> phones use these frequencies in many parts of the world.
>
> ITU Region 1 seems to be moving closer to permitting unlicensed low power
use, RFID etc, around 915-921 MHz but as you say the rest is mobile phones.
>
> Given there is no mechanism to command these Sprite ChipSats so they are
only on over the USA the use of 902 MHz would seem inapropriate.
>
> 73 Trevor M5AKA
>
> _______________________________________________
> 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: Mon, 10 Oct 2011 17:33:07 -0700 (PDT)
From: Andy Kellner <hawat1@xxxxx.xxx>
To: "amsat-bb@xxxxx.xxxx <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Re: KickSat - a personal spacecraft of your own in
space
Message-ID:
<1318293187.81436.YahooMailNeo@xxxxxxxxx.xxxx.xxx.xxxxx.xxx>
Content-Type: text/plain; charset=iso-8859-1
All,
just my 2 cents: I think the project is rather interesting and I would be
willingly to sponsor it with my $300 (thats the number I've read to sponsor
my own personal sprite), if -
and thats a big if - I am able to receive and decode the signal with my
average equipped Oscar station.
Something like : Here is the Kepler & Frequency of the Sprite 'cloud'. Track
it with your high-gain low-noise UHF setup, record what you hear and then
use software provided to siff thru the data stream to look for your personal
sponsored sprite, transmitting the message you've submitted. That would be a
cool thing to do / to have and would win me over for sponsorship.
But to sponsor one and then just 'take their word for it' that its up there
and transmitting ? Thats not what the hobby is about IMHO.
BTW: Here is a picture of a prototype, in case you haven't seen it :?
http://news.cnet.com/8301-17938_105-20118335-1/send-your-own-satellite-into-sp
ace/
Andreas - VK4HHH
________________________________
From: Bill Ress <bill@xxxxxxxxxxx.xxx>
To: amsat-bb@xxxxx.xxx
Sent: Tuesday, 11 October 2011 9:43 AM
Subject: [amsat-bb] Re: KickSat - a personal spacecraft of your own in space
Aaah Trevor, you raise another important issue!
It is the convention (I can't cite the international rules here) that all
communication/telemetry satellites have the ability to be commanded off.
Clearly the Sprites don't presently have that capability.
Additionally, I don't believe that just because they are in the unlicensed
bands, that they would be permitted to use those bands in space. But I'm not
clear here. Perhaps an experimental license could be granted to operate in
space by our FCC but that would only be good over the US. Again the
command/control issue comes into play.
I have had several emails with Zac and he's very receptive to getting our
comments. I also encouraged him to forge ahead while trying to understand
some of these sticky issues. His concept surely would push the envelope of
current Amateur communications and satellite "art" and that's worthy of this
efforts.
What will be interesting is the reported 10 mw telemetry beacon being used
by SRMSAT, since that's the EIRP the Sprite is planning to have. So a "real"
test at that power level is eminent. Good luck on the launch!!!
Regards...Bill - N6GHz
On 10/10/2011 3:07 PM, Trevor . wrote:
> --- On Mon, 10/10/11, Tony Langdon<vk3jed@xxxxx.xxx>? wrote:
>> Still seems a strange choice of frequency, given that GSM
>> phones use these frequencies in many parts of the world.
>
> ITU Region 1 seems to be moving closer to permitting unlicensed low power
use, RFID etc, around 915-921 MHz? but as you say the rest is mobile phones.
>
> Given there is no mechanism to command these Sprite ChipSats so they are
only on over the USA the use of 902 MHz would seem inapropriate.
>
> 73 Trevor M5AKA
>
> _______________________________________________
> 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: 6
Date: Mon, 10 Oct 2011 21:21:28 -0400
From: myles landstein <myles.landstein@xxxxx.xxx>
To: Jim Jerzycke <kq6ea@xxxxxxx.xxx>
Cc: amsat-bb BB <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Re: Geostationary Satellites
Message-ID: <55D22C72-CD54-4561-9981-43D983111407@xxxxx.xxx>
Content-Type: text/plain; charset=us-ascii
I am 300million short and have no experience raising capital, but if (and
I guess there isn't any way for hams to raise 300mil), there was, I'd
volunteer to do as much as I could ...
Maybe that means soldering boards all night, or passing out a tin cup
for donations ....
but I'd do what I could...as a volunteer
maybe one day something will make going geo possible <shrugs>
Was that estimated 300mil for the entire bird? Would it be less to
just be a package (perhaps of a few) on a commercial sat?
N2EHG
On Oct 10, 2011, at 7:42 PM, Jim Jerzycke wrote:
> Numbers for just the cost of an Amateur payload, or numbers for the whole
satellite?
>
> A 'typical' satellite costs from 150 million to 300 million, depending on
what hardware it carries.
>
> The cost of a launch to Geosynchronous Transfer Orbit ranges from 95
million to 150 million depending on the launch provider.
>
> Jim KQ6EA
>
> On 10/10/2011 10:41 PM, Tom Schaefer, NY4I wrote:
>> Has anyone run the numbers? Are we talking 20 million, 100 million?
>>
>> Let's see, there are at best 5000 satellite ops. So, if it cost
$20,000,000 we are each in it for $4000. I'm game. Now to convince 4999 of
my friends. :)
>>
>> Seriously, you think it gets boring talking to us same guys on AO-51 each
day? Try that for a giant repeater in space. That would be wide area. I know
we hear that something like P3D would just cost too much, but this is a lot
of dough to talk to friends across the country at drive time. The wider
orbits make for more interesting conversations. Not that I don;t want to
talk to you every day :)
>>
>>
>> Tom
>>
>>
>> Tom Schaefer, NY4I
>> ny4i@xxxx.xxx
>> EL88pb
>> Monitoring EchoLink node KJ4FEC-L 489389
>> DSTAR Capable APRS: NY4I-15
>>
>>
>>
>> On Oct 10, 2011, at 5:50 PM, Alan P. Biddle wrote:
>>
>>> Don,
>>>
>>> Cost, which is enough to drop any other issues to noise level. That is
the
>>> High Rent District, and given how much the commercial users pay, they
would
>>> not want to have an "amateur" satellite wandering around. More
practically,
>>> it would be nice to have a package on a commercial satellite. They
provide
>>> the power, pointing, and control. We just provide the RF. Again, cost,
>>> though we have been looking for the right opportunity.
>>>
>>> Another drawback is that a geosynch only provides coverage to _about_ a
>>> third of the earth, and it is always the same third. Birds like AO-13 and
>>> AO-40 covered just about all of it over the space of a few days. Did I
>>> mention cost? It is fun to think about having 3 which could be linked for
>>> true global coverage.
>>>
>>> Alan
>>> WA4SCA
>>>
>>>
>>> -----Original Message-----
>>> From: amsat-bb-bounces@xxxxx.xxx [mailto:amsat-bb-bounces@xxxxx.xxxx On
>>> Behalf Of ka9qjg
>>> Sent: Monday, October 10, 2011 4:23 PM
>>> To: AMSAT-BB@xxxxx.xxx
>>> Subject: [amsat-bb] Geostationary Satellites
>>>
>>> Hello Hope Everyone is doing Well, I know people say no such thing as a
dumb
>>> question So here goes What is the reason We do not have any Type of
>>> geostationary Satellites. Is it because they are for World Wide Use and If
>>> stationary one could Hit it 24/7 and Maybe park there butt on it and Run a
>>> Beam and Amp and take it over
>>>
>>>
>>>
>>> Thanks
>>>
>>>
>>>
>>> 73 De Don KA9QJG
>>>
>>>
>>>
>>> _______________________________________________
>>> 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
>>
>> _______________________________________________
>> 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: 7
Date: Mon, 10 Oct 2011 20:40:19 -0500
From: "Tom Schuessler" <tjschuessler@xxxxxxx.xxx>
To: <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] JOTA this weekend
Message-ID: <001e01cc87b6$bc6ba2b0$3542e810$@xxx>
Content-Type: text/plain; charset=US-ASCII
Jamboree on the Air is the annual joint activity between Scouting and Ham
Radio. Held worldwide for 48 hours on October 15th and 16th. Many Amateur
Radio groups all over the world will be helping Scouts and Guides make
contacts via various modes and bands, including our satellites.
I will again be managing the JOTA effort at the National Scouting Museum in
Irving, Texas using call K2BSA/5. Although this is a daytime only operation
Saturday, we hope to run SSB and FM passes of VO-52, AO-27 and AO-51 as well
as tracking some beacon passes. Unfortunately there are no good ISS passes
for our part of the US during the daytime hours.
My encouragement to the satellite community is to please give way to any of
these JOTA groups you might hear throughout the weekend. We have a
wonderful opportunity to influence the upcoming generation of potential Hams
and successful JOTA contacts work toward that end.
In short, Let the Scouts have the birds this weekend, or at least, give a
JOTA station a call. You will be glad you did and the Scouts will be quite
impressed.
Tom Schuessler
2713 Lake Gardens Drive
Irving, Texas 75060
972-986-7456
214-403-1464 (Cell)
n5hyp@xxxx.xxx
------------------------------
Message: 8
Date: Mon, 10 Oct 2011 19:59:43 -0700
From: Paul Williamson <kb5mu@xxxxx.xxx>
To: Ken Ernandes <n2wwd@xxxxxxxxxx.xxx>
Cc: AMSAT-BB <AMSAT-BB@xxxxx.xxx>
Subject: [amsat-bb] Re: Geostationary Satellites
Message-ID: <9412F76D-C0C9-4B76-A09E-4FC5AB5247FD@xxxxx.xxx>
Content-Type: text/plain; charset=us-ascii
On Oct 10, 2011, at 3:03 PM, Ken Ernandes wrote:
> 1. There are a finite number of orbital slots at Geostationary. That is
essentially like water front property.
I've heard that asserted before, but I question the reasoning.
My understanding is that spacing of satellites around the geostationary
orbit is dictated by the beamwidth of the ground station antennas. In other
words, it's a matter of spatial frequency sharing. The satellites have to be
far enough apart that a ground station antenna can illuminate one of them
without causing too much harmful interference to the ones in the adjacent
slots, after all the expected errors (orbital and ground station pointing)
are taken into account.
If that's correct, since amateur radio satellite operate on different
frequencies from the commercial satellites, there is no conflict between
amateur radio satellites and commercial satellites for orbital slots.
Where have I gone wrong?
73 -Paul
kb5mu@xxxxx.xxx
------------------------------
Message: 9
Date: Mon, 10 Oct 2011 21:19:25 -0500
From: R Oler <orbitjet@xxxxxxx.xxx>
To: <whiteld@xxx.xxx>, <ka9qjg@xxxxxx.xxx>, Amsat BB
<amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Re: Geostationary Satellites
Message-ID: <COL106-W443498AB5ADFE6828410A8D6E20@xxx.xxx>
Content-Type: text/plain; charset="iso-8859-1"
What we need is Arsene or an Oscar IV in the correct orbit...Robert WB5MZO
Life member ARRL AMSAT NARS
> Date: Mon, 10 Oct 2011 16:40:37 -0500
> From: whiteld@xxx.xxx
> To: ka9qjg@xxxxxx.xxxx AMSAT-BB@xxxxx.xxx
> Subject: [amsat-bb] Re: Geostationary Satellites
>
> Short answer: Money. They are much more expensive than the little LEO's,
> CubeSat's, etc.
>
> 73,
>
> Lowell
> K9LDW
>
>
> ------ Original Message ------
> Received: Mon, 10 Oct 2011 04:27:53 PM CDT
> From: "ka9qjg" <ka9qjg@xxxxxx.xxx>
> To: <AMSAT-BB@xxxxx.xxx>
> Subject: [amsat-bb] Geostationary Satellites
>
> > Hello Hope Everyone is doing Well, I know people say no such thing as a
> dumb
> > question So here goes What is the reason We do not have any Type of
> > geostationary Satellites. Is it because they are for World Wide Use and If
> > stationary one could Hit it 24/7 and Maybe park there butt on it and Run a
> > Beam and Amp and take it over
> >
> >
> >
> > Thanks
> >
> >
> >
> > 73 De Don KA9QJG
> >
> >
> >
> > _______________________________________________
> > 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: 10
Date: Mon, 10 Oct 2011 22:53:23 -0500
From: R Oler <orbitjet@xxxxxxx.xxx>
To: <kb5mu@xxxxx.xxx>, <n2wwd@xxxxxxxxxx.xxx>
Cc: Amsat BB <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Re: Geostationary Satellites
Message-ID: <COL106-W276A66EB117DD8E32E9318D6E20@xxx.xxx>
Content-Type: text/plain; charset="iso-8859-1"
There are "radio" considerations and then there are "traffic" considerations
as well...
The odds of amateur radio getting a dedicated geo bird in the belt are next
to nothing. a "drifter" (one above or below the belt) is more
possible...and it is a good orbit for hamsats...Robert G. Oler WB5MZO ARRL
AMSAT NARS life member
> From: kb5mu@xxxxx.xxx
> Date: Mon, 10 Oct 2011 19:59:43 -0700
> To: n2wwd@xxxxxxxxxx.xxx
> CC: AMSAT-BB@xxxxx.xxx
> Subject: [amsat-bb] Re: Geostationary Satellites
>
> On Oct 10, 2011, at 3:03 PM, Ken Ernandes wrote:
> > 1. There are a finite number of orbital slots at Geostationary. That
is essentially like water front property.
>
> I've heard that asserted before, but I question the reasoning.
>
> My understanding is that spacing of satellites around the geostationary
orbit is dictated by the beamwidth of the ground station antennas. In other
words, it's a matter of spatial frequency sharing. The satellites have to be
far enough apart that a ground station antenna can illuminate one of them
without causing too much harmful interference to the ones in the adjacent
slots, after all the expected errors (orbital and ground station pointing)
are taken into account.
>
> If that's correct, since amateur radio satellite operate on different
frequencies from the commercial satellites, there is no conflict between
amateur radio satellites and commercial satellites for orbital slots.
>
> Where have I gone wrong?
>
> 73 -Paul
> kb5mu@xxxxx.xxx
>
>
> _______________________________________________
> 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: 11
Date: Mon, 10 Oct 2011 22:32:05 -0700 (PDT)
From: Rodney Waln <kc0zhf@xxxxx.xxx>
To: "amsat-bb@xxxxx.xxxx <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Sat demo on VO-52
Message-ID:
<1318311125.73818.YahooMailNeo@xxxxxxxx.xxxx.xxx.xxxxx.xxx>
Content-Type: text/plain; charset=iso-8859-1
hi, i know it is short notice but i have been asked to do a SAT demo during
a ham meeting tommarrow,
10-12-2011/ 0137z the only pass that lines up with that time is VO-52 i will
be around 145.910 USB
if possable give me a shout, i will be working portable from the?rare DN71
grid HI HI,
Rodney, kc0zhf
WY Amsat area Coordinator
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Message: 12
Date: Tue, 11 Oct 2011 02:02:43 -0400
From: "Daniel Schultz" <n8fgv@xxx.xxx>
To: <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Re: Geostationary Satellites
Message-ID: <107PJkgBr3472S03.1318312963@xxxxx.xxx.xxx.xxx>
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It is true that a Geo bird would only cover 1/3 of the Earth, but it would
ALWAYS be there, with no need for antenna rotors or keps or a computer for
tracking. It would be like picking up a telephone. It would be wonderful for
emergency service in a disaster area. It could provide high speed digital
communications on the amateur microwave bands in places where the internet is
not available.
Geosynchronous orbit slots are allocated by transponder frequency. On the
amateur radio bands we are free to locate a satellite anywhere we can get to
because we don't share our frequencies with commercial transponders.
The reason we don't have any high altitude satellites is all about the money.
We amateurs created the small satellite business. Back in the old days the big
boys laughed at our cute little toy satellites, but they did allow us to bolt
them to a launch vehicle for free or for very low cost. The experts were
certain that our homebrew satellites wouldn't last a week without expensive
mil-spec electronic components. We amateurs proved that small satellites were
useful and thus created a market that we are now priced out of. The launches
that used to be free can now be sold to paying customers for millions of
dollars. Many of the companies in the small satellite business were founded by
Amsat alumni.
We amateurs are a non-commercial service, by law, with no product or service
that we can sell to raise the $10 million that we would need to buy the sort
of launch that we once got for very cheap. We cannot participate in the market
economy because the law prohibits us from making money from our activity,
which puts us at a huge disadvantage in competing for launches against those
satellite owners who can make money. If future access to space is going to be
limited to those with a good business plan then we might as well pack it in as
satellite builders. The educational-industrial complex has no place for
"amateurs" working alone in their basements and garages without any sort of
formal academic plan and no supervision by management.
Nobody in the commercial or government world cares if we can talk to Japan or
Europe on amateur satellites or collect rare grid squares. It is all about
education, which I am all in favor of except that I question if there really
is such a crying shortage of engineers in the world. The students building
their little Cubesats are going to find out someday that working for Lockheed
Martin or Boeing or NASA is a far, far different world than their experience
in building Cubesats.
The Cubesats are a useless diversion but are popular with the powers that be
because they allow young college students to build a satellite and deliver it
to the launch pad. They are too small to carry the type of payload that we
need to do effective communications in a high altitude orbit. The students and
their sponsors don't care if the satellite actually works on orbit because
they will have graduated by the time it is launched. They recognize that the
world wide network of hams is a valuable resource for tracking and telemetry
collection, but they use amateur radio frequencies without giving back
anything to support the basis and purpose of amateur radio.
If we are ever again going to have high altitude satellites for world wide DX
and supporting high rate digital communications on our amateur microwave bands
we will need to find clever ways to get larger satellites such as Eagle into
higher orbits.
We also screwed up with the failure of AO-40. We could have had 10,000 or more
Amsat members right now if that satellite had worked as designed. Even if we
could raise the bucks to build another one, there is no chance of getting
another Ariane 5 launch. Amsat-DL has not been able to find any launch for the
smaller Phase 3E satellite for any amount of money that we can think about
paying.
The way we did things two decades ago is not how we are going to do things
now. Maybe we will never again have an Amsat-designed and built satellite but
perhaps we can place a transponder on someone else's satellite in return for
some sort of added value to them. There is money available for education
support, maybe we can get some of it if we appeal to the right people. Maybe
we can carry science experiments for NASA or some other agency if we provide
operations support with telemetry and command. Maybe we can tap the same
funding sources that the Google lunar competitors are getting. I don't have
the answers, except that we will need to be just as clever as our predecessors
were 50 years ago if we are ever going to have high altitude, high performance
amateur satellites in our future.
Dan Schultz, N8FGV
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Message: 13
Date: Tue, 11 Oct 2011 17:24:37 +1100
From: Tony Langdon <vk3jed@xxxxx.xxx>
To: "Daniel Schultz" <n8fgv@xxx.xxx>, <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Re: Geostationary Satellites
Message-ID: <4e93e12f.0d06650a.5581.ffff8161@xx.xxxxxx.xxx>
Content-Type: text/plain; charset="us-ascii"; format=flowed
At 05:02 PM 10/11/2011, Daniel Schultz wrote:
>It is true that a Geo bird would only cover 1/3 of the Earth, but it would
>ALWAYS be there, with no need for antenna rotors or keps or a computer for
>tracking. It would be like picking up a telephone. It would be wonderful for
>emergency service in a disaster area. It could provide high speed digital
>communications on the amateur microwave bands in places where the internet is
>not available.
Given that a single bird would most likely be over the Atlantic, a
single GEO bird is of little interest here, compared to something
like a P3 one, which at least shares itself around the world.
73 de VK3JED / VK3IRL
http://vkradio.com
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Message: 14
Date: Tue, 11 Oct 2011 06:31:23 -0400
From: Ken Ernandes <n2wwd@xxxxxxxxxx.xxx>
To: Paul Williamson <kb5mu@xxxxx.xxx>
Cc: AMSAT-BB <AMSAT-BB@xxxxx.xxx>
Subject: [amsat-bb] Re: Geostationary Satellites
Message-ID: <44C4D8C5-537A-4455-B120-F43FCAACFBB9@xxxxxxxxxx.xxx>
Content-Type: text/plain; charset=us-ascii
You are viewing it only from the point of view of signal interference. In
reality, the greater issue is maintaining our position and the risk of
collision. There is a very tight band that defines geostationary and there
are some significant disturbing forces: Earth's triaxial gravity
distribution, lunar and solar gravity, and solar radiation pressure. This
mandates that there be vigilance in monitoring the satellite's orbit and
those of its neighbors and to also have a propulsion system capable of
station-keeping on a regular basis. Even without the risk of collision, not
holding the position tightly nullifies the benefit of fixed antenna pointing.
For those believing in the large space, small satellite theory, the risk of
collision is more real than one might think. I could only imagine the
legislation and regulations that might be placed on amateur satellites if we
failed to control our bird and it collided with a very expensive commercial
or government asset. Until AMSAT can build enough experience to operate a
propulsion system reliably for the long term, I don't think we can
responsibly operate a satellite bus on a congested orbital highway.
73, Ken N2WWD
Sent from my iPad
On Oct 10, 2011, at 10:59 PM, Paul Williamson <kb5mu@xxxxx.xxx> wrote:
> On Oct 10, 2011, at 3:03 PM, Ken Ernandes wrote:
>> 1. There are a finite number of orbital slots at Geostationary. That is
essentially like water front property.
>
> I've heard that asserted before, but I question the reasoning.
>
> My understanding is that spacing of satellites around the geostationary
orbit is dictated by the beamwidth of the ground station antennas. In other
words, it's a matter of spatial frequency sharing. The satellites have to be
far enough apart that a ground station antenna can illuminate one of them
without causing too much harmful interference to the ones in the adjacent
slots, after all the expected errors (orbital and ground station pointing)
are taken into account.
>
> If that's correct, since amateur radio satellite operate on different
frequencies from the commercial satellites, there is no conflict between
amateur radio satellites and commercial satellites for orbital slots.
>
> Where have I gone wrong?
>
> 73 -Paul
> kb5mu@xxxxx.xxx
>
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End of AMSAT-BB Digest, Vol 6, Issue 561
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