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Re: AMSAT UK P3E Lecture HEO vs GEO. and AMSAT-NAPriorities



Hi Joe,

The Eagle ride-share requires no engine from AMSAT as it is supplied by and 
operated by Intelsat. They have an order of magnitude more experience than 
any AMSAT organization and a better track record. It also eliminates more 
than half of the work in building the satellite. That has to reduce risk.

AMSAT-NA members are working on P3E and AMSAT-NA has supplied money for the 
project so I don't see a lack of support.

Since a HEO and GEO are at similar altitudes, I don't forsee a big 
difference in signal strength. The only disadvantage of a GEO for hams is 
that it doesn't move so I can't work India from here as I could on AO-13. 
However, Molniya orbits aren't very useful to outside funders so there is an 
advantage in raising funds. Making satellites hard to use certainly doesn't 
help in rasing money. The aspect of AO-40 that QST pushed during fund-rasing 
was that it would be easier to use than AO-13.

73,

John
KD6OZH

----- Original Message ----- 
From: "Joe Westbrook" <k7zt@suddenlink.net>
To: "John B. Stephensen" <kd6ozh@comcast.net>; <amsat-bb@amsat.org>
Sent: Monday, August 11, 2008 22:06 UTC
Subject: AMSAT UK P3E Lecture HEO vs GEO. and AMSAT-NA Priorities


> John:
> So regarding risk, how many HEO Satellites has AMSAT-NA launched that
> required firing a rocket motor to achieve a Molniya Orbit?
> It seems that AMSAT-DL has the lead on that front, additionally, the
> gentleman that did the PE3 Presentation at the AMSAT-UK Symposium 
> indicated
> that PE3 uses the same platform as AO10 and AO13, and has been tested.  At
> least we have a more predictable risk.  I took a look at the Satellite
> history and it appears that the HEO Flights were all joint ventures with
> AMSAT-NA and AMSAT-DL.  I recall a great deal of publicity in QST
> surrounding the AO40 launch including fund raising activities. Why don't 
> we
> observe the same level of commitment that we had for those projects from
> AMSAT-NA Leadership?.
>
> AO40 provided extraordinary opportunities for the satellite experimenter, 
> it
> wasn't that difficult and was great deal of fun. Additionally, it did push
> the operator to work on improving their station for weak signal work.
> Remember all of the great AO40 how to web sites that popped up?
> Lots of home brew projects! Lots of pictures of stations!
> How many of those are out there for AO51?
>
> I believe for those who endeavored to develop hardware and software 
> definitely
> furthered the science.   I constructed many different antennas and feeds 
> learned a
> great deal all in my back yard with minimal investment using "arm strong" 
> , home-brew az-el  set up.
>
> Regarding GEO vs. HEO, I would argue that in terms of the overall
> experience, there are significant differences that boil down to the
> following::
> 1.  GEO isn't a moving target
> 2.  HEO has a weaker signal
> 3.  With GEO, the antenna is locked down to a fixed Az-EL. No Doppler, no
> need to synchronize the orbit or to integrate software applications.
>
> I would challenge you to tell me how GEO wouldn't be an appliance. What's 
> left
> once you mount your Downconverter, feed, LNA, etc, bring it to your xcvr,
> short of tuning across the transponder to find a clear frequency to call 
> CQ,
> or to locate a contact what's left to do?  I agree that GEO would be great
> for emergencies, nets, and long rag chews on what  will be extremely 
> crowded xponder space.
> Additionally, I think that you would agree that the skill level and 
> overall experience is diminished. But
> that's just me.
>
> All I'm saying is allow the membership vote on how AMSAT-NA resources 
> should
> be used, I don't mean to suggest we vote on the type of RX to use, but on 
> the overall project.
> It is my belief that most members wouldn't want resources diverted to a 
> GEO Project before an HEO Project is fully deployed.
> If we loose sight of the main goal, this process could go on for years.
> To be successful, AMSAT-NA needs a narrow focus as it has very little in 
> the way of resources, both human and financial.
>
> I would be satisfied if AMSAT-NA would simply articulate a clear set of
> goals and priorities, hell even use the survey that was accomplished in 
> 04.
> Communicate these goals to the members at large and finally stand by them.
> If at the end of the day those goals are not what the members want, then
> they can vote with their wallets.
>
> Regards,
> - Joe K7ZT
>
> ----- Original Message ----- 
> From: "John B. Stephensen" <kd6ozh@comcast.net>
> To: "Joe Westbrook" <k7zt@suddenlink.net>; "Luc Leblanc"
> <lucleblanc6@videotron.ca>; <eu-amsat@yahoogroups.com>
> Cc: <amsat-bb@amsat.org>
> Sent: Monday, August 11, 2008 12:12 PM
> Subject: Re: [amsat-bb] Re: [eu-amsat] AMSAT UK P3E Lecture Available
>
>
>> Since AMSAT-DL and AMSAT-NA both require funding from outside the amateur
>> radio community, are going after different sources of funding, and 
>> neither
>> can predict when they will get that funding, having two efforts would 
>> seem
>> to double the opportunity for a non-LEO satellite.
>>
>> I don't think that the risk decreases with P3E. 50% of P3 satellites were
>> lost due to failures of engines in the launch vehicle or in the 
>> satellite.
>>
>> I don't see how having a linear transponder in a geostationary orbit
>> versus a Molniya orbit makes it an appliance satellite. The antennas and
>> transceivers on ground are the same in either case.
>>
>> 73,
>>
>> John
>> KD6OZH
>>
>> ----- Original Message ----- 
>> From: "Joe Westbrook" <k7zt@suddenlink.net>
>> To: "John B. Stephensen" <kd6ozh@comcast.net>; "Luc Leblanc"
>> <lucleblanc6@videotron.ca>; <eu-amsat@yahoogroups.com>
>> Cc: <amsat-bb@amsat.org>
>> Sent: Sunday, August 10, 2008 16:32 UTC
>> Subject: [amsat-bb] Re: [eu-amsat] AMSAT UK P3E Lecture Available
>>
>>
>>> John:
>>> Yes, you may have heard statements like in the past we've relied on
>>> charity,
>>> and Amateur Radio Operators alone can not fund a launch, what you 
>>> haven't
>>> heard are any solutions for launching any HEOs.  It seems that the DL
>>> folks
>>> haven't lost that as a focus, they acknowledge that as expensive as it 
>>> is
>>> to
>>> launch an HEO, it is still doable. 3 - 4M Euros $4 - 5M at least they
>>> gave
>>> us a tangible figure we can work with.  This amount may be a reach for
>>> AMSAT-NA alone, but given that we finally understand what it would take
>>> to
>>> make a HEO Launch reality, then why wouldn't we shift ALL funding toward
>>> that effort?    Following the PE3 launch, if  any surplus remains, the
>>> surplus could be transferred to the next HEO opportunity (Eagle).  If no
>>> surplus remains then at least we would have one working HEO deployed.
>>>
>>> Additionally, at least we know the PE3 platform is well vetted, and 
>>> would
>>> have the lowest risk.  Rather than spending time and resources on a new,
>>> untested platform why wouldn't we just facilitate PE3 FIRST?
>>>
>>> Ok, I'll speech for myself here, but the GEO ride-share simply isn't an
>>> opportunity that will interest the HEO crowd.  Launching an appliance to
>>> serve the disaster response community and entry level satellite users
>>> won't
>>> do a thing to satisfy the need for a HEO.  I don't care if it's free,
>>> like
>>> AO51, I would probably get on it, make a couple contacts say "that's
>>> nice"
>>> and be done with it.  Please understand, I'm not saying to abandon GEO 
>>> as
>>> a
>>> viable option, just don't spend a cent on it until we launch an HEO.
>>>
>>> What we need is a satellite that enables the real sprit and intent of 
>>> the
>>> Amateur Radio Service, to push the envelop of the technology, allow for
>>> experimentation, consider all of the alternative antenna solutions that
>>> our
>>> resourceful community developed to receive the 2.4Gig Down Link. No
>>> rotator
>>> required, different feed systems, a fairly modest resource outlay to get
>>> on
>>> the air.  I did it with a totally home brewed system in a restricted
>>> neighborhood back yard. Had a blast and learned allot.
>>>
>>> ----- Original Message ----- 
>>> From: "John B. Stephensen" <kd6ozh@comcast.net>
>>> To: "Luc Leblanc" <lucleblanc6@videotron.ca>; <eu-amsat@yahoogroups.com>
>>> Cc: <amsat-bb@amsat.org>
>>> Sent: Friday, August 08, 2008 3:14 PM
>>> Subject: [amsat-bb] Re: [eu-amsat] AMSAT UK P3E Lecture Available
>>>
>>>
>>>> I've been hearing these two statments from AMSAT-NA officals for at
>>>> least
>>>> 2
>>>> years -- in person and on this BB.
>>>>
>>>> 73,
>>>>
>>>> John
>>>> KD6OZH
>>>>
>>>> ----- Original Message ----- 
>>>> From: "Luc Leblanc" <lucleblanc6@videotron.ca>
>>>>>
>>>>> Very nice presentations. One attract my attention was made by Peter
>>>>> Guelzow DB2OS one one of his slide we can read:
>>>>>
>>>>> ATTRACTIVENESS OF AMATEUR RADIO HAS DROPPED SIGNIFICANTLY
>>>>>
>>>>> FUNDING A SATELLITE FROM AMATEUR RESSOURCES ALONE NEVER WORKED BEFORE
>>>>> AND
>>>>> WILL NOT WORK NOW.
>>>>>
>>>>> I don't how to explain how all the wisdom and reality knowledge seems
>>>>> to
>>>>> be concentrated in Europe when speaking about amateur satellite?
>>>>
>>>> _______________________________________________
>>>> Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the 
>>>> author.
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>>>
>>> _______________________________________________
>>> 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
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>>
> 

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