[amsat-bb] Space Center Abandoned Dish Rehabilitation - Outreach #1
Zach Leffke
zleffke at vt.edu
Thu Aug 15 04:49:05 UTC 2019
I don't mind throwing out a few ideas, even if its beyond
salvaging...its fun to think of ideas and potential use cases for these
kinds of things.......(hobbies are for fun right?)......
For those interested, looks like this is the one: 34.711786, -86.653985
(copy/paste into google maps). Not this one: 34.711070, -86.654875 (had
me distracted for a bit...that also maybe looks like its no longer in
use with better southerly views?)
Idea 1: GEO TT&C and/or Gateway?
If we get a GEO bird, ~20ft/6m aperture could be useful as a (maybe
backup?) command station for the 5/10 GHz strategy. Or alternatively a
'gateway' of sorts for user traffic (again maybe backup)?
For this specific antenna, if we can get a view of the GEO belt over the
buildings to the south, could be feasible. I agree with Bob that the
blockage looks pretty significant to the south, but the 3D google street
view make it look 'not so bad' for GEO maybe (thats a pretty big
maybe....perspectives could be skewed in that view though, and its hard
to concentrate when looking at an SR-71 in front of you and the Saturn V
to the right).
For a GEO use case....would have to consider:
1. Can we see the GEO belt at all?
2. at 5 and 10 GHz we're talking sub 1 deg beamwidth. For a non
geostationary bird, that means peaking up. If the motor drives (if they
exist) can't keep up with a LEO bird, perhaps they could keep up with
the 'figure-8' of a slightly drifting geosynchronous bird with a bit of
inclination (few degrees of az/el over a sidereal day.....sort of like
furlongs per fortnight). If there are no motors at all, and we have a
geostationary bird, and we have a view of it, maybe it could be
're-parked' to point at the bird (even a drifting bird coming in and out
of the main beam could be useful/fun)....maybe that 'crank wheel' has
something to do with manual control?
3. Feed would have to be replaced (obviously).
4. As it looks like it was originally for VHF or UHF, might want to
confirm the mesh is usable at microwave freqs (not sure of the mesh size
from the pictures).
5. concerns about high power 5 GHz TX RF at a place heavy with general
public traffic? Concerns about proximity to Marshall Spaceflight Center
and potential 5 GHz Radars nearby (limiting our ability to TX, not
RX......I've heard of similar issues for ionospheric work and
restrictions in the area...but that was down at HF)? If so maybe a
downlink only station?
Idea 2: maybe the more important/valuable one?
Technical matters aside for a second.....having an active (even if
remotely controlled, and even if with degraded performance, restricted
field of view, etc.) antenna operated by Hams in the US Space and Rocket
Center can only be a good thing in terms of public outreach and raising
awareness for Amateur Radio in general (and maybe AMSAT/GNU Radio more
specifically), whether its being used for EME, Satellite, maybe balloon
tracking, or whatever? Our own 'live' Ham Radio exhibit, at a pretty
big NASA museum, with a lot of foot traffic......thats gotta be good for
'business' right?
Imagine you are 10 and are interested in Space. Your parents are taking
you to see rockets in Huntsville...you are walking around looking a lot
of 'not moving, but still really cool' things.......and out of the
corner of your eye, that 'HUGE' dish starts moving around (way bigger
than the one on your house that never moves.....super cool). So you run
over and start reading the plaque....and realize its being used for
Space Stuff RIGHT NOW!!!!.......and theres this thing called Amateur
Radio (plaque says so).........'Mom/Dad...whats Amateur Radio? can I do
Amateur Radio.....is this like the Ham thing uncle so and so is always
talking about........' BAM, the next Hiram Percy Maxim.........thats a
win right? That kid......first boot on Mars.....and it alllll started
when he took a trip with his parents and saw a dish moving
around......(OK, maybe a stretch.....but still).
Also..instead of plaque....maybe weather proof spectrum displays? Maybe
some kind of audio......Maybe something like the 'pulse of exploration'
from JPL DSN (more like a technical art exhibit, google it, pretty
cool)......and if not outside for that stuff.....maybe a small area
inside with a view out of the front windows of the dish?
So I guess what I'm saying is that getting a 5 or 6m dish and
refurbishing it in your back yard might not be impossible, and its
probably easier than dealing with the 'woes' of this particular dish,
and it would probably perform better for whatever the
application.......getting a 6m dish active for Hams at a pretty high
traffic NASA museum......for the community, that might be priceless (and
worth the 'woes' of this particular dish, something about beggars and
choosers.......).
-Zach, KJ4QLP
P.S. the site in NC that was mentioned in a previous post is called the
Pisgah Astronomical Research Institute, aka PARI.
--
Research Associate
Aerospace Systems Lab
Ted & Karyn Hume Center for National Security & Technology
Virginia Polytechnic Institute & State University
Work Phone: 540-231-4174
Cell Phone: 540-808-6305
On 8/14/19 11:45 PM, W3AB/GEO via AMSAT-BB wrote:
> Everyone, please chill.
>
> As I asked before, has it been "surplused"? Everything stripped from it. No one even knows what "model" it is and who made it. Plus what is on board. Speculation is really worthless compared to facts.
>
> Just like the rocket on display; anyone think it'll ever fly again?
>
> And, here is an example of another "opportunity" that fell apart. I shared this as well.
> https://en.m.wikipedia.org/wiki/Jamesburg_Earth_Station
>
> ___
> Sent from my two way wrist watch
> 73 de W3AB/GEO
>
> On Aug 14, 2019, 18:49, at 18:49, Robert Bruninga via AMSAT-BB <amsat-bb at amsat.org> wrote:
>> EME seems most practical...
>>
> >From the shadows, it looks like it is on the north side of the building
>> and has SERIOUS blockage to the east and west through south maybe as
>> high
>> as 40 degrees or more. Then trees block the North and NE. About the
>> only
>> sky it can see is NW?
>>
>> Since LEO's spend 70% of their time in view below about 22 degrees, My
>> guess is that this dish could only see about 10% of all possible pass
>> times?
>>
>> But EME is high most of the time. And easy to schedule around times of
>> high passes for a club station at a museum. Also would be a high
>> interest
>> item and things MOVE SLOWLY!
>>
>> If it is rusted frozen, then the EASY way out is to point it roughly
>> south
>> some how. And then wait for the moon to pass through its field of
>> view.
>> Hummh, lets say using the 2m feed the beamwidth is 5 degrees and the
>> moon
>> goes 180 degrees in 12 hours. Then its in view (3dB) maybe 20 minutes
>> at
>> a time?
>>
>> Then to improve the number of days, one could add another dipole above
>> and
>> below the existing one and then pick up additional passes without
>> having
>> to move the dish. Or easier, just nutate the feed up and down. Then
>> you
>> could get a moon pass every day.
>>
>> You could predict and post a schedule of when people could make
>> contacts.?
>>
>> Just playing with ideas...
>>
>> Zooming in with google earth in 3d you can stand ANYWHERE and almost
>> see
>> the same views as the excellent ones alrady posted. But walk around
>> and
>> fine tune them. Amazing...
>>
>> Bob, WB4APR
>>
>> -----Original Message-----
>> From: AMSAT-BB <amsat-bb-bounces at amsat.org> On Behalf Of John Kludt via
>> AMSAT-BB
>> Sent: Wednesday, August 14, 2019 9:25 PM
>> To: Michelle Thompson <mountain.michelle at gmail.com>
>> Cc: AMSAT BB <amsat-bb at amsat.org>
>> Subject: Re: [amsat-bb] Space Center Abandoned Dish Rehabilitation -
>> Outreach #1
>>
>> Michelle,
>>
>> So help me understand - what is the problem we are trying to solve?
>> Let's
>> play this out, we somehow get our hands on a surplus dish and we fix
>> it
>> up. I will skip over the part of the story that deals with annual
>> maintenance costs and ongoing operational costs every time we fire it
>> up
>> and use it. The question is, use it for what? A dish for the sake of
>> saying, "Heh, we own a dish" - who ever "we' is - just does not make
>> any
>> sense.
>>
>> I suppose we could use it as part of a network of stations on 2.4 MHz
>> for
>> HamTV but that works only if the dish is part of a greater US HamTV
>> network
>> that does not exist right now. And it only works if the Az/El system
>> turning the dish is a fast enough to keep up with a LEO such as the ISS
>> -
>> that is simple question of fact that we can discover. Other uses
>> that
>> would benefit the general amateur radio satellite community?
>>
>> While it is a cool idea at least to me it feels a bit like a solution
>> in
>> search of a problem. Not saying it is bad idea but I am saying so help
>> us
>> understand why we need a 20 foot dish owned by the amateur *satellite*
>> community at large. The other part of me that does EME sees lots of
>> uses
>> but that is very different game - see HB9Q. And before we get too far
>> down the road, I'd like to see not just acquisition and repair costs
>> but
>> ongoing maintenance and operations costs.
>>
>> Respectfully,
>>
>> John
>>
>>
>>
>>
>>
>> On Wed, Aug 14, 2019 at 5:12 PM Michelle Thompson via AMSAT-BB <
>> amsat-bb at amsat.org> wrote:
>>
>>> A group of GNU Radio community members has permission to evaluate a
>>> dish installation in Huntsville, AL near the Space Center. If you've
>>> ever been to the Space Center (where the Saturn V is suspended from
>>> the ceiling) then this dish is right outside the main entrance.
>> Anyone
>>> attending Symposium last year should recognize it!
>>>
>>> Here's a set of photos:
>>>
>>>
>>>
>> https://drive.google.com/drive/u/0/folders/1d_Oi3hrIi49JxmaoNuUA-pvUXO
>>> s7vSz1
>>>
>>> We're looking for technical information, identification of what you
>>> recognize in the photos, recommended next steps, and what to watch
>> out
>>> for, prioritize, or avoid. We already know we want to take the paint
>>> off all the ID plates and see what's under there.
>>>
>>> We want to see if we can get this working for *amateur radio
>> operators
>>> to access over the internet*, ideally with a GNU Radio flowgraph to
>>> control it from an SDR. Our priority is to make this work for amateur
>> satellite.
>>> This type of setup is similar to what GNU Radio Foundation is working
>>> on with the Allen Telescope Array. We have the go-ahead from the
>> Space
>>> Center curator to do this study and make recommendations.
>>>
>>> I have fully restored several basket-case British sports cars and
>> then
>>> successfully raced them. My other team members have restored things
>>> even more challenging. We are not dumb, naive, or easily deterred. We
>>> know this may turn out to be something that requires way more work
>>> than we can do in any time frame we can manage. Documenting that is
>>> still of great value, and that is why we are asking for your help.
>>> Right now, no one knows much of anything about it. This sort of
>>> installation, if available for amateur radio, is well worth the
>> effort.
>>> Some of the people involved have been driving past this installation
>>> for 20 years and want to see it back in service at whatever level we
>> can
>> achieve.
>>> It will be discussed at GNU Radio Conference, and everyone at the
>>> conference will have the opportunity to see it up close and in
>> person,
>>> since it's literally across the parking lot from the venue.
>>>
>>> Want to attend or find out more about GRCon?
>>> https://www.gnuradio.org/grcon/grcon19/
>>>
>>> If you know of someone off-list that might know details that will
>>> help, then please pass this along!
>>>
>>> -Michelle W5NYV + Corps of Operation Flashlight
>>> _______________________________________________
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>>> to all interested persons worldwide without requiring membership.
>>> Opinions expressed are solely those of the author, and do not reflect
>>> the official views of AMSAT-NA.
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>> program!
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>> _______________________________________________
>> Sent via AMSAT-BB at amsat.org. AMSAT-NA makes this open forum available
>> to
>> all interested persons worldwide without requiring membership. Opinions
>> expressed are solely those of the author, and do not reflect the
>> official
>> views of AMSAT-NA.
>> Not an AMSAT-NA member? Join now to support the amateur satellite
>> program!
>> Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
>> _______________________________________________
>> Sent via AMSAT-BB at amsat.org. AMSAT-NA makes this open forum available
>> to all interested persons worldwide without requiring membership.
>> Opinions expressed
>> are solely those of the author, and do not reflect the official views
>> of AMSAT-NA.
>> Not an AMSAT-NA member? Join now to support the amateur satellite
>> program!
>> Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
> _______________________________________________
> Sent via AMSAT-BB at amsat.org. AMSAT-NA makes this open forum available
> to all interested persons worldwide without requiring membership. Opinions expressed
> are solely those of the author, and do not reflect the official views of AMSAT-NA.
> Not an AMSAT-NA member? Join now to support the amateur satellite program!
> Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
--
Research Associate
Aerospace Systems Lab
Ted & Karyn Hume Center for National Security & Technology
Virginia Polytechnic Institute & State University
Work Phone: 540-231-4174
Cell Phone: 540-808-6305
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