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Re: "Space Scanner" - Automatic Satellite TV Tracking System

Several hams have played with these for various purposes.  These used to be sold at Allelectronics in Los Angeles where I bought mine.  The individual motors were sold at www.allelectronics.com but I don't see them in their current web site.  The complete actuator assembly is about the size and weight of a bowling ball and is designed to be used on mobile platforms like boats and RVs, so they see a lot more motion than simply changing from one sat to another.  If I remember correctly, the motors ran on 12V and had a 24V brake.  The motors can run on much less voltage if you want them to run slowly.
Tony, KC6QHP has used one for mounting his 10 GHz antenna, formerly a standard Ku band TV dish.  He had planned to control it via a homebrew controller, but I do not know if he completed the project.  Photo of the mounted antenna used in the 2002 Microwave contest is at http://www.ham-radio.com/sbms/02_testpics/02_test_qyr/qhp_1.jpg  This set-up simply had switches to actuate up/down and left/right.
More recently N6CA and others have been playing with these.  He has some notes at http://www.ham-radio.com/n6ca/microwave/trkr/trkr.html.  The motors should work for a small satellite array, but the control will require some tinkering.  I don't know if any sensing of motor position is included in the stock motor set-up, but I don't think so.  N6CA's notes show a potentiometer, but I think that is a modification.  I have been unable to get mine open due to some very stubborn screws.  The motors and gears look to be fairly strong with steel gears etc.  I wouldn't try to mount a big array on one, but I'm sure it could handle a small array for LEO V/U, U/S or L/S especially if BBQ dishes were used to minimize wind loading.
John, KJ6HZ
Hi Mike:

Mike, K4HN wrote:

> I've seen these at the Orlando hamfest the last two years. They are setup
> pick out the DISH and DirecTV type geosync sats.  You tell it which one
> it points the dish to it.  I looked at the manual in Orlando and couldn't
> see an easy way to make it track a non geosync sat.  It looked to me like
> its logic was set up to track the equatorial geosyncs only".

I read the info on the manufacturer's website.  Yes, it looks like it is
designed to only track the equatorial geosyncs only.  I do not expect to be
able to automatically track any non-equatorial geosync satellites.

I would like to determine if it is reasonable to modify the unit and use it
as an Az/El positioner for a DSS dish connected to a PC controlled antenna
rotor interface.  Since the motors are 12 VDC with 24 VDC brakes, this seems
very reasonable.

However, the motors and gear assemblies would experience a lot more use in
tracking a LEO or HEO satellite as opposed to occasionally changing position
to a different Geo-sync satellite.  I was hoping to find out if anyone had
tried to use one of these units and if the motors and gear assemblies are
heavy enough for Amateur satellite tracking.


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