[amsat-bb] Re: inquiry about homebrew az-el systems

[Hector, CO6CBF]

Hello Samudra

Two years ago, I constructed a rotating system using as main part a blood
pump’s motor reducer from a discontinued dialysis machine. The circuit to
give feedback to the ground station was based on operational comparators and
sensors were 360 degrees potentiometers. It was my first rotator! Even
though it was very elementary and primitive, it performed perfectly and got
me into satellites. All the parts required were recycled from discontinued
equipments.

This rotating system is still working. I have improved the feedback and
control stages but mechanical parts are as before.

In a separate email I have sent to you an .odbc file with my feedback
circuit design ready to simulate on Proteus.  

73!

Hector, CO6CBF
EL92sd 


-----Mensaje original-----
De: amsat-bb-bounces at amsat.org [mailto:amsat-bb-bounces at amsat.org] En nombre
de Samudra Haque
Enviado el: sábado, 23 de febrero de 2013 22:19
Para: Lizeth Norman
CC: Amsat-bb
Asunto: [amsat-bb] Re: inquiry about homebrew az-el systems

I hope it is evident, I am not focusing on the
controller/microcontroller/computer interface/az-el controller/etc. The
real issue is how cheaply can an antenna be mounted on a kingpost somewhere
on a surface, with a view towards the sky, and how conveniently can that
mount be motorized, with a sensor to give feedback to the ground station.
electronics, seem to be, (apologises to EE friends) a dime a dozen, cheaper
if made in hundreds, but the key drawback of any design is the mechanical
and electromechanical (can we use, mechatronics) system that serves as the
actuators. I am not referring to a hand held antenna assembly, but rather
something that we can all use in cold/hot weather and that can be put
together by one / two persons on an average post.

Comments welcome, I think the future holds bright for amsats and edu based
cubesats.


-samudra


On Sat, Feb 23, 2013 at 9:50 PM, Lizeth Norman
<normanlizeth at gmail.com>wrote:

> Gus and the group:
> Lots of birds going up in the next year. Success rate not 100% as it's
> rocket science oftentimes on a budget. Hopefully we'll get a few out
> of it.
> The Arduino IDE install supports PPM. The nice thing about that
> platform is that configuration is doable for just about all forms of
> hardware that you might drive with it and scaling can be done in
> software for the various different bits of kit.
>
> I am sure that with the appropriate development environment and having
> the hardware on hand IN a well equipped lab, it should be a weekend
> project to get running.
>
> The hard bit in my opinion is how to mount the antennas to the az/el
> clockwork. Will require a little woodwork/metalwork to finish.
>
> Everyone who does this will have a problem with some phase of it.
> Needs to be simple and repeatable.
>
> Norm n3ykf
> _______________________________________________
> Sent via AMSAT-BB at amsat.org. 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 at amsat.org. 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