RE: [amsat-bb] Simplified Computer Rotor Control?

["Robert Bruninga" <bruninga@xxxxxxxx>]

>i was going to use a geared motor and count the 
>number of times of rotation of the shaft
>...15 turns = 3 deg change for example

APRSdos drivers for the simple 24v AC TV
rotators simply uses TIME.  They rotate at
1 RPM so 1 sec equals 6 degrees.  THus you
dont need any feedback pots or anything.
Just put a opto-isolator between bit one
of your parallel port and the CCW switch
and bit 2 and the Clockwise button and APRStk
does the rest.    Including re-sync.  It runs
for years and is always aligned (within 10 deg).
Not good for high performance AZ/EL OSCAR
arrays and AO-40 , but perfect for ALL LEO's

See http://www.ew.usna.edu/~bruninga/rotator1.html

I sure wish all Satellite Software implemented this
simple 2 bit, no-pots interface to the cheap $65
rotators...

de Wb4APR, Bob

-----Original Message-----
From: owner-AMSAT-BB@AMSAT.Org [mailto:owner-AMSAT-BB@AMSAT.Org]On 
Behalf Of Anthony Monteiro
Sent: Friday, 26 August 2005 1:51 AM
To: hasan schiers; amsat-bb@AMSAT.Org 
Subject: Re: [amsat-bb] Simplified Computer Rotor Control?


Hi Hasan,

I haven't had a chance to try this yet but I think the
simplest and cheapest way to do it is to use a digital
pot connected to a PC parallel port. You probably also want
a switch between the rotor controller pot and the digital
pot to select manual or computer control.

With this approach, you don't need any micro-controller, no
A/D or D/A converters, no power supply etc. All the software
is simple PC stuff - no special compilers etc.

73,
Tony AA2TX

---


At 07:02 AM 8/25/2005 -0500, hasan schiers wrote:

>I have  G-800SA Yaesu Azimuth and G-550 Yaesu Elevation rotors.
>
>I have no interest in spending a fortune on a 5500 and its (non-supplied)
>serial interface.
>
>Could someone point me to articles on the Web or commercial sites that show
>inexpensive interfaces that I might be able to use with the above rotors.
I'm
>assuming that one could tap off the pot voltages at the rotor control heads
>and feed them to an interface. This should not be all that difficult to do,
>and I assume has been offered as a less expensive alternative to the
internal
>interfaces.
>
>If someone has keywords that will provide useful url's I'd be happy to
google
>them. I just thought I'd check here first if someone has already done the
>sifting.
>
>73,
>
>...hasan, N0AN
>----
>Sent via amsat-bb@amsat.org. Opinions expressed are those of the author.
>Not an AMSAT member? Join now to support the amateur satellite program!
>To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org 
>
>
>
>--
>No virus found in this incoming message.
>Checked by AVG Anti-Virus.
>Version: 7.0.344 / Virus Database: 267.10.15/81 - Release Date: 8/24/2005
----
Sent via amsat-bb@amsat.org. Opinions expressed are those of the author.
Not an AMSAT member? Join now to support the amateur satellite program!
To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org 
----
Sent via amsat-bb@amsat.org. Opinions expressed are those of the author.
Not an AMSAT member? Join now to support the amateur satellite program!
To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org
----
Sent via amsat-bb@amsat.org. Opinions expressed are those of the author.
Not an AMSAT member? Join now to support the amateur satellite program!
To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org