[amsat-bb] Re: LVB tracker questions
howard at howardlong.com
Wed Jan 9 14:45:22 PST 2008
Hi Kevin and Andrew
> 1) the LVB does its calibration in software, no variable supplies.
> 2) it keeps accepting commands and acting on them.
> 3) on the right side is the desired location, left side is the actual
> 4) I know it works with the GS-232a protocol W135 035 W (az) (el)
> maybe someone else knows.
> 5) Howard has mentioned this before on the bb and I believe its in his
> write-up on the tracker that he does multiple samples and averages them
> to get a more stable reading.
> 6) I think the diodes you are referring to go to the plus voltage for
> the position pots and to ground, if those are the ones you are talking
> about then they are there to limit any spikes on the az or el position,
> any negative voltage gets shunted to ground, any positive voltage greater
> than the supply gets shunted there.
That about sums it up!
As well as the GS-232A protocol it also supports Easycomm I. It looks at the
command sentences and automatically knows from their structure what protocol
is in use. Smart eh? ;-)
The GS-232A seemed to be the most widely supported protocol at the time, and
I've not had any complaints yet that it should support anything else.
Note that there are some esoteric GS-232A scheduling commands that are not
supported. Also calibration is performed differently. The reason calibration
is done in software was so that I didn't need to have to keep adjusting the
G-5500 trimpots every time I changed the rotator controller interface.
As Kevin has already alluded to, the movement of the rotor is monitored
simultaneously as commands are accepted. All commands are acted upon
immediately whether or not the rotor is already moving. So you can override
a previous command immediately simply by sending another. This is how a real
Note that the LVB Tracker does not detect a stalled rotor by itself - this
is a job for your favourite tracking software.
73, Howard G6LVB
More information about the AMSAT-BB