1. Some other designs use a variable supply to calibrate the rotator position - what does the LVB do ? 2. Does the LVB tracker get a command, move the antenna around, and shut out any other commands, untill it gets the first command sorted ? 3. What does the LVB tracker show on the screen ? 4. What protocols does the LVB tracker work with ? 5. I heard mention that the LVB does a few samples of the A/D to make sure it has a valid result from the pot's 6. The cct diagram shows two diodes, connected to each az and el a/d input, what do they do ?
---------------------------------------------------------------------------- Andrew Rich VK4TEC vk4tec@people.net.au http://www.tech-software.net
Hi Rich,
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 location. 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.
73 Kevin WA6FWF
----- Original Message ----- From: "Andrew Rich" vk4tec@people.net.au To: "Amsat-Bb@Amsat. Org" amsat-bb@amsat.org Sent: Tuesday, January 08, 2008 2:14 AM Subject: [amsat-bb] LVB tracker questions
- Some other designs use a variable supply to calibrate the rotator
position - what does the LVB do ? 2. Does the LVB tracker get a command, move the antenna around, and shut out any other commands, untill it gets the first command sorted ? 3. What does the LVB tracker show on the screen ? 4. What protocols does the LVB tracker work with ? 5. I heard mention that the LVB does a few samples of the A/D to make sure it has a valid result from the pot's 6. The cct diagram shows two diodes, connected to each az and el a/d input, what do they do ?
Andrew Rich VK4TEC vk4tec@people.net.au http://www.tech-software.net
Sent via AMSAT-BB@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
Hi Kevin and Andrew
- the LVB does its calibration in software, no variable supplies.
- it keeps accepting commands and acting on them.
- on the right side is the desired location, left side is the actual
location.
- 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 GS-232A works.
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
On Jan 9, 2008 6:45 PM, Howard Long howard@howardlong.com wrote:
Hi Kevin and Andrew
- the LVB does its calibration in software, no variable supplies.
- it keeps accepting commands and acting on them.
- on the right side is the desired location, left side is the actual
location.
- 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 GS-232A works.
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
This is a wonderful addition to the stable of AMSAT-related project. As I've been toying around with designing a track-box for Tony AA2TX's iRotor interface, I've learned quite a bit by reading the articles in the Journal relating to the LVB Tracker.
You mention GS-232A protocol and Easycomm I. I have my code parsing the GS-232A, which is easier because the parsing can be done by character position. But I was hoping to use serial-line rotor command protocol that included the name of the satellite being tracked so that that info could also be displayed. Does anyone know of such a beast, especially if it is supported by SatPC32? I went through that program's manual but had no joy.
73, Bruce VE9QRP
participants (4)
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Andrew Rich -
Bruce Robertson -
Howard Long -
wa6fwf