Telescope drives for long exposure photos use variable speed drives using a reference star in a seperate sighting 'scope for targeting.... and have to deal with the earth's rotational degree every 4 minutes to track.
Your target is static , so a hunting algorithm ( up/down , left/right ) for best signal strength or BER might work.
Any help?
Allan
MorganS:
What is your ongoing problems now?
Actually, no much changes from the time I've started this thread. I still have no idea what kind of equipment (device) I need to connect receiver to Arduino.
allanhurst:
Any help?
Allan! Thanks for that, but best signal finding is completely another issue.... That maybe problem of my poor English that I am being misunderstood.
I will try to explain once more the process as I see it:
There is video https://www.youtube.com/watch?v=p3IWbRlhWBA&t=3s of the antenna which moves from West to East. And it is following the Clark belt where are all TV satellites are located, and if I stop antenna at the proper time then signal from separate satellite could be received. When motor is powered it moves antenna and also generates pulses. Let's say 1000 pulses from West to East (from the one end switch to another). So, position of the antenna in the middle oof the arc can be determined by the time it travels from one position to another or, the more precise way- when number of pulses is counted. For example, if we know that from end position to our chosen satellite there are 150 pulses than it is task of the positioner to count those pulses and cut the power of the motor exactly after 150 pulses.
OK I misunderstood. It seems the problem is getting a reference position on start-up.
You could run the motor in either direction until it stops with the limit switch.
Then reverse the motor and count pulses in the other direction to a pre-determined satellite position and stop the motor.. An arduino could easily do this.
Allan.
Would be much better if Arduino could always know the position of the dish. For example if dish is not at the end position but at Satellite "A" and I wish to turn antenna to satellite "B" which is only 50 pulses away, it would be much faster to go only 50 pulses instead of turning antenna to the end position and then start to count pulses to satellite "B".
An absolute encoder would do it.
Or calibrate with the end-stop once, then count pulses up or down to the present position, and store in eeprom before shutdown. The eeprom.update() function is useful to avoid unnecessary writes.
Then on start-up, read that value to know where you are. Only if out-of-sync do you need to recalibrate.
Allan
Hi! I've borrowed sketch from another project which can count the pulses generated by hall sensor. For experiments I have DC motor with magnet on it and Arduino Pro Mini plus LCD display. When motor is turning pulses are counted. If I change the polarity of the motor power it starts to turn opposite direction, but pulses on the display continue to increase. How that could be possible to tell arduino that if polarity of the power of the motor changed than pulsed should be extracted? I hope it is understandable what I am trying to explain.
If you are careful to fully stop the motor between reversing directions, then you could just look at your internal variable that knows you're driving forwards or backwards and use that to decide to increment or decrement.
Of course in the general case the motor may still be rolling forwards when you engage reverse so then you do need to actually measure direction with a second sensor.
In case of my project there will always be full stop of the motor and after some time revers or same direction rotation can occur. So, there will always be +/- to the motor = increase of the pulse count and -/+ should always decrease counting.
Way back when, I was data comm manager in Seattle. We had a satellite link to Hawaii via SanFrancisco. Twice a year the link was turned off for about 1/2 hour due to the satellite and the sun being in alignment.
Does your LNA have to be turned off similarly to keep the sun from damaging it?
Paul
Paul! You are speaking about sun-outage. This phenomenon happens twice per year (March and October) and lasts several days (depending of the dish size). During those periods signal levels are decreasing and in some cases full drop-out can happen. But physical damage to the LNB usually not happens. I like sun-outage periods, it is good time to do some experiments and also look whether your antenna is properly placed. However, sun-outage has nothing to do with arduino 
