Having bought a new focuser (Baader Diamond Steeltrack) with a knob for a drive belt fitted; I had a go at building my own electronic focuser drive. I based it upon TekkyDave's ArduinoAscomFocuser2 project and driver:-
https://sourceforge.net/projects/arduinoascomfocuser/
His project seemed to work remarkably well and come together quite easily (I bread boarded it and ran the original stepper under Ascom in 30 mins). Because I wanted to change the project to suit a Nema 11 stepper etc it took me a good deal longer to get the final thing working. The worst bit was the mechanics (my painting was pretty bad too).
(https://c1.staticflickr.com/5/4447/36739633293_0a4d503ce2.jpg)
(flickr page (https://www.flickr.com/photos/151435098@N02/36739633293/in/dateposted-public/))
The jar of coins weighs 1.9kg. I'm testing it here for accuracy, load, repeatability /missing steps.
A nice feature of Dave's code is the temperature sensor using the Dallas DS18B20, which reports the temperature back via Ascom. The final thing weighs around 100gm and draws less than 0.5A when focussing, less than 0.2A when not in use.
(https://c1.staticflickr.com/5/4488/37379115912_48f27779f5_z.jpg)
The back view here (back removed) shows the stepper and Arduino Nano in place (12V and temp lead disconnected). I squashed it into a 50X50mm diecast box, but the stepper was a bit big for it. The Baader focuser had a mini-dovetail track already on it to attach an electronic focuser.
Anyone happy tinkering with Arduinos might like this project.
Well done Noel. I have yet to own an electronic focuser. I am sure the guys able to do this sort of thing will be very interested.
Carole
Very nice.
It's a very worthwhile project. Well done!
Mark
P.S. It was good to meet you at Wednesday's meeting - now I can put a face to your name :)
When I bought Mick Welham`s Meade, he had converted it with an electric focusser ... it works very well.