homebrew lx200 compatible autoguider

[bugle]

The auto guiding preps have progressed well.

Tonight have prototyped an lx200 command compatible autoguider project. Using an attiny2313, relays (what i had available, might upgrade to optocoupled transistors) to switch eq3-2 hand controller switches shoestring style.

LX200 commands implemented are:

:Mn# slew north

:Me# slew east

:Ms# slew south

:Mw# slew west

:Qn# stop north

:Qe# stop east

:Qs# stop south

:Qw# stop west

:Q# stop all

Focuser commands to follow...

If anyone is interested in a write up, code or possibly programmed uCs let me know... I may do a layout and etch some boards also... Other upgrade would be swap the MAX232 for an FTDI and power from usb, does anybody know of a through hold usb/serial ic? One of the FTDI leads with the chip moulded into the usb plug is also an option but at ~£15 pushes the costs up...

[JamesF]

Sounds very interesting. Please do post more details.

James

[bugle]

_{I am working on a write up of this guider, other things just getting in the way... As an update, I have swapped the relays for a Darlington array ic and done some testing connected to the mount (eq3-2). Results are promising, I have also connected to the guider using wxastrocapture and it responds to the guide commands.}

_{It was getting native support from wxastrocapture that was the main reason for building the guider, this will enable me to guide from linux}

_{I did some kicad work and have board artwork ready to produce a test board...}

[JamesF]

Life always seems to get in the way I'm pleased to see anything that reduces my dependence on windows though. Windows and I just don't get along.

James

[skybadger]

Have you thought about having a pic or arduino doing the image prcessing job and doing away with the pc altogether ?

sort of like the autoguider you see on the adverts but pluggable into most standard USB webcams rather than providing its own.

I have been thinking about this and I don't care if the update rate is low - say once every 1 to 4 secs as long as it can read an image, identify a star and track it , you only need your pc then to test the usb interface and as a debug uart..

In terms of do-ability - the Microchip libraries support composite USB devices on an 18F or 24 F device,

Operating at 32MHz need to read a 1/4 Mbyte image (2 Mbit ) into local memory, load it, find teh peak signals , discriminate and track.

Anyone done anything like this ?

Mike