USB to ST4 guider interface...for the hobbyist

[kinetic (Steve)]

Just found this posted on another forum:

http://home.comcast.net/~lynol1000/g.../guide_out.htm

Steve

[Bucky1379]

Hi All

I had a look at this and it seemed like a good value product and after some investigation I have ended up buying one although I haven't received it yet so can't give a report

I can report though that the guy producing them (his name is Gene) is extremely helpful which I need as I am just starting in the autoguiding game and really still have little idea how all the hardware and software bits work together.

His reply to my query yesterday helped me understand things a lot more and I thought I'd share it in case others find it useful.

I understand the dilema with all the pieces of the puzzle.
> To get something working from a guiding standpoint,
> assuming the guide camera does not have a native ST4 output
> not needing help (e.g. the Orion Solitare), you would be
> looking at:
>
> PHD->ASCOM->USB->ST4->Mount
>
> Where PHD is fairly simple on the surface but offers quite
> a bit of tweaking if desired to tune it to your mount. It
> can talk to the 'camera', read the images off of it, keep
> track of star location in the image and given a star you
> choose will send commands to the scope to keep that star
> centered. Now PHD natively supports quite a few things
> camera and guide output wise but for things not natively
> supported it relies on ASCOM to abstract the view of the
> hardware. Note that PHD for the PC talks to the USB-ST4 via
> ASCOM but on MAC it talks to the unit directly.
>
> ASCOM is a set of software platform interfaces and
> utilities that provide a common interface spec so the
> program using it (PHD in this case) does not need to know
> about the details of the actual hardware. It is all
> abstracted by the ASCOM 'drivers' which talk to the hardware
> itself.
>
> For guiding, PHD makes use of 2 abstractions in the ASCOM
> driver
>
> 'Move this direction for this long' and 'are you still
> moving'.
> These are named 'pulseguide' and 'isPulseGuiding'
>
> Gene
>
One final note for now. I bought the nore expensive optical relay version in the kit version (I have built electronic projects all of my life) and the total price including shipping was a bit overAU$61 which seems pretty cheap to me.
The fully built and tested unit is about US$18 more but in addition includes both of the required USB and RJ-11 cables.

Regards

Steve M

[AdrianF (Adrian)]

Originally Posted by kinetic

Just found this posted on another forum:

http://home.comcast.net/~lynol1000/g.../guide_out.htm

Steve

Thanks for posting this link. I have just made equiries to buy one.

Adrian

[mldee (Mike)]

Originally Posted by AdrianF

Thanks for posting this link. I have just made equiries to buy one.

Adrian

I bought one from Gene a few months ago to use with my EQ6, unfortunately I have been too busy with other things such as EQMOD to get PHD up and running to test it. I believe I got the optocoupled version as well.

The build quality is good and Gene keeps following up to see If I have had success, to which at this stage I have to keep replying 'no' as I haven't turned it on yet

One question he did have that I have not been able to answer is the type of electrical interface on the EQ6, ie, does it have pull up resistors for the signal or not? If someone could supply him (and me) that info, he would probably appreciate it.

[AdrianF (Adrian)]

Originally Posted by mldee

I bought one from Gene a few months ago to use with my EQ6, unfortunately I have been too busy with other things such as EQMOD to get PHD up and running to test it. I believe I got the optocoupled version as well.

The build quality is good and Gene keeps following up to see If I have had success, to which at this stage I have to keep replying 'no' as I haven't turned it on yet

One question he did have that I have not been able to answer is the type of electrical interface on the EQ6, ie, does it have pull up resistors for the signal or not? If someone could supply him (and me) that info, he would probably appreciate it.

Had a reply from Gene and he said that the only one he sold over here he hadn't any feedback about so he is assuming it works. I will be paying for one later tonight. Which version did you get with or without the FETs?

Adrian

[mldee (Mike)]

Originally Posted by AdrianF

Had a reply from Gene and he said that the only one he sold over here he hadn't any feedback about so he is assuming it works. I will be paying for one later tonight. Which version did you get with or without the FETs?

Adrian

I bought the GUIDE_OUT_V1_OC_1 model, which has open collector output. As mentioned, I haven't yet connected it to the EQ6 guide port, but in an earlier correspondence with Gene he said there appears to be 4 pullup resistors directly next to the guideport, so we went with the Meade-compatible OC configuration.

I also sent off a quick email to Gene this morning, advising him of the status of my unit.

Hope that helps.

[AdrianF (Adrian)]

Paid for the interface last week it should arrive sometime this week.

I have just picked my USB to ST4 guider interface from the PO. On initial inspection its well built and comes complete with the cables to connect to the Laptop and the Goto. Wont have time to test before the weekend as I have to run night classes for the rest of the week and I also have taken delivery of a Meade DSI Pro camera and I am itching to have a play with it as well. Arrrggghh too many toys not enough time.

Adrian