Ok, but why should I add an extra piece of hardware in the chain that can be removed without any loss of functionality to ekos? Or in other words, in the worst case the hand controller introduces another error source, in the best case it does ... nothing, sits there on your tripod and you can commemorate about the vendor and its solidness

Yes, but I found with the EQ mount I was using, that when I tried it with the hand controller attached using the Synscan driver, it mostly worked, but had less functionality and a time zone problem. And I found that when I tried it with the hand controller attached using the EQMod driver, it did not have a time problem, and of course could use the more advanced functions of the eqmod driver, but frequently dropped the connection and when it did so sometimes caused scary results when the mount slewed to the horizon. When I did it with the interface cable instead of the hand controller, everything worked, it was reliable, and had no issues that I could find.

I'm not against hand controllers, on my Gemini mount, which is what I mostly use for astrophotography, I always leave it attached. But it seems to me that with the EQ mount, this seems to work the best based on my experiments with it last summer. As for the other methods I tested: I don't think the direct PC connection through the Synscan controller is meant to be used with EQMod. The Synscan driver method was reliable, but it did have less functionality. So for this mount, I would probably suggest the cable instead.

I just lost my longer answer so the sort answer is that if you remove the HC you have to replace it with some motor driver electronics. I’d rather keep the manufactures stuff.

No you just need a cable, no drive electronics.

Once I got the cable, I safely packed away the hand controller in a box and put it on a shelf as a backup if my cable were to ever go bad. I did use it before the cable arrived, so I know I can use the synscan interface as well, but there is nothing to be scared of with replacing it with a good quality cable. In complex setups, one less piece of electronics and cable connections is not a bad thing.

Yes, you need this "EQDIRECT" electronics box inline with the mount - part of the "cable" people speak of. You have to make it yourself or buy custom - I forget where.

eq-mod.sourceforge.net/introindex.html

See my post above. www.indilib.org/forum/ekos/2820-eqmod-alignment.html#20981

I use a FTDI USB-RS232 converter on a RJ45 plug, as depicted at eq-mod.sourceforge.net/eqdirect2.htm. That is all that is needed.

The only thing I would improve on that hardware part is the slack in the mount's poor RJ45 plug, which was causing disconnections while the mount was rotating before I had that better secured.

This, and the voltage applied to the mount. Currently I have the same supply on both the dew heater and the mount, and this is a bad idea looking at the stability of the voltage. Sometimes the mount gets as low as 11V for a short period of time.

-Eric

I re-read a few things and yes, EQMOD says they can't guarantee reliable operation with the HC because its undocumented. However, it is documented (in my synscan manual). I'm not sure why they say that and makes me wonder to what interface spec they are working. And I wonder who wrote the INDI EQMOD mount driver and who's interface they are working to.

Edit: There is also a INDI synscan driver but I was advised to use the eqmod even though working through the HC.

I re-read a few things and yes, EQMOD says they can't guarantee reliable operation with the HC because its undocumented. However, it is documented (in my synscan manual). I'm not sure why they say that and makes me wonder to what interface spec they are working. And I wonder who wrote the INDI EQMOD mount driver and who's interface they are working to.

Yes, if I remember correctly, this item you are referring to: "EQMOD says they can't guarantee reliable operation with the HC because its undocumented." is when you connect with the PC-Direct setting on the Synscan hand controller, and this is everything that the Manual has to say about that:

"Currently, the PC direct mode is mainly used to update the motor controller’s firmware."

See page 19:
www.telescope.com/assets/product_files/i...ions/29526_03-14.pdf

In my experiments the PC-direct mode did in fact work, but it dropped the connection after a certain amount of time went by

I guess if you want to call voltage shifting TTL an electronics box, you would be correct. It is more than just a simple pass-through. One such provider that I have used with great luck is Shoestring Astronomy: www.store.shoestringastronomy.com/index.htm - there are others, just a happy customer. It is still simpler than a full hand controller with its extra connections.