I think you're right Rainer - not worth taking any risk by being too "creative". I'll use the GPUSB-AH from now on for guiding as it seems to work. That will free the RS232 port for the Gemini alone [Application on the laptop ] and I can use ASCOM POTH if I need to connect cartes du ciel or other planetarium utilities.
I read a few of your posts in the past and you mentioned you guide through the RS-232 on the Gemini. I do that too but the difference is that my laptop doesn't have a serial port, so I use a USB port then convert to serial with a cable.
The only thing I am a bit paranoid about is ground loop currents. Now I'm going to have a QHY8 in the circuit connected via USB in the circuit I'm a bit nervous, that's what prompted me to change my cables and the way I do the wiring. I heard and read in the past horrible things with SBIG STL11K having fused relays etc... because of similar voltage difference problems.
I'll post or PM a schematic of my setup with the mount/gemini and all my power sources when done so you can have a peek at it and let me know if you see any obvious flaw or potential problem.
Thanks for your help so far. Much appreciated.
Quote:
Originally Posted by rsbfoto
Hi Marc,
PIN 1 is not used. You got 5v because the PIN2 is the common or ground and PIN1 carries voltage for a different purpose which has not yet been specified.
PIN 3,4,5 and 6 are the guiding pins. Take a look into the Gemini Instruction manual located here
http://www.docgoerlich.de/manL3V11/GeminiUserManual.pdf page 92
There is one thing that the voltage of the old Gemini GoTo control box is a negative voltage and not a positive voltage like in the new Gemini GoTo box.
Pin 2 is the common and the pins 3,4,5 and 6 carry -5v when measured against common = PIN2
I do not know how the output of the QHY8 is but you should be carefull not to fry anything.
The best thing is to use the GPUSB-AH you have. |