4 replies to this topic

[afeld38]

I have been using Backyard eos with my set up,  I connect to my mount through PHD2 using an ST-4 cable.  It works fine but now I am trying to switch to NINA so that I can use plate solving to get to my targets.  Anybody know if NINA can connect to an AVX mount through an ST-4 cable attached to the guide camera?

[acrh2]

I have been using Backyard eos with my set up,  I connect to my mount through PHD2 using an ST-4 cable.  It works fine but now I am trying to switch to NINA so that I can use plate solving to get to my targets.  Anybody know if NINA can connect to an AVX mount through an ST-4 cable attached to the guide camera?

I think that the answer is no. You would have to connect your mount to your computer directly. I think there's a usb port on the hand controller. Or bypass the hand controller with an eqdirect cable that has an ftdi serial-to-usb chip. 

[TelescopeGreg]

I think that the answer is no. You would have to connect your mount to your computer directly. I think there's a usb port on the hand controller. Or bypass the hand controller with an eqdirect cable that has an ftdi serial-to-usb chip. 

The AVX "Pulse Guiding" computer connection port is the one on the hand controller's base.  Current NexStar models are USB; old units had a "classic" serial port requiring a special cable, and a serial to USB dongle if the computer doesn't provide a classic (DB9) serial port.  One cannot connect the mount directly to a computer for pulse guiding, as is done with the EQ6R and similar.  You have to use the hand controller; think of it as just a fat spot in the wire.

 

The mount does have an ST-4 guide port, which PHD2 can talk to via an appropriate guide camera.  Be sure you are using the correct interconnect cable.  The typical "phone jack" cables are not all wired the same.  Magic smoke can be involved.

[afeld38]

I may have figured it out.  Apparently the ST-4 cable has very limited data transfer ability, and therefore can not be used to interact with NinA.  I will have to go directly from the computer to the mount with a USB to mini USB cable hooked into the hand controller.

 

Thanks to all

[TelescopeGreg]

I may have figured it out.  Apparently the ST-4 cable has very limited data transfer ability, and therefore can not be used to interact with NinA.  I will have to go directly from the computer to the mount with a USB to mini USB cable hooked into the hand controller.

 

Thanks to all

Um, worse than that.  "Limited data transfer" is a gross overstatement.  ST-4 is just 4 parallel "bits", one each for left, right, up, and down (or, rather, the RA/Dec equivalents).  It's a one-direction computer-to-mount interface, effectively simulating the "human guider" (remember the old-time astro pictures?) pushing the direction buttons on a virtual keypad.  In days gone by, it was driven by a computer parallel port.

 

Pulse Guiding is a 2-way chat between the mount (or hand controller in this case) and the computer.  The computer can tell the mount where to go and what to do, and the mount can tell the computer where (it thinks) it is.  Through ASCOM or INDI, several clients (software applications) can have this chat with the mount, including NINA, PHD2, and others.

Edited by TelescopeGreg, 28 November 2021 - 07:00 PM.