Communication with guiding stops

Posting to several different groups so please excuse me if you’ve read this elsewhere already.

Programs involved: PHD, SGP and iOptron CEM60 standard, ASI 120mm

Been having issues the last several nights and not sure where the root cause is. In short, at some point during an imaging session PHD will stop communicating with my mount. As the guiding stops and the RA/DEC differential increases, SGP stops imaging and if the guider doesn’t settle will cancel the sequence.

I thought the error involved my mount as I was utilizing the built-in USB hubs. So Fri night I used an external USB hub. But the issues showed again. That lead to me thinking it was my RS232 to USB adapter so I used another one on the external hub. Obvioulsy that failed me as well.

My thinking remains towards the mount but I’m wondering if it was the RS232 cable that came with the mount that is the issue. But I’ll have to get another one from them and before spending money wanted verification.

To the best of my knowledge, the errors occurred around the following times (based on when my last images were captured):

October 16, 1:21AM
October 17, 1:36AM (questionable as this may have been the scheduled end of one sequence but for sure 3:44AM; was scheduled to run to 6AM).
October 18, 1:33AM (same as above but occured again at 3:43AM)
October 19, 12:11PM (no images after; SGP aborted as guiding would not settle BUT it did park the scope).

Particularly this morning’s occurence is strange. This makes me wonder if it’s actually in the camera…

The setup has my DSLR and ASI running to the CEM60 hub. The output from the hub runs to the external hub which also receives the RS232. Then the external hub pushes to my laptop. This is all USB 2.0 over a 30’ cable,no amplifier.

Before anyone assumes it’s the USB extension cable, I’ve never had these issues before. Of course I also recognizes that means very little.

Log files uploaded to DropBox: https://www.dropbox.com/sh/na2iqmnlv3rwfvv/AABq25gfUccQ4eeuQaYge0LTa?dl=0

It could be you’re exceeding the capacity of the hub. I know the ASIs are very sensitive to bandwidth. I remember when I started, I tried connecting all of my equipment through a hub and using only one repeater cable. I had issues. As soon as I went to a dedicated cable for either my main camera or my guider… problems went away. I’ve been doing that ever since.

Also, USB cables do go bad. You might find my comments on TXTimeout errors with my STF8300 on here (they might be in the beta threads…). As soon as I replaced the USB cable, they went away. The cables do go bad after they’ve been outside for months.

Hope that helps :smile: