Question Dec Dither Overshoot and Long Settle Times on M-Uno

Hi Rick,
Did you diagnose those issues yourself or did you return the Mount to Avalon? If the former, well done! It would be great if you could post some pics so others can see what to look for.

I'm in the USA so I thought I'd try working on the mount first. As I mentioned in earlier posts I first put a board in the saddle and used a dial indicator to monitor the movement as I pushed the hand controller buttons. With the cover off I could hear the motor and see the motor belt move when I pressed the buttons. If was repeatedly pressing the button to go in the same direction the dial indicator would move immediately. If reversing direction the motor would move but the dial indicator would lag by up to 13 seconds. When I took the DEC axis apart I found the issues I mentioned in a previous post. I was in contact with Avalon who asked for pictures.

Avalon sent some new belts and a replacement pulley. With all the new parts the PHD2 measured backlash is about 300 to 500msec. I still think there is a need for a software fix to help eliminate the very small remaining backlash. Even Astro Physics has a setting for backlash.

Avalon is very insistent these are zero backlash mounts, but I think with 4 belts, pulleys and many bearings between the motor and the telescope there will always be some backlash. What is normal? How should it be measured (PHD2) ? What value is a problem?

What values do others get on the PHD2 backlash test.