After many years of use, I decided to "modernize" this scope.
OnStep (v4.24 running on MEGA2560 + ESP8266 + HC06) h/w is installed and working ok, functionality is very similar to Mel Bartels' software.
However, I had mechanical issue - vertical shaft (ø25mm) is still not stiff enough so the dob frame swings significantly which is quite annoying when windy and when un-intentionally touching the scope while observing.
I tried to use large lazy Susan (ø440 mm, purchased on ebay for that purpose couple of years ago), I tried it over the weekend and the improvement was dramatic, but I am also trying to find and implement the solution with lower resistance.
Small rubber wheels (3~4 riding on (rusty) ring welded on the tripod - I will have to flatten it and polish with angle grinder to make it aligned with vertical shaft), or ball bearings with rubber tubing is coming to mind.. I will try to put together something, but just in case there is some off-the-shelf solution.. I would try that first.
Does anybody knows about something suitable? maybe something like
this?