So I am now the proud owner of a 9 inch Ed Byers gear set as described in https://www.cloudyni...ded/?p=10725545 and have started building a mount that is hopefully worthy of the gear. https://www.cloudyni...ild/?p=10900867
This came with the "standard" Hurst 3002-025 1/2 rpm synchronous motor. I've also managed to find a geared stepping motor Hurst 3008-003 (0.2 degree steps and 75:1 gear reduction). (Note, Hurst sells these motors new but they are not cheap but occasionally they turn up on the surplus market.) This should be a drop in replacement. I believe that Ed used the 3008-002 (0.1 degree steps and 150:1 gear reduction for the stepping option for this model but have not confirmed this.
My goal for the mount is to use it by manually slewing the telescope by hand taking advantage of the slip clutches on polar and declination axis. Supply fine adjustments to allow guiding and fast enough slewing within a frame for final positioning.
1) Is there an available replacement for the spur gear circled in red? I would like to try the two motors without having to pull the gear when swapping motors. Was this gear standard or custom cut by Ed?
2) For the Hurst 3002-025 1/2 rpm synchronous motor, how large a range of speeds can be generated by varying the voltage frequency. Clearly the range needed for tracking is easily achieved, but probably not useful for the in-frame slewing.