Stepper motors with belt drive reduction connected to the RA and DEC worm gears.
I used parts purchased from ebay.
Nema 17 0.9degree 4lead 2.4A 60oz-in Stepper Motor
12V 10/A Switching Power Supply Driver for LED Strip
GT2 Timing Pulley Aluminium 40 Tooth 2GT Bore 8mm Width 6mm
GT2 16 Tooth 5mm Bore Aluminum Timing Pulley
GT2 Timing Belt Annular Loop Rubber 6mm Width 2mm Pitch Close End 150-2GT
I built an AstroEQ drive electronics based on the MEGA Arduino. The expansion board mounted on top carries the driver chips, voltage regulator, diodes and LED’s in a project box with a clear top. The connections are just run straight out the box through holes rather than box mounted plug ins for simplicity.
Some of the parts needed:
Black Cased MEGA 2560 R3 Board ATmega2560-16A
Prototype PCB for Arduino Mega 2560 R3 Shield Board DIY & Breadboard
L7809 Voltage Regulator IC 9V 1.5A
DRV8825 Stepper Motor Driver 3D Printer RAMPS StepStick Module with heat sink
Waterproof Clear Cover Plastic Electronic Project Box Enclosure Case
1x40Pin Single Row Straight Male Copper Pin Header 4 PCB Arduino
The 50mm finder scope is a generic unit purchased on ebay with a helical focuser. The camera is a ZWO ZWO ASI 120 mm which works very well auto guiding with PHD2.
50mm CCD Image Guide Scope Finderscope w/ Bracket for Astronmical Telescope
These basic finder scopes work great! They are a lot less money on ebay…