Using the HBG3 "Standalone" with a Focus Motor

With the addition of a diode and a 12V power input jack, the HomeBrew Gen3 (HBG3) accessory can be used "standlone". That is, without a connection to a Celestron mount's AUX port. This is primarily useful for managing a Celestron Focus Motor (or HBG3 Focus Motor) on a non-Celestron mount.

Without an AUX connection to a Celestron mount, one has to arrange an alternative for 12V power input to the HBG3. Wire up an inline 12V DC jack (5.5/2.1mm, centre positive) to the +12V pad near the GPS pads and any available GND pad on the HBG3. Use a diode (1N007 or similar) inline between the jack and the +12V pad, to prevent frying things when eventually somebody does try and use it with an actual Celestron mount.

An AUX cable is still used, but only between the HBG3 and the Focus Motor accessory, providing both power and control of the motor. With this setup, no Celestron mount is needed. One just feeds +12V into that jack, and it powers both the HBG3 and the Focus Motor accessory. One can use a NunChuck to adjust the focus.

See here for Nunchuck information and usage instructions.

Standalone configuration for Focus Motor control

For remote/computer control of Focus, one can still use the Celestron Focuser Utility Program over USB to the HBG3, to control and manage the Focus Motor. Ditto for using Celestron PWI software (aka. CPWI) with either WiFi or USB, to manage just the Focus Motor without a Celestron mount.