If you are already using a computer in your observatory for other reasons, this provides a way for you to focus your telescope without fumbling around in the dark for the focuser handcontroller. It works best with 5V focus motors such as the newer style JMI Motofocus, but can also work with 9V or 12V motors. Motors requiring up to 100mA of current will work with the FCUSB. To date, the FCUSB has been tested with the JMI Motofocus, Moonlite DC motorized focusers, Orion AccuFocus, Meade 1209 and Televue Focusmate Driver.
The FCUSB also eliminates the need for a battery to run your focuser, since the motor is now powered directly from the USB port of your computer. Using the free FocusPal software, you can control the speed and direction of your motor with just mouse clicks! For further information, please read through the FCUSB User Manual Third-party software that supports the ASCOM Focuser standard will also work with the FCUSB using the FCUSB ASCOM driver. DC focus motors don’t provide absolute positioning repeatability like a stepper motor does. Please be aware that most third-party autofocusing software will not work with a DC motor controller.