We kick off the New Year on the Synthchaser channel with troubleshooting and repair of this ARP Pro/DGX Mk I, which is the same as the ARP Pro Soloist with the exception of having pushbutton switches for voice selection instead of toggle switches. This Pro/DGX has no output at all, so together we troubleshoot and repair it, and in the process I explain how one of the least understood circuit boards in the synthesizer works.
