TR707 HKA 8-kit and Cymbals mod installation

Installation of the HKA expansion boards (8-kit ROM and Cymbals) for the Roland TR707. These explanations add 7 more kits to your TR707 (also available for TR727). We install all HKA mods, please write us to gil.vintageanalog@gmail.com for the available options for your drum machine, or visit our Facebook page: https://www.facebook.com/electricianformus... Looking back at this video, there was an error installing the orange wire going to pin #4 of IC6. It has been wrongly soldered to pin #4 of IC16 (minute 54:00) instead of pin #4 of IC6 (Midi Optocoupler) which is located near the Midi ports. The wire enables preset change via Midi.