Roland MIDI Channel Filter/Converter MPU-103

Roland MIDI Channel Filter/Converter MPU-103     No serial number   Condition:  Excellent (Studio use).

•   MIDI In, Out and Thru back panel connectors
• Rotary knob to select MIDI channel 1-16
• If Converter ON/Off switch is off, only selected channel messages appear at MIDI out
• Rotary knob to select converted MIDI channel 1-16
• If Key Event only switch is off, only selected and converted(channel) MIDI messages appear at MIDI out
• If Key Event only switch is on, then only ‘Key’ (Note On/Off) messages appear at MIDI out, either on the selected channel, or on the selected and converted channel
• Convenient “circuit diagram” on the lid
• Standard Roland (Boss) 9v DC power supply (pin is negative).  PSB-1U or similar.