DIY 5x MIDI Thru / Repeater Circuit

Here is a MIDI standard-compliant 5 x MIDI Thru Circuit. Each MIDI Thru port generates an exact replica of the MIDI signal on the MIDI In port.

Parts List:

  • C1 – C3: 0.1uF Ceramic Chip Capacitor
  • C4: 47uF Electrolytic Capacitor
  • D1: 1N4148 Small Signal Diode
  • IC1: 7805 Voltage Regulator
  • IC2: 6N136 Opto-Isolator
  • IC3: 7414 or 7404 Hex Inverter
  • R1, R3-R12: 220Ω Resistor, 1/8-watt or 1/4-watt
  • R2: 10kΩ Resistor, 1/8-watt or 1/4-watt


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