M-261 MIDI Thru

TRS MIDI Thru Type A/B one-to-four

From the top down:
tip-ring or ring-tip switch for outputs 4&3
MIDI output jack 4&3
tip-ring or ring-tip switch for outputs 2&1
MIDI output jack 2&1
LED showing input MIDI activity
tip-ring or ring-tip switch for input
MIDI input jack

M-261 is one-to-four MIDI thru module. There are two “standards” for MIDI-through-jack connection, one uses tip-ring, the other ring-tip logic. M-261 can process both types of MIDI input and MIDI outputs. And of course it can be used as simple buffered MIDI converter between tip-ring and ring-tip logic.

Connect input MIDI patch cable and toggle the input switch so that the led blinks when the source device sends midi messages.
Connect some output to the target device and check if it receives MIDI messages. If not, press or release appropriate output switch.
There is no danger of destruction, simply try proprer switch position to make MIDI devices working. At first, the input LED should blink.

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