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You are here: MIDI Drum Machine Photos Inside

MIDI Drum Machine
Main Page
Circuit Board Layout
MIDI Protocol Details

Inside Photo

Here's a view of what's under the hood.

inside photo

Back Panel: MIDI In, Out and Thru connectors (right side), alternate external inputs (left, bottom), and sensitivity adjustment knobs (left, top).

Center: Main circuit board.

Center right: Power supply transformer and capacitor (back), battery backup for user configuration (front), and a small breadboard that generates a reset signal (not actually used).

Front Panel: (Left to right) Power LED, "all notes off" pushbutton, 4 user-input pushbuttons (pad select, parm select, increment and decrement), currently selected pad display (8 LEDs), three digit parameter value disply, and currently selected pameter name (8 LEDs).

There is another similar inside photo, which shows a bit more of the lid and has a bit better view of the front panel, but the view of the circuitry is smaller.

Take a closer look at the circuit board.

Or go right to the main CPU schematic.

The MIDI Drum Machine, Paul Stoffregen and Rod Seely.
Designed and constructed Fall, 1991. Project status: Complete.
Last updated: February 24, 2005
-- These drum-machine web pages are still under construction --
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