Micro Research ERD/γ (Gamma)


Radioactive random voltage source.

ERD/γ digs the Eurorack synth deep into geological time scales of radioactive decay. The module provides a radioactive source (Uraninite aka. Pitchblende), Geiger counter and processing to deliver both pure random voltages and random timing/triggers.

Given the half life of the isotopes within the active material (Uranium-238 and Uranium-235) the module must be returned for recalibration in perhaps a few billion years.

According to selected mode (four CV modes) ERD/γ outputs a scaled random control voltage (0-5v) either at specific adjusted time deltas, or at scaled random times. A low entropy mode allows for faster random CV out (maximum 100-150Hz as compared to 10-20Hz). A trigger mode supplies the last available random voltage on trigger in (rising edge). A dedicated trigger out provides a 5v pulse (200uS duration) at random scaled intervals (at zero speed scale each pulse mirrors a beta decay event at the geiger tube). Timing and voltage scales are under CV control; local entropy can thus be reduced.


  • 35 mA +12V
  • 4 mA -12V
  • 0 mA 5V
  • 35 mm deep
  • Ø 4.40 (5 Votes) Average Rating

This Module is discontinued.

12 HP Random
submitted Dec 23rd 2015, 19:41 by micro_research | last Change Sep 29th 2016, 02:12 by acgenerator

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