Moog Music MF-105M MIDI MuRF (Manual Addendum - Firmware v1.8) - Manual (Page 26)

PEDAL INPUTS: All pedal
control input jacks are 1/4" tip-
ring-sleeve (stereo) phone jacks.
The sleeves are grounded and the
ring terminals are supplied with
+5 volts which is current-limited.
The tip terminals receive the
variable voltages from the pedals.
An expression pedal for use
with the MF-105M should contain
a 50KOhm or 100KOhm linear
taper potentiometer which is
connected from the sleeve to the
ring terminals. The potentiometer
wiper is connected to the tip
page 26
Figure 14 - EP-2 compatible wiring,
Figure 15 - wiring diagram for using
external CVs with a TRS plug
terminal. The pedal cable should be shielded, with the shield connected
to the sleeve terminal. See Figure 14.
When connecting one or more pedal control input jacks to a source
of external control voltage such as an analog synth or a MIDI-to-CV
converter, you should use patch cords with tip-ring-sleeve phone plugs.
The ring terminal on the plug should not be connected to anything, so
that the MF-105M’s source of +5 volts is not shorted out. See figure 15
for a diagram. If you do not plan to use any expression pedals with your
MF-105M but would like to apply control voltages to one or more pedal
control inputs, you can use patch cords with regular two-conductor phone
plugs. These will short out the +5 volt supply to the ring contacts. This
voltage is current-limited, so you won’t burn anything out, but no pedal
will work in any of the pedal control jacks if a tip-sleeve plug is plugged
into any of the pedal jacks.
Applying a varying voltage to the tip terminal of a pedal control input
jack has the same effect as turning the corresponding knob. On the MIDI
MuRF, with the knobs in the mid-position, a voltage change of 0 to + 5
Volts at the tip terminal is equivalent to turning the corresponding knob
through its entire range from full counterclockwise to full clockwise. You
can ‘program’ your MF-105M performance parameters entirely from
external control voltages, by turning the ENVELOPE, MIX, and RATE
control knobs to mid position, and feeding 0 to +5 Volt programming