Doepfer MBP25 Midi Bass Pedal Electronics Kit - Manual (Page 8)

MBP25 Page 8 User's Guide
(4) Bass Pedal Connectors
These female connectors are used to connect the bass pedal(s). The connectors are
compatible to the connectors of the Fatar PD/3 bass pedals and the same type of
connectors are used (AMP micromatch 16 pins). To connect MBP25 with the bass
pedal(s) 16 pin ribbon cables with a 16 pin male connector on each end is used. The
connectors are equipped with code pins that have to fit into the corresponding hole
on the MBP25 and PD/3 pc boards. Otherwise the pin may break off. Please check
the correct polarity of the code pin before you put up the connector. If the connector
is put up in the wrong way the bass pedal will not work but there is no risk to damage
the electronics.
If only one PD/3 bass pedal is used it is connected to ST1/LOWER.
If two PD/3 bass pedals are used the lower is connected to ST1/LOWER and the
upper to ST2/UPPER.
If the pc board is mounted to a front panel the ribbon cable connected to ST2/UPPER
has to be bended by 90 degrees to lead the cable lateral from the display.
It is possible to connect even a third bass pedal to the MBP25 electronics. In this
case a special ribbon cable with three male connectors has to be used that leads
from ST2/UPPER to two bass pedals. In addition the feedback line of the third pedal
has to be wired manually to the solder pin labelled JP1/MK4. If you want to connect a
third pedal please contact us concerning this special cable and wiring as we do not
offer a package with 3 pedals (use the email address [email protected]).
If you want to use the MBP25 not in combination with the Fatar bass pedal PD/3 but
with another bass pedal (or even single contacts or switches) the contacts have to be
wired as a diode matrix. You find the corresponding schematics at the end of this
manual.
(5) Connector for Volume Control
Remark: In the following the terms GND (= abbreviation of ground) and 0V (zero
volts) are used synonymous.
The pin header ST3 with three pins is used to connect the volume control. The pins
of the connector have these functions:
Position Function To be connected to ...
left GND
end terminal #1 of the potentiometer
(the terminal that corresponds to Midi data 0)
center
measuring input (control
voltage)
center terminal of the potentiometer
right +5V
end terminal #2 of the potentiometer
(the terminal that corresponds to Midi data 127)
The wires leading to the potentiometer can be soldered directly to the pins of ST3.
But it's also possible to use a prepared standard 3-pin female connector with cable.
As the potentiometer is used as a voltage divider between GND and +5V the
resistance value of the potentiometer is not crucial. Any value between about 5k and
500k (linear) will work.