Doepfer MTC64 Midi to Gate Interface (main board) - Manual (Page 13)

MTC64 V2 User’s Guide Page 13
Basic Test
The basic function of MTC64 can be tested very easily:
• Connect a low current LED (max. 2 mA) via a current limiting resistor (about 2 kOhm)
between output #1 and GND.
• Select the inverse polarity (JP7 / Jumper 5 installed)
• Connect the power supply
• The LED will light up if everything is OK.
• If now the MIDI message that activates output #1 (i.e. note on or program change
message) is sent to MIDI In of the MTC64 the LED will turn off. Otherwise you have not
chosen the correct settings (i.e. MIDI channel, mode, offset) and you have to check if all
settings are correct.
If no low current LEDs are available the following procedure will lead to the same results:
• Connect a LED via a current limiting resistor (about 470 Ohm) between output #1 and +5V
(one of the +5V pins of JP5).
• Select normal polarity (JP7 / Jumper 5 removed)
• Connect the power supply
• The LED will light up if everything is OK.
• If now the MIDI message that activates output #1 (i.e. note on or program change
message) is sent to MIDI In of the MTC64 the LED will turn off. Otherwise you have not
chosen the correct settings (i.e. MIDI channel, mode, offset) and you have to check if all
settings are correct.
Factory Setting of the Jumpers
In the factory all 9 jumpers are installed:
• Pin header JP6: all 8 jumpers are installed
• Pin header JP7: jumper 5 is installed (jumpers 1...4 have no meaning)
This corresponds to:
• MIDI channel 1
• Note mode
• Offset (= note number assigned to output #1): 0 (see remark 1)
• Octave transpose: +12 - 12 = 0
• inverse polarity (see remark 2)
Remark 1:
If you want to change the note offset (= note number assigned to output #1) to the standard
note number 36 (= lowest "C" of a standard 5 octave MIDI keyboard) jumper 8 of JP6 has to
be removed ! This applies probably in most cases.
Remark 2:
Same is valid for the output polarity. If normal polarity is required (i.e. +5V for active outputs
and 0V for inactive outputs) jumper 5 of JP7 has to be removed.