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AUDIO DEMOS


  • Long Sequence [5.9 MB].
  • Raw Ratios [420K].
  • Rhythm [876K].

  • Arpeggiation [3.1 MB].

  • MOTM-730 VC Pulse Divider
    $399 assembled & tested

    The MOTM-730 is a PIC microprocessor-based digital module that takes an input signal and generates lower frequency square waves at multiples of the input frequency. It is a "big brother" to the MOTM-120 Sub-Octave Mux (in divide mode): the '120 divides by the multiples 2, 4, 8 and 16. The MOTM-730 can generate multiples from 1 to 33, as well as 'half' multiples (1.5 to 16.5). There is also an 8-step, positive-going sawtooth wave that has 3 user-selectable step intervals.

    The MOTM-730 requires the 6-pin MTA-156 power connection (+-15V @16ma, +5V @100ma). For more info, download the User Guide.


    DIVISOR OUTPUTS

    Each divisor output runs independent of the others. The only thing in common is:

    - All use the same input clock, and the same edge as set by the switch
    - All outputs are 0V to +5V square waves (not AC coupled, but DC coupled)
    - All respond to RUN/STOP

    The outputs are driven by 74HC244 line driver ICs with a 100ohm series resistance. The outputs are done in this manner to easily trigger/gate MOTM-800 envelope generators and control MOTM-190 VCAs. You can also treat the outputs as audio, but before sending these signals to a mixer/amplifier, you need to pass them through an AC coupled module first (like a VCF, or the upper channel of a MOTM-190).

    /N - this output will follow the setting shown in the LED display, as set by the addition of the front panel setting and any applied control voltage.

    Fixed divisors - remember, the silkscreen on the panel is for the FULL setting! Switching to HALF means the outputs speed up by 2X (because the ratio is 1/2 of the printed setting).

    STEPPED OUTPUT

    This output is a positive-going (starting at 0 volts and incrementing upward), 8-step, sawtooth waveform. There is 1 step at 0V, and 7 successive steps of positive voltages. The amount of each step is set by the panel switch (as 'heard' by applying this output to a VCO). The voltage is fairly accurate, but not really accurate. If you want to 'tune in' a more precise interval, use the OCT (octave) range (1V/step) and apply this to the FM IN of a VCO. Then, you can 'dial in' what the interval is. This was just a fun, cheap added output. Use it to drive VCOs, VCFs or audio, too (has a nice raspy tone).