Sequencer Aux Card for the Buchla 208

Sequencer Aux Card for the 208

Sequential Voltage source
– reset sequencer switch
– 8 potentiometers for sending a voltage between 0V and (approx) + 13,5V

LFO/VCO (Triangle Wave)
– CV – Pot switch. Switch between controlling the LFO/VCO pitch using a CV signal or the
potentiometer
– Range Switch. Determines the range of the LFO/VCO. Lowest position gives LFO speeds, upper
position is audio range. This switch is CV controllable (more on this later...)
– Potentiometer for controlling the speed/pitch from the LFO/VCO

Portamento
– portamento time potentiometer
– MO & CO switches. The CO switch selects between keyboard input, off or sequencer input.
The MO switch is basically an on/off switch and only works when the CO switch is in the “key” or
“seq” position. You can have portamento on the CO only, or on both CO and MO.
When you're using portamento the keyboard switches from the MO and CO on the 208 should be
in the “out” position. Basically, both MO & CO switches on the card act the same as the keyboard switches from the MO
en CO on the 208 as in: they connect the keyboard pitch (or voltage) banana jack input to the pitch /
frequency bus on the 208.

From Prog
– Select switch. Selects which CV signal is presented at the “from prog”banana jack. Choose
between the Sequencer or LFO/VCO.

Seq Trigger
– Switch for selecting the clock signal for the sequencer. Choose between “Pulser” or “Seq” (the
208 sequencer pulse selected by the 5 switches on the 208 sequencer). Pulser position can be the
keyboard pulse instead, if that's more convenient...depends a little on how you use your 208.

To Prog 1 / SEQ
– Potentiometer for adjusting the amount of CV signal send to the destination selected by the
LFO/VCO switch below.
– LFO/VCO switch. Select between “Range” and CV . As mentioned earlier, the range switch in the
LFO/VCO section is CV controllable (like all three way switches on the 208). When selecting this
option the range switch should be in “low” positon. CV controls the speed/pitch from the LFO/VCO. (the CV – POT switch should be set to CV)
– Input selection switch. Choose between “to prog 1” or “sequencer”.

To Prog 2
– Potentiometer for adjusting the amount of CV signal send to the destination selected by the CO
WS (wave shape) switch below.
– CO WS switch. Selects the destination for the CV signal presented at the “to prog 2” banana jack
input. SW is the three way wave selection switch. Pot is the wave shape potentiometer.

Steps

– Switch between Random Voltage 2, OFF or Seq – LFO/VCO (the one that's not selected by the
“from prog” switch. This let's you control the number of steps for the 208 sequencer.

safety precautions:
– Always turn off the 208 when inserting or removing the aux card.