CV/gate adapter cards for 208

These cards are a plug and play CV/gate interface to control any 208 with standard 1V/oct CV/gate controllers.

The standard card features 1 CV input and costs pre-built 150€ VAT and shipping excl.




The dual card features 2 CV inputs  and costs pre-built 200€ VAT and shipping excl.




Please contact me to order.

Users manual

BOM and build notes

Features :

Pulse generator
- gate in minijack : gate signals between +5V and +15V
- LED displaying the incoming gate signals
- pulse out banana : typical pulse to patch to the 208 pulse input - can be wired internally to the 208's pulse input

CV 1 to 1.2V/oct adapter
- CV in minijack : for 1V/oct incoming CV
- CV out/in banana : patch to the 208's voltage from keyboard input with multiturn trimmer to scale to 1.2V/oct or 2V/oct - also works as an input to the MO and CO scaling circuits
- bypass mini slide switch located on the PCB behind the panel : switch to the left if the 208 is calibrated to 1V/oct to bypass the scaling circuit
so that the incoming CV is available as is on the CV out/in, the MO and CO direct CV scalers are still working
The dual card features 2 identical adapter circuits, either can be routed to either oscillator.

Individual MO and CO internal CV inputs via switches (no cable required)
- MO CV switch : connects scaled CV internally to the MO, adjust with trimmer and multiturn trimmer for fine tune
- CO CV switch : connects scaled CV internally to the CO, adjust with trimmer and multiturn trimmer for fine tune
On the standard card the switches can be replaced by banana jacks to patch to the frequency and pitch panel inputs if prefered.
The dual card features 3-position switches to connect either CV to the MO and CO.

Rear edge connector
To plug another card, like on the other Portabellabz expansion cards