PORTABELLABZ

CV/gate adapter card for Buchla 208 and Music Easel


This card interfaces your Buchla 208 or Music Easel with non-Buchla equipment.
It's plug and play and works with 208c, 208e, 208p, 208r rev2 and 70s 208.




A pre-built card costs 140 VAT and shipping excl.
Please contact me to order.


DIY sets will be available very soon from SAmodular.

Users manual

BOM and build notes

Features :

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

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

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
The switches can be replaced by banana jacks to patch to the frequency and pitch panel inputs if prefered.

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