!!top!! Fulltone Ultimate Octave Schematic

The internal bias trimmer (10k) is crucial. If it drifts or is set wrong, the octave disappears.

While Fulltone has never released an official schematic, reverse-engineered PCBs and unit tracing have revealed a consistent design. Here are the critical stages: fulltone ultimate octave schematic

If you find a hand-drawn schematic online, here is how to trace it visually: The internal bias trimmer (10k) is crucial