Professional Eurorack sawtooth-core VCO with discrete 2N3904/2N3906 exponential converter, TL072 square comparator, plus/minus 12 volt rails, precision passives, and a low-bleed 2-layer 100 mm by 50 mm layout.

Stereo 3‑Band Active Audio Equalizer and Mono Preamplifier using TL072 and LM386 with Right‑Angle PCB‑Edge CUI SJ1‑3535NG TRS Jacks for Jack Sensing and Routing