Designing a classic transistor-VCA from scratch

Support the channel: Working simulation on falstad: In this double episode, I’ll walk you through the process of designing a classic transistor-based VCA (voltage controlled amplifier). The goal is to first de-mystify the bipolar junction transistor (BJT), its usage in a common emitter amplifier plus its two central flaws (variations between seemingly identical samples & temperature dependence), before then exploring the differential amplifier (also known as the long-tailed pair) and how we can get it under voltage control. Inverting amp in-depth explanation: AC coupling in-depth explanation: