Available as an assembled Module and as a DIY project.
This Module is currently available.
Rectifier/Multiplier
PRM is a multi-purpose analog operator for rectifying and multiplying signals. It is designed to cover as much functional territory as possible, while also remaining compact and intuitive. PRM is capable of many basic processing steps, such as half wave rectification, full wave rectification, four-quadrant multiplication, two-quadrant multiplication, and non-linear wave shaping.
These merchants probably sell this module. Huh?
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