# Blackmer gain cell

> four-transistor log-antilog voltage controlled amplifier for professional audio designed by David Blackmer

**Wikidata**: [Q22582422](https://www.wikidata.org/wiki/Q22582422)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Blackmer_gain_cell)  
**Source**: https://4ort.xyz/entity/blackmer-gain-cell


## References

1. [Source](http://www.google.com/patents/US3714462)