Envelope Follower

In conjunction with a voltage controlled amplifier, this instrument produces and envelope wich is the replica of the envelope of an applied "command" signal. Replication of the command envelope is accurate over a 60 dB dynamic range.

http://cluboftheknobs.com/pro_c912.html

• ? mA +15V
• ? mA -15V
• ? mA 5V

No info about availability.