This peak detector has a memory to prolong the response. The circuit is from American documentation from the 1980s. The supply does not have to be symmetrical.
The LM380 is not a modern component and in some cases not easy to find. But if you have one you...
August 2016 - Mouser Electronics already has in stock the new MCP1501 voltage references from...
This filter was found in old Raytheon documentation. The circuit makes use of operationals of the time, but...