I found tis circuit in na old documentation from 1958. The circuit uses germanium transistor availble that time and hard to obtain today. The circuit is indicated for phono applications using variable reluctance transducer.
This good gain antenna up to 30 MHz was found in an American 1990s documentation. The circuit can be...
This circuit was found in a publication from the 50's. The circuit uses germanium transistors of...
June 2016 - It can be purchased from Mouser Electronics the new triacs Z04 for 4 A from...