This circuit of a Popular Electronics from the 90s makes use of components of the time. The circuit has sampling and retention capabilities and a conversion rate of 1V / kHz.
This circuit was obtained in the publication 101 Electronics Projects of 1979. The circuit can be...
This Popular Electronics circuit can be found in various versions on this site and in this...
This circuit for analogue TV was found in an American 1980s documentation. The transistor can be any RF...