This power supply was featured in the December 1973 issue of Radio Electronics magazine. This type of circuit was used at the time to power tube televisions.
We found this receiver circuit for modulated light in a 90s Popular Electronics. Equivalent audio...
This field strength meter circuit was found in the March 1968 Radio Electronics magazine. The...
I found this circuit in a 1998 publication, but as all components are common, it can be easily...