Found in a 1924 publication, this 2-valve receiver has a speaker output. Power comes from several batteries. Information about the coils is given.
This reaper has the signal limit determined by the zener voltage. We found this circuit in a 1980...
This unity gain circuit was found in the February 1995 Electronics Now magazine. The frequency is 10 kHz,...
This reinforcing stages from a 1960s documentation. No information is given about the transformer...