This circuit was found in documentation from the 80s. It is based on unijunction transistors not very common today being synchronized by the 60 Hz power grid.
This circuit was found in a Mullard transistor manual from 1960. Note the symmetrical power...
This amplifier step with a transistor has an input impedance of 100k to 10 M. The transistor can be any...
I found this little signaling transmitter in old American documentation. The circuit has a good...