This interesting circuit for analog TV selects the first line of a frame. The circuit was found in a 1967 Electronic Design. A modern equivalent transistor can be tried.
This radio version with a transistor for a crystal phone was found in a Japanese magazine from...
For the component values used in thisf this circuit, the frequency can be adjusted between 740 Hz and...
This simple source is indicated for voltage regulators of 5 A x 12 V as the one found in CB17141E. The...