The transistor used in this circuit is uncommon today. AC124 or equivalent such as AC188K and 2N2431 can be used. The circuit is from the 80's and makes use of transformers.
This simple circuit of a question-answer minicomputer with tray was found in a 1987 magazine. The...
This receiver for listening on the phone was found in a Japanese magazine in 1967. The circuit uses...
We found this circuit in a 1977 publication for radio amateurs. It serves to test general purpose...