This circuit is from a Radio Electronics from October 1963. The transistor is a power transistor of the time, and two transformers are used. The input has 10k impedance and is powered by 12 V.
This circuit is from a 1995 publication. The components are all common and the number of LEDs may...
Found in a publication from the 60's, this circuit makes use of germanium transistors of the time....
We found this circuit in a 1972 documentation. The transistor, in fact, is a unijunction that can...