Found in Motorola documentation from the 1970s, this circuit makes use of period components. The lamp is used as a stabilizing device. The signal is sinusoidal.
This circuit, with printed circuit board, is from an article in Radio Electronics magazine from...
This simple transistor radio with only two germanium transistors was found in a Japanese magazine from...
Found in Radio Electronics from the 90s, this circuit generates signals in the 60 Hz to 1.4 Hz...