This circuit is better than the previous one in that the control is isolated by a transformer. The transformer has 110 or 220 V primary and 6.3 to 12 V secondary with 200 to 500 mA current.
This circuit was originally designed for the practice of Morse code, something common in 1966, the year...
This circuit is from an English magazine of 1977. The circuit is still current, just using a TIP41...
This miniature railway control circuit was found in an English documentation from the 1980s. The...