This power supply for model railroad was found in a February 1961 Radio Electronics Magazine. The transistor must be mounted on a heatsink and the transformer is a 1,5A secondary winding.
We find this circuit in a 1980s documentation. The integrated circuit used is unusual today. The...
Found in a 1968 Mullard manual, this circuit measures temperature by infrared radiation. The...
In the figure we have a monostable that is activated with switch S1 and pressed for an instant. The...