Found in a publication by Gernsback from 1960, this circuit uses germanium transistors of the time and commercial coils. It can be changed to operate with modern transistors and other wavebands.
P1 on this Radio Shack circuit is a 6 V lamp with current up to 500 mA depending on Q2. The...
This simple touch alarm, found in a 1995 documentation, uses common components and a triac to...
With the micro voltage regulator shown in the figure, we can design a power supply for small...