This circuit is from a 1968 Electronic Design. The characteristics of the output transformer are not given and the transistors are of the time. The circuit provides a power of a few watts.
This indicator was found in a 1974 publication, but it can be fitted with the BC548 transistor or...
This circuit was obtained in a documentation about old neon lamps. The circuit indicates when a...
The circuit shown is from a 1994 National Semiconductor technical documentation. The circuit can...