Found in a 1969 documentation, this neon lamp circuit may have the number of steps increased. The power supply is made with high voltage.
This circuit is an application for an operational amplifier with field effect transistors from...
This circuit was found in a 1977 magazine, but it can be easily assembled today using BC548...
Found in a 90s Popular Electronics, this circuit uses a simple 9 V source. The power can be used...