Found in a 1967 General Electric SCR manual, this circuit can be used to protect a load by switching in case of excess current. R1 determines the trigger current.
This current meter with many scales was found in a 80s American documentation. The operational amplifier...
This dimmer, from an old publication, can use almost any triac and in shooting a neon lamp. The...
We found this circuit in a 1975 publication. The circuit can be made with more modern equivalent...