This modulator circuit for low intensity signals is from old documentation. The integrated circuit used is uncommon today. The circuit operates with signals up to 2MHz.
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...