Using the NE5205 integrated circuit this circuit was found in the May 1987 issue of Radio Electronics magazine. It can amplify signals up to 450MHz.
We found this amplifier for hearing aids or hearing aid using only transistors in a documentation from the...
Found in an English publication from 1977, this circuit uses only 1 LED. Unlit means heads and lit...
We found this circuit in an old documentation. The indicated solenoid is of low current type,...