Hughes suggests this circuit in a 1968 documentation. The circuit uses old transistors that can be replaced with equivalents. MOSFET is the critical component of the circuit.
This flood or humidity alarm was found in an English publication in 1991. It can still be fitted...
This simple transistor tester uses a common 3 mA analog instrument that has its scale changed as...
This RF amplifier step has a dynamic range of 140 dB and can amplify signals from 0.5 to 40 MHz....