In the 110 V network, capacitors of 200 V or more and in the 220 V network, capacitors of 400 V or more, can be tested in this simple circuit. The indication is given by a neon lamp.
Found in a 1969’s EDN, this circuit provides 4.5 V with a 100mA current for digital logic. The...
We find this circuit in a 1980s Linear Technology documentation. The circuit can be implemented on the...
Found in Elektor Electronics from the 90s, this circuit can generate signals from 1 kHz to 9 MHz,...