This circuit allows the detection of RF signals using the lowest range of direct currents of a common multimeter. Equivalent diodes such as 1N34 can be used. The circuit is assembled in a ballpoint tube.
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,...