Found in an Elektor from the 90s, this circuit makes use of current components. The input voltage depends on the relay.
This experimental AM radio circuit was found in a 1979 English magazine. It can be fitted with a...
This is a variation of the two previous circuits but controlling two LEDs. The brightness of the...
This circuit is the receiver for the CB13997E. The transistor can be the BC548. We also found this...