This sophisticated repellent uses a double 555. We find it in an American documentation from the 80's. The circuit can be powered by batteries or source included in the diagram.
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...