This circuit was found in a 73 magazine for radio amateurs of the 90s. The circuit uses two types of indicators, the diodes are for general use. The power supply is 5 V.
This circuit can be used in demonstrations or science fairs. The circuit uses headphones and can...
We found this wiretapping circuit in a publication from the 90s. The circuit allows the cable...
This circuit uses a resonant reed switch at the trigger frequency. The circuit is from General...