Found a documentation on PCs from 1996, this circuit can be used as a shield. The relay is rated at 100 mA of coil current.
We found this circuit in an old Popular Electronics. The circuit can be applied to other...
With this circuit it is possible to receive the signals from the 11-meter band (27 MHz) in a...
We found this circuit in an American publication from the 90s. The transistors must be provided with...