This circuit is from a 1965 General Electric hobby manual. The circuit can be assembled with sensitive reed relays.
This circuit that can amplify signals from 0 to 30 MHz was found in a 90s Popular Electronics....
August 2017 - STMicroelectronics' BlueCoin development environment is available at Mouser...
In this circuit the output current is limited by R3. For a 300 mA current, R3 must have 12 Ω. For...