Bipolar transistors are types of general use like BC548, while the power MOSFET can be of any type depending on the current and voltage in the load. The circuit is from old documentation.
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This circuit triggers an alarm when the mains power is cut off. The circuit was found in the July...
This acutely tuned circuit was found in American documentation from the 1960s. The transistors are germanium...
This small AM transmitter was found in American documentation from the 1980s. Transistor support...