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 uses a crystal phone and can be built with more modern transistors like the BC548. The...
The resistors in this circuit marked with * must be within 1% tolerance. The circuit is from the...
The existence of field effect transistors at the input of the integrated circuit (operational...