This circuit has an accuracy of 1%. The components used must be precision as well. The input frequency range is 40 Hz to 10 kHz with the indicated components.
We found this simple receiver with germanium transistors and listening on a crystal phone in a...
For the 1 MHz frequency, the pass band of this filter is only 120 Hz wide. The filter is suitable for...
Current drain with a 6 V supply is only 6 µA. Frequency is given by the capacitors, and output...