This amplifier for the 10 m (30 MHz) band has a gain of 12 to 15 dB having been found in an American documentation. Other RF transistors can be used like 2N2222 or 2N2218.
With this circuit it is possible to divide the frequency of a rectangular signal by values between 2...
This circuit, which we find in a documentation from the 70s, filters out the Ru [occurring in...
This circuit simulates the call tone of a telephone. The transducer is a high impedance capsule, and...