This RF preamplifier for the 450 MHz band was found in an amateur radio documentation from the 1980s. The transistor supports an equivalent operating at the recommended frequency.
In this circuit the capacitor under test is charged at switch position A and then discharged...
This is a common circuit in the 1990s, when experimental FM transmitters were in vogue. The...
Using a piezoelectric sensor of the time, this circuit was found in the February 1994 issue of...