This 600 kHz circuit is designed to locate a lost boat anchor. The circuit has a range of up to 10 meters. The transistor admits equivalent.
The cut-off frequency of the filter shown in the figure can be adjusted to values between...
This circuit was found in a Popular Electronics from the 90s. The components used are all common...
This circuit uses a dual floodgate MOSFET not very easy to obtain today. Its handling is very...