This circuit multiplies the input voltage by 3 and can work with up to 12 V input. The current is a few mA. We found it in the Radio Electronics magazine of December 1992.
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...