This is the transmitter for a remote-control system published in the August 1986 issue of Radio Electronics magazine. The circuit uses two 555 CMOS transistors to drive two series LEDs.
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...