This filter for receiving audio in telegraphy was found in a magazine 73 for radio amateurs, in an edition of the 80s. The circuit is tuned to 700 Hz and has a 200 Hz bandpass.
Published in Radio Electronics magazine in May 1963, the purpose of this circuit is to visualize the...
This power supply for those who want to feed and recover 5 ¼ floppy disks was found in the...
This circuit uses currently uncommon components, including the 10.7 MHz (FI) filter. This circuit was...