This circuit for the 40 MHz band was published in Radio Electronics magazine in December 1957. Its purpose was to monitor the signals of the Russian satellite launched at the time.
This application of the RCA integrated circuit released at the time was found in the August 1970...
These basic filters, the second one being operational, were published in the November 1973 issue of...
This circuit adds the voltage from the secondary of a transformer to an outlet connected to the...