This interesting circuit for SMD assembly appeared in the November 1987 issue of Radio Electronics magazine. The phonons are generated by selected resistors that are fitted to the assembly.
This amplified circuit was found in a magazine for radio amateurs 73 of the 90s. The circuit uses an...
We found this circuit in a 1980s publication on espionage. The transistors support modern...
This 6-transistor receiver was manufactured in Japan in the 60s. The circuit is superheterodyne and has a 6V...