This circuit was found in a 73 magazine for radio amateurs from the 90s. The circuit uses high voltage transistors and the relay is high voltage as well.
This H-bridge shield circuit appears several times in applications in this section and on this...
This circuit can be used as a shield based on 555. The calculation of the timing network is done...
This circuit was obtained from a Popular Electronics of 1994. The magazine no longer exists in its...