The basis of this circuit is the HA2400 released at the time. The circuit is from a Radio Electronics magazine from March 1980. The power supply must be symmetrical at 15 V.
This traditional metronome configuration uses unusual transistors in the original version, but it...
This circuit was found in Texas Instruments documentation from 1968. The transistors are from that...
This sensitive field strength meter was found in 1993 documentation. The instrument may be the...