This circuit uses an HA2400 consisting of 4 digitally controlled operational amplifiers. The circuit is from a Radio Electronics magazine from March 1980. The power supply must be symmetrical.
This circuit was obtained from the November 1989 issue of Radio Electronics magazine. The circuit is...
This simple digital frequency meter using CMOS circuits reaches 5 MHz frequency. Input signals are...
We found this circuit in the 1960 Mullard transistor manual. The transistor is made of germanium....