This circuit was found in a1980s Motorola documentation. The integrated circuit is from that time. The frequency depends on the crystal.
This low-pass filter with 741 op and symmetrical source was found in the August 1993 issue of...
This RF amplifier step has a dynamic range of 140 dB and can amplify signals from 0.5 to 40 MHz....
This project from a 1983 publication can be assembled using more modern transistors. We can use...