This circuit was found in Texas Instruments documentation from 1968. The transistors are from that time, admitting modern equivalents. The response ranges is from 20 to 20 000 Hz.
The circuit shown in the figure was found in a 1974 publication. The field effect transistor may...
I found this circuit in an English publication from 1989. This configuration can be mounted with...
We found this circuit in a small espionage manual from 1993. The components are current, and the...