I found tis circuit in na old documentation from 1958. The circuit uses germanium transistor availble that time and hard to obtain today. The circuit is indicated for phono applications using variable reluctance transducer.
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....