This circuit was suggested by Motorola in a 1969 publication. It makes use of components of the time, but both the FET and the bipolar may be general purpose current types.
We found this circuit in the 1964 RCA transistors manual. The transistors used are uncommon today,...
The output voltage of this circuit is proportional to the square root of the input voltage....
This 5-band function generator circuit was found in the April 1994 Electronics Now magazine. The...