Found in a 1969 EDN, this circuit uses components from that time. Modern equivalent transistors can be used.
September 2017 - Vishay Siliconix SQ MOSFETs for automotive use are in stock for immediate...
This amplifier produces a few hundred milliwatts of Input 100 pF audio over a load of 4 or 8 ohms...
This circuit shows on the instrument the effective value or RMS of the input voltage. The diodes are...