I learned about this while watching YouTube videos by the Naval Postgraduate School (NPS). Whenever the HP 33120A 15 MHz Function/Arbitrary Waveform Generator was used to drive a speaker or other device this amplifier was used to raise the output power enough to so that the device would work. One happened to be on eBay when I looked and was at a reasonable price.
In some NPS videos a series resistor is inserted in series with the lower right ground terminal so that both voltage and current across the DUT can be measured. Usually with a dual channel scope.
Frequency range DC to 1 MHz with gain adjustable between 0 and 10X with up to 20 Volts peak output (10 Watts). Can be used a power amplifier or power supply.
Fig 1 Front 3/4" Dual Banana in and out
Note screwdriver Zero adjustment for DC.
Fig 2 Back BNC-f in and out
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