The Bubba Pure Sine wave oscillator 60Hz with simple turn on button this can by replaced with 1 TTL pulse ( The normal automatic starting part of the Bubba oscillator circuit create a difference between the positive and the negative wave form voltage from 0volt ) ,And the outputs + sine wave pulses make it easy to use ,The potentiometer set output voltages ,Output voltage range are from Bubba ocsillator output voltage to maximum amplifier positive power voltages e.g. +15Volt.
