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Halo Transformer Schematic

Posted by Triode_Kingdom on January 3, 2017 at 17:53:35:
Here's the schematic. This was drawn from the original 60W units that were common until about a year ago. The new units are slightly different. A diode is connected from the top of the Diac to the junction of the two transistors, and capacitors C3 and C4 are 0.47u.

It's necessary to add a filter capacitor (shown with dotted lines in the schematic). A value of 47u will yield a waveform like the one below. This level of 120Hz ripple will be inaudible if a hum pot is used.