(26-04-2012, 01:50 PM)Mark Hennessy Wrote: Not sure how you're getting there, Al. Indeed, I'm not entirely sure how it's going to work at all, as the primary is not being driven at all well. I assume it's a 50Hz transformer...
Quite: I overlooked the simple fact that the sec'y. of the transformer is not producing a sine-wave.
Thank goodness for that; I knew I had missed something somewhere: my calculated watts for R5 was just not believable! 
So thanks for the correction. And like you, I don't care much for the design either. For example: Zeners in parallel: how can you be sure that there will be an equal distribution of current between them?
Al.
