My understanding is that the zener impedance acts like an impedance in series with a perfect theoretical zener diode.

Or are you thinking about lowering the series resistance in the psu aswell? If so I think you are on the right track ðŸ™‚

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]]>(The half wave dual supply recifier will draw about twice the current from the transformer as a full wave single supply rectifier would, so the load should be equal to maybe 50-75mA if it were a single power supply).

Also take into account acceptable line voltage variations.

P.S. if you can, choose resistor and zener max power handling so the resistor blows first. It’s easier to find a replacement and the risk of damaging something more seems slighty less than if the zener blows. (I don’t know how zeners usually fail though).

P.S. I really like your blog and I think it’s great that you do all the work on your replica hardware!

]]>I have all the parts I need to build and test a unit on hand or on order. I figure it will take a couple of weeks to check the oscilloscope interface out. At that point I plan on offerring sets of the two oscilloscope boards, plus the keyboard PCBs. So figure 2 to 4 weeks, depending upon how much hobby time is available to me.

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