Hi, Dave

> With those voltages and currents, why not use Russell's design to step
> the 74 volts down to 24, then Roman's circuit to step the 24 volts down
> to 5?  Russell's circuit is probably more suited to the high-voltage
> part of this thing, especially if you need 300 milliamps out of it.

    Russel's circuit for the pre-regulator is one of the ideas I had in
mind. I will have to think it out and experiment with different options
because I will be driving just pneumatic control solenoids and the lower
voltage supply from the 24 volts. I can use some sort of current controlled
solenoid driving or a power supply controlled by the CPU because I know
exactly when I will need the power for the solenoids. To make the decision
harder I will only have one solenoid on at each time, so the current
comsuption is very previsible. The solenoids just stay on for a maximum of 9
seconds each.

    At least I have many options to choose from :-) Another problem is that
I can have some nasty spikes on the 74 Volts power line that I need to take
care.

    I will surely let the list know how it is going. After all power
supplies are the only part that is present in any of our projects :-)

Best regards,
Alexandre Guimaraes

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