|Re: Battery charger question|
Message #2 Posted by Steve on 18 July 2000, 8:08 p.m.,
in response to message #1 by Matthew Riehl
The charger is probably just a simple transformer, possibly rectified (I'm not sure about this model).
The change in frequency will not damage the transformer (it will probably make it more efficient though).
My recomendation is to get a resistor of appropriate resistance to simulate the load the calculator will place on it. Measure the voltage across the resistor (if it's simple rectified AC, then a capacitor in parellel may be a good idea). Then do the same thing for the 400Hz aircraft supply. A difference of more than (say) +20% would worry me.
Are you air-crew? if not, they might not like you pulling out a multimeter etc... :-) If you are, then I'm sure you could ask engineering staff the same question. In fact you could probably ask them anyway. If you can find an older engineer that had (has!) an old HP calculator you may have found someone who would care enough to answer.
The other (and maybe better) alternative is to go to www.pprune.org (Professional Pilot's RUmor NEtwork), register yourself, and ask the same question in the technical forum. (While you're at it, maybe you could say where you came from and we might find some more HP calculator users :-)