[ARC5] Those +/- 48 Volt DC-DC Converters

[David Stinson]

Concerning those DC-DC converters that make good
100 Volt DC supplies-
I've learned "the hard way" that they don't like to be surged
on the input.  I "bobbled" 24Volts on the input 
and blew one, probably because of the filtering inductance
on the ARC-5 receiver A+ buss.
Filter caps on the input?  Back-bias diode like with a relay coil?
Any other simple ideas on protecting the inputs from intermits
and surges?