Cap, You proposed the idea of tapping the batteries. I would suggest that that wouldn't be a good idea. Al later briefly mentioned the big problem with this -- unequal currents being drawn out of the PC supply. Generally the minus voltages are required to supply only a few tens of milliamps, The RS232 serial port being a major consumer for its require plus and minus swing. On the other hand the + 12 is usually called upon for the hard disk drive motors and voice coil actuators, so it runs in the several amps. The +5 is the real killer. It runs in the many amps for the processor and logic. Additionally on the ATX supply used with Pentium class machines you need the 3.3 V supply at lots and lots of current (tens of amps), You can see the pinout at: http://www.technick.net/cgi-bin/frames/loadframes.cgi?http://www.technick.net/pinconmth_atx_power.htm The upshot of all this is that one section of your tapped battery will be discharged and as you attempt to charge it, you will burn up the other side trying to send charge current through it to the discharged side. And if you've never smelled the odor of an overcharged battery in the morning, it's not a good one. (I was in the two-way business in my early days, and we kept batteries under the bench to feed the "dyna-grinders" in the transmitters. Think about that one, old timers!) Regards, Chas. __________________________________________________________ Public Seismic Network Mailing List (PSN-L)
Larry Cochrane <cochrane@..............>