Compaq (off topic)

Snip! And Chuck's comments on batteries snipped as well... To clearify; Main battery is charged by two types of process; charging (or rapid charging) and trickling charging. Still, the voltages and currents used to charge that main battery does changes. Example: 12V NiCd rated at 2000mAh battery pack, uses 10 cells in series. Rapid charge is around 1amp or so in order to get under 2 hours and around 2V rapid charging voltage per cell. That's why usually I see 18V power bricks paired with portables that uses 12V NiCd pack plus that said power pack also stated around 2A max or so in order to meet both rapid charging AND have some enough current left over to power a running portable. Trickling charge is around 1.3V or so per cell with controlled current to give very low current around less than 100mA or less to that pack. Norminally fully charged voltage is 1.25V per cell. Max commented on 3 batteries in a portable like this LTE Lite, That little pack with 6 cells is 7.2V standby battery pack. In certain situations for example if you wanted to swap batteries in midstride without cutting power or reboot that machine or put a computer in deep sleep, that part dips into that pack for this. Anything else ususally uses cmos battery either 3.0V lithium coin or 3.6V NiCd battery. First thing you will see problems on those CMOS battery is bad time keeping when pc is off or in deep sleep in extended time and at worst problems powering up and down or losing cmos data configuration. Both Lite and Elites uses siimple power bricks norminally 12~18V around 2A max, no sensing feedback from computer. Just like a coax plug but in Compaq's infinite wisdom used oddball 3 pin connector. Grr. Yes, I did split those power brick for that Lite and Elite when I check for solder joints, it's simple PSU no tricky extra circuits anything else besides simple PWM circuit. Charging circuits is inside that battery pack with that yellow LED indictor. Jason D. PS: For several reasons, I always split open all power bricks when I aquire anything that is portable or whatever or is tasked to repair any portables at component level work IS to check on the condition of those capacitors and solder joints condition. One of my SLT power brick died because of this by clusmy user who had no idea that PSU is not working right before me! Blown PWM IC, couple of resistors burnt to crisp and no one dropped in to tell me those two resistor values when I requested these info and power MOSFET (expansive as hell at around $15 to $20 each and hard to ge). BTW, that SLT power brick is model 2682 or 2687 but it's lighter depsite it's same size but the DC power cable is *deatachable* from power brick. Anyone have that one? If so, find 2 screws under that rubber feets and would be mucho appreciated to report on those resistor values for this R500 and R512??? They're dull green fusiable resistors in 1/4W size connected directly between that MOSFET switcher and the PWM ic. Thanks! Jason D. jpero(a)pop.cgocable.net