Nominally, a charged NiCd gives one 1.25v per cell. These are 6-cell packs, so that is 7.5v for the pack. In reality, a NiCd will hit 1.4v right off the charger, so that's 8.4v if you measure it before too much time has passed. The voltage of a fully charged NiCd will sag down in about 6 hours.
A NiMH pack is slightly different in the voltage drop vs. capacity, but they will show 9.0v right off the charger and then drop off more slowly than a NiCd, staying above 8v for a week or so.
In use, the NiCd voltage stays at 1.2v per cell for a long time, until it has around 10% remaining, when it starts dropping like a lemming off a cliff to 1.0v per cell at which time it's done. The NiMH will drop off at a fairly constant rate until it hits 1.0v per cell, at which time it, too, is done.
The total capacity of the NiCd will be on the order of 1200 mAH and the NiMH will be around 1500.
My 760c will fill slightly over 2 GB worth of storage on one NiMH pack, and the 720x just slightly under 2 GB. That's using solid-state flash cards, not the more power hungry microdrives (if anyone is still using those, that is). My 560 is the same as the 760c, which makes sense given the same size imagers. the 720x does not get as far GB-wise as the 760c as it has to fire the camera a lot more to fill that card.
One thing about the older 560 vs. the newer 760 is that the 560 will work with NiMH packs that are no longer up to their original capacity. The 760 will take a couple shots with a worn pack and then tell me to get a new battery. The older packs will sag more voltage after a shot is taken and stored, and I think the newer firmware in the 760 is looking at the battery voltage either much sooner after a shot, or is programmed to look for that extra sag and then call the battery done.
In any case, if one chooses to go the bench power supply route, set the voltage at 7.6 volts and the current limit to 500 milliamps and you'll get almost a full charge (90%) into the NiMH pack without risking production of oxygen and hydrogen in the cell and ruining it.
Keep firmly in mind that a NiMH cell can not take *any* overcharge the way a NiCd cell can. No trickle charging, please! Make sure it cuts off at 90-95% or it will not live for many cycles.....
A real NiMH charger like the Kodak ones we can't get pump more current into a pack, but watch the temperature rise and then back off the current until it winds up turned off. Since the bench supply has no temperature monitor capability, we have to set the current lower and simply take a bit more time to charge then the real charger does. But, it is a cheap solution that works well if you have nothing better.