Good point, with the P76 being for the new LiMH-packs, but my chargers are much older.
Their transformer still designed for the old mains voltages from over 30years ago (110V/220V).
I could only find photos of both on the web, with zero explanation of difference of function
709: 6.8V 400mA
729: 7.0V 600mA
I can only surmise that the 729 is able to bring a set of batteries to full charge 50% faster.
So either larger capacity cells, fully charged in same amount of time, or same capacity cells charged in 50% less time;
but charging voltage is not indicative of charging cells of a different chemistry (like NiMH)
You are too modern for me, I am still living in Nicad days.
Those Nicad chargers basically are just a transformer, at the cages there is a diode network, That's it. Your NiMH charger must got some microprocessor or such.
Metz Flash Charger Metz 970 for NiMH Battery 76-56 & 45-56. NiMH battery 45-56 For 45 CL 4 digital, 45 CL/CT 1, 3, 4, 5 (NiMH charger required!). The NiMH 45-56 battery allows photographers to shoot a minimum of 220 flashes at full power; a 175% increase from the previous NiCad 45-40 battery.
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