It sounds as if the cap stores enough energy to save the clock´s time, but not the power the mainboard long enough until the file is written. The clock´s time needs much less voltage to be saved.
I also read here that other users had also problems with the caps sold back in the days.
I recently bought two caps from ebay (
https://www.ebay.de/itm/10F-2-7V-2-Stück-Low-Voltage-Supercap-Small-Size-Double-Layer-Kondensator/332862026104?ssPageName=STRK:MEBIDX:IT&_trksid=p2057872.m2749.l2649) no advertisement)
and attached them to the case. I used the connector cable of the old battery. It does´nt look nice, but works perfectly. The wiring of the caps is not covered yet, to check the caps voltage.
I noticed that the caps needed some seconds (~30 seconds, I haven´t measured it) until they stored enoug energy to save the last file.
But that is only relevant if the cam hasn´t been used for some days. After they have a certain voltage level, you can switch on / switch of the cam within seconds without any problems.
I haven´t tested yet how long the time is saved. The cam is operational by now and that´s enough for my.
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