elv wrote in post #16787094
So if the battery is running straight to the capacitor, do you think its possible to connect a high voltage battery pack (330v) in any way? Or does this need to stay 11volts like the original battery?
the capacitor i'm talking about its not the main capacitor, its just a small capacitor to smooth and stabilize power. "tecnically", i believe HV Battery packs can be connected to any flash, but im not qualified enough to be able to do it
i think most battery packs have 3 pins, 2 for direct connection with the main capacitor and a control signal to start/stop charging. if i had a oscilloscope to analyze it......
elv wrote in post #16787094
I was going to suggest the modeling light mod to you btw, that would be very handy having he remote On - Off control on the FT-16.
yeap, i think i will get power leds and do it... but will take a while to get all the components....
EDIT: did a few measurements...
Turned off: 10 µA
Idle with FT-16s: 40ma
Charging capacitor(at full-power): 4.8A (looks like it's limited to this)
the consumption "turned off" is way way lower than i expected, so its safe to let the battery inside for a few months with no problem whatsoever.
the circuit looks very efficient power-wise, low heat generated inside, so this should reflect in "long longevity" (but time will tell )
as current looks limited, its safe to li-ion with large capacity/low impedance with no problems (Yn-560ii for example doe not have limit, DIY battery packs can burn the flash unit)
so good so far. finally a cheap and DIY friendly li-ion flash
now i realized i can run 2 flashes with one battery pack (1 flash = 1900 full-pops, 2 flashes = 900 full-pops). will make them with two output connectors on each battery pack, so i can use 4 flashes with 2 packs
A simple way to calculate flash power is to use the power in watts for each pop. the V850 uses about 0.032Watts per pop, the YN-560II uses 0.045Watts per pop. so we see that a efficient circuit and the higher voltage of the battery makes +25% more efficient than "AA batteries flashes".
EDIT 4: More measurements...
3 BAR 12.60V ~ 11.35V (3.78V/CELL)
2 BAR 11.35V ~ 10.95V (3.65V/CELL)
1 BAR 10.95V ~ 10.60V (3.53V/CELL)
BLINK 10.60V ~ 5.20V (1.73V/CELL)
The flash measure voltages between capacitor charges, which is very good, and also good average voltages for resting li-ion cell.
its a good idea to replace the battery when the indicator start to blink (empty), the flash will try to get all the power from the battery, but constant "emptying" the battery at low level may reduce life cycles.
also, as current is limited, its very easy to use a AC power adapter to power this flash, and use as "studio flash" (just need to be 12V at least 6A like this). a voltage regulator can also be used (6A minimum recommended), PC power supply, 12V lead-acid battery, etc...
opened the battery, they use "Great Power 1800mah" (?) flat cells, with a protection circuit board that monitor each cell. as most batteries that use series cells, this do not balance cells, but monitor each one to avoid overdischarge/overcharge (require matched cell and charge state)
looks like the charger use the standard CC/CV charging, without balancing.
tested the battery, it really is 1800mah (measured), making around 0.032W consumption per pop