Here is some interesting information someone else wrote:
Last month I bought a Maha powerbank battery belt pack
for my Canon S20. It took me some time to modified the
DC Coupler to connect with this belt pack. Unfortunately
it only can last less than 20 shot before camera felt
low battery and shut down automatically. It's so strange
because this guy is rated 1800mAh and suppose to be able
to take tons of photos before next charge.
Today I used a multimeter to measure its voltage and was
surprised to find that Canon S20 would complain low-batt
when voltage was lower than about 6.4V. It's unbelievable
since a new duracell 2CR5 is measured only 6.3V or less.
How can a 2CR5 work well?
Finally I got the reason. When I use DC Coupler to power
up S20, the battery status shown in Zoom Browser, which
is a software provided by canon, is 'AC Power'. Seems that
S20 discriminate voltage requirement between external AC
input and battery. But how can it know it's an DC Coupler
but not 2CR5 or NB-5H?
After comparing it to 2CR5, I saw a metal contact on the
top of DC Coupler, which is different from 2CR5. Then I
decided to cover a paper on that contact to isolate it
from a spring contact in battery compartment. Know what?
It worked!
Wow, it means I can use LCD viewfinder unlimitedly. What
a exciting news. I'm so glad because I've thought this
belt pack totally a garbage and planed to throw it into my
trash bin.
I thought it may be useful to guys who also make battery
pack for S20 yourself so I post it here. Sorry for poor
English.
Regards,
Leo
P.S. I did the work in a hurry and forgot to measure the
voltage of that odd contact. Is there anyone who has DK110
can do it and post the result? Another concern is that as
far as I can remember, NB-5H does have 3 contacts, too.
Do you guys have any idea about it? Does it mean Canon can
recognize different battery by measuring voltage in this
odd contact? Post your result if you can get it done.
