Converting mains battery charger for 12v operation

[Daniel Kelly (AKA Jack)]

Hi,

I have a Canon XL1-S camcorder with a CA-910B mains charger (this is the
charger that comes with the camera as default). I'd like to convert the
charger so I can power it from car battery.

I've taken the lid off the charger. I think I can connect an 8.45volt DC
source across the smoothing capacitor after the transformer and rectifier
diodes. Does this sound sensible? I figure that all I need to do is build
a regulator circuit that will produce 8.45v from 12v and pump this into the
charger over the capacitor (C22)..

However, I'm not very experienced at these things and I'd be enormously
thankful if you geniuses (or genii?) could have a look at the PCB. I've
scanned it...

The large images are LARGE (400 kbytes). I've flipped the top side so it
matches up with the track side

LARGE images
http://www.ucl.ac.uk/~ucgadak/charger_tracks_large.jpg
http://www.ucl.ac.uk/~ucgadak/charger_merged_large.jpg
http://www.ucl.ac.uk/~ucgadak/charger_components_large.jpg


SMALLER images (for those with slow internet connections)
http://www.ucl.ac.uk/~ucgadak/charger_components.jpg
http://www.ucl.ac.uk/~ucgadak/charger_merged.jpg
http://www.ucl.ac.uk/~ucgadak/charger_tracks.jpg

Many many thanks,
Jack