sb 900 nikon flash DIY mod

[Rustyhands]

hi everyone,

has anyone found a good external diy battery pack mod for the sb 900. not sure of the connections on the front of the flash but looking to hook it in there. should be 6V. if that is clear to me i think i ll just go ahead and design one .

cheers rusty

[nirofo]

Originally Posted by Rustyhands

hi everyone,

has anyone found a good external diy battery pack mod for the sb 900. not sure of the connections on the front of the flash but looking to hook it in there. should be 6V. if that is clear to me i think i ll just go ahead and design one .

cheers rusty

The connection on the front of the unit are for high voltage input from the Nikon high power battery packs SD-8A SD-9, not low voltage 6volt supplies. If you want to make your own 6volt pack it will have to be via the battery compartment, easy to do if you're handy with the tools and a soldering iron, just make sure you identify the correct polarity for the 6volt battery connections. Have a look at the web links below for some ideas, there are probably others if you Google for them.

http://blog.davidburren.com/2003/03/...ower-pack.html

http://www.aljacobs.com/cables-for-f...s-flashes.html

http://photo.net/photography-lightin...s-forum/00VoM0

nirofo.

[Rustyhands]

cheers, nice links. i ve started building this today should be done tomoz and then make some dummy batteries

[Rustyhands]

yeah made the whole design and its ready to go but i have no power to the unit with the door open.... does the flash have a limit switch in it to say its closed and ready togo??

[nirofo]

It's probable that you don't have a good solid connection with the battery terminals in the flash unit if you leave the door open, can you get power if you press down firmly on the dummy batteries to make sure you have a good contact. You need to cut a small notch in the bottom of the door to let the wire come through with the door closed, it shows you where to do this on one of the web link instructions. If you don't want to do this then you can either put something round the unit to hold the door tightly closed, or, the best way is to purchase a spare door from a Nikon service centre and adapt it for the wire to come through. Check your connections to make sure you have then correct, here's a photo showing the connections for a Nikon SB-800, they're the same for the SB-900.

nirofo.

[Rustyhands]

hi mate,

yeah i understand the theory of it but i am not getting any response from the flash :S does it need 4 dummy batteries in the sb 900?? i cant see how it would change anything. voltage onto the series circuit for the batteries. got me baffled. i press down as hard as possible and still no voltage. all tests of with a meter and still it doesnt work. very interlesting

[nirofo]

Originally Posted by Rustyhands

hi mate,

yeah i understand the theory of it but i am not getting any response from the flash :S does it need 4 dummy batteries in the sb 900?? i cant see how it would change anything. voltage onto the series circuit for the batteries. got me baffled. i press down as hard as possible and still no voltage. all tests of with a meter and still it doesnt work. very interlesting

See ammendment to my previous post.

nirofo.

[nirofo]

Here's a schematic of what the actual connections from flash to external battery should be, it's very important that you get the polarity correct otherwise you could end up blowing your flash.

nirofo.

[Rustyhands]

cheers for the schematic.... sorted the problem. got lazy and just used dowl as dummy aa s but then replaced it with two threads

[mightypain]

Originally Posted by nirofo

Here's a schematic of what the actual connections from flash to external battery should be, it's very important that you get the polarity correct otherwise you could end up blowing your flash.

A bit of an off-topic, but I love your hand-writing!