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mains adapter problem

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New Member
I have an Altai mains adapter.
Input 240v ac
Output 3,4.5,6,7.5,9,12 v dc
300mA MAX

It has a polarity plug where you plug in the lead.

I want to run a 3v Fuji film digital camera.

Do i plug in the plug so the + goes to the - or the + goes to the +?

Does it matter?

What happens if i plug it in the wrong way? Would that harm the camera?

Thanks in advance.




New Member

the + goes to the +. Now, I have a question for you.Is the adapter regulated or un-regulated? If its un-regulated I suggest you go and buy a regulated adapter, as an un-regulated one will output the wrong voltage at different current, running the risk of blowing up the camera!

Good Luck!



Active Member
Beware cheap PSUs


Just wondered what model Fuji you have/

I had the 4700 and it was ok but it ate batteries, and WILL eat your 300mA adaptor.

I know because I tried to make one from a 500mA adaptor and that wouldn't even power up the 4700. I finally got it to run on a 1000mA one but even then it required a very precise voltage control circuit or it would just turn on then off.

BTW when I tried the 300mA supply the stabilisation was not good enough and it killed itself AND the camera, the Fuji 4700 seems to have NO overvoltage protection and is very picky about supplies, (many of the small cheap multi adaptors have virtually no stabilisation at all!) maybe your Fuji is too! Be very carefull and good luck...........Al


I think the only reasonable solution is to buy the appropriate adaptor for the camera.


Well-Known Member
:) Another six-years-dead thread rises from the grave.



This is getting annoying, I should check the dates before forming a reply.
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