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(SolarWind) wrote in message . com...
"Jim Rex" wrote in message ...
Hello,

I have a pair of speakers that need a 13V and 2A DC power adapter or wall
wart. I lost its wall wart and found a wall wart for another device, which I
have no idea what its for.. it gives out 15V and 400mA DC.

The power adapter I found said on its back that it must not be used with any
other device except..[some brand name]...

Now, I used it with the pair of speakers and it worked!!! Now, i'm worrying
that this configuration could cause it to explode or something....

Will it do any harm???

It depends on the real voltages, not the marked ones. real ones are
often a fair way removed from what it says.

You may fry your wall wart, but if you keep the volume down to .4/2
times max it should be ok. Pulling 2A from a .4A wart is a bit
optimisitc.

To find 3 1N4002 power diode in serial with your power adapter before
the plug,
each diode will drop 0.7V DC, and 2.1V for 3 diodes total, the diode
cost is very low, you can find it in any electronic component shop:

just 2 tiny tech details:
1 rectifier diodes typically drop 1-1.5v on load, 0.6v is just the
turn on knee.
2 we dont know what the real Vs involved are

NT