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Arfa Daily Arfa Daily is offline
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Default Shorting DC power supplies together


"Salman" wrote in message
oups.com...
I connected an 9.4Vdc 400mA power supply for external pc speakers to a
12V power supply line from the back of my Dell 20" FP LCD monitor
intended for an optional "speaker bar" that Dell sells. Suffice to
say, neither the monitor nor the dc power supply are working. Anyone
know what to look for to repair the monitor? Is it salvageable?
Possible just some components near the power supply outputs needing
replacing?


I would start by looking for fuses / circuit protectors / safety resistors.
These may not be too obvious, as they likely will not look like something
that you would traditionally identify as a fuse - ie a glass or ceramic tube
with end caps. Many fuses in this type of equipment, are about the size of a
1/4 watt resistor, and are wire ended. Circuit board silk screening may call
them "F", "CP" or "ICP" and there might be a rating also silk screened on.
Other types look like a little cylinder, and have a rating written on their
flat top. Still others, are surface mount, and are usually about the size of
the surface mount decoupling caps that you see scattered all over boards
these days. Finally, if a safety resistor type, then it will actually look
like a resistor.

Arfa