Can I substitute a 6v for a 4.5v power supply?

I just bought a portable CD player whose specs call for a 4.5V/300mA power
adapter. The player doesn't come with an adapter, just two AA batteries. I
found a couple of adapters in my house that are 6V/300mA. Can I (safely) use
these adapters in place of the 4.5V the specs call for?

Gary

 

No, this would probably damage your CD player. However, if you splice a
a resistor into the low voltage line, 5 ohm half watt, you have made
yourself an unregulated 4.5 volt/300 mA adapter.

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Gary,

Something does not fit. Two AA batteries account for 3V max. Most of the
time it will be less. For 4.5V you would need three batteries. So if your
battery box only has place for two batteries - and the CD player works fine
with it - 6V will be a substantial overkill. It may even worse when the
converter is unregulated. If you have a regulated 6V converter you can
nevertheless use it but you have to use three diodes - let's say 1N400x - in
series. If you have an unregulated supply, you have to add a regulator
circuit. A new converter will be much easier and even cheaper.

petrua

 

It does seem strange, but my CD player uses 2 AAs and it is marked 4.5 volts
on the DC input and, in fact, came with a 4.5v wall wart. My digital camera
uses a 3.7 Li-ion battery and comes with a 5v AC adapter.

These devices have an internal power supply that converts to several
voltages as a computer's PSU for the various electronics inside. While the
OP's CD player may work with the 6volt adapter, the dissipation may be
excessive and damage the player.
John

 

Which is why he posted in the first place.