Using a higher rated DC transformer

["Connah" <connah@xxxxxxxxx>]

Good morning, all.

I have an electronic device that requires a DC Wall transformer rated
for 12VDC at 600 mA. Unfortunately, I have lost the power supply and I
cannot find another one with that exact rating. My friendly Radio Shack
representative tells me that the device only "pulls" what it needs from
the transformer, the transformer does not "push" that much to the
device. He tells me I can use a 12vdc at 1A for the device and it will
work.

Is this true? I do not want to fry my device by "pushing" 400mA more to
it than it needs. If he is right, may I use a transformer rated for
12vdc at 2.5 amps protected by the same principle? You can tell I'm not
an electrical engineer. :) I would appreciate any thoughts. Thank you!

Matthew