With the disclaimer that I'm not an electrician, I would think:
* voltage should be the same;
* polarity of the DC output must be the same (i.e., which contact is Plus and which is Minus);
* if the substitute adapter is capable of higher power (Wattage) output than the original, that may
be OK; the device will simply draw less. If the substitue adapter is not capable of enough power,
that would be a problem.
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