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Adapter Question

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Sceptre

New Member
hey guys,

just finished moving apartments, i seem to have misplaced the adapter for my toshiba cable modem. The adapter was [email protected] (and that is whats written on theback of the modem).

only adapter i have kickin around is a [email protected] The modem will only draw what it needs right? this is the max the adapter can actually put out.

TIA


Sceptre
 

Agent 009

New Member
Euh.. I don't think so... If I understood your problem, you had a 1-A adapter, and now you have a 1.3-A power supply. So if you connect the adapter to the 1.3A power supply, it's very probable that you burn it, giving it .3A more than needed, unless it has some protection inside, like magnitude comparators, or current clippers...
 

Sceptre

New Member
my modem requires a 12vdc @ 1A power supply (wall adapter). Can i replace that adapter with one rated at 12vdc @ 1.3A?
 

crust

Member
In most cases yes, replacing it with nominally more current than it needs is usually ok. The difference is that there is some thevenin impedance in the wall wart. So measured with no load it might be 14V and with a 1A load it might be 12.2 or something (I am just guessing) since most of these arent regulated. The voltage at 1A will probably be slightly different than the original adapter. However, you need to check the polarity of the adapter, some are tip negative, while others are tip positive.
 

Sceptre

New Member
crust said:
In most cases yes, replacing it with nominally more current than it needs is usually ok. The difference is that there is some thevenin impedance in the wall wart. So measured with no load it might be 14V and with a 1A load it might be 12.2 or something (I am just guessing) since most of these arent regulated. The voltage at 1A will probably be slightly different than the original adapter. However, you need to check the polarity of the adapter, some are tip negative, while others are tip positive.
the original adapter is center postitive...the replacement i got there is center negative...can't i just cut the wires and reverse them?
 
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