kony <spam@spam.com> wrote
> Rod Speed <rod.speed.aaa@gmail.com> wrote
>> kony <spam@spam.com> wrote
>>> Rod Speed <rod.speed.aaa@gmail.com> wrote
>>>> kony <spam@spam.com> wrote
>>>>> Rod Speed <rod.speed.aaa@gmail.com> wrote
>>>>>> kony <spam@spam.com> wrote
>>>>>>> Rod Speed <rod.speed.aaa@gmail.com> wrote
>>>>>>>> Noozer <dont.spam@me.here> wrote

>>>>>>>>> If I have an external phone modem that uses a 1amp 9vDC tranformer,

>>>>>>>> That would be unusual.

>>>>>>> True, but if it is really 9VDC, next is to determine how much current it
>>>>>>> uses (if there's a multimeter handy) or the more conservative (higher)
>>>>>>> equipment current rating, or the overly conservative and probably less
>>>>>>> useful original PSU (wall wart?) current rating.

>>>>>>> I seriously doubt it comes remotely close to 1A,

>>>>>> Plenty of mine are of that order.

>>>>> The wart might be, but I doubt the modem itself is.

>>>> Plenty were, most obviously those that came in an
>>>> extruded aluminum sleeve and got quite hot anyway.

>>> Quite hot and overheated are not the same thing.

>> Never ever said it was. It is a reasonable indication that
>> it might well be using something of the order of 9W tho.

>>>>> If it used 1A @ 9V, that's of course 9W (practically
>>>>> all heat generated internally), and nothing gets that
>>>>> hot to the touch or needs significant heatsinking.

>>>> Which is why quite a few of them came in an extruded
>>>> aluminum sleeve and got quite hot anyway.

>>> See above.

>> See above.

>>> That is no proof of any particular heat density

>> It is a reasonable indication that it might well
>> be using something of the order of 9W tho.

> No,

Yep.

> given any wart will be conservatively spec'd,

By nothing like as much that stupid claim you made
about 250mA you just plucked out of your arse.

> we can be sure the power consumption is _below_ 9W

Duh.

> and quite possibly much lower.

Nope, no chance. And nothing like that stupid claim you
made about 250mA you just plucked out of your arse.


>>>>> Measure, it's the only way.

>>>> I doubt too many would bother to supply a
>>>> 1A wall wart if the modem only needs 250mA

>>> Whether the figures is close to 250mA or not,
>>> we can assume the supply current is rated
>>> higher than the device by a reasonable margin.

>> Bet its nothing like that sort of margin.

> A bet would be silly, measure it.

It wont be anything like that stupid claim you made
about 250mA you just plucked out of your arse.

> Since I don't have the OP's unknown model of modem here
> (or maybe I do, kinda hard to say...), the best approximation
> would be from other consumer devices using warts.

Wrong again, the best approach if it isnt possible to measure it is to
assume that the wall wart he said he wants to replace isnt that over rated.

> They are typically spec'd to not have peak (continuous)
> consumption over 75% capacity, if even that.

Still nothing like that stupid claim you made
about 250mA you just plucked out of your arse.

> To put it another way, if they provided a 9V, 1A wart and it
> was using 1A of power, that alone is a good reason to stop
> using it, as it will be getting quite hot and short lived if
> in the typical sealed plastic wart case.

Stupid to not just replace it with an adequate wall wart.