On 10/01/2014 11:52 AM, trader_4 wrote:
....

How so? The battery is rated at X amphours. Whether it delivers it through
a diode or not is mostly insignificant. Only a very small amount of power is
lost in the diode.

But what's significant is what _fraction_ of the power consumption any
portion might be...if the overall is also pretty small as one would
expect/it must be to have a long battery life to begin with, that "very
small amount" may still be a decent fraction of the total and then the
decrease in lifetime is proportional to that fraction.

Again, this is all _purely_ hypothetical w/o any other data...but if the
symptom exists that the battery life doesn't appear to be any longer w/
AC powered unit than non-, it's pretty clear there must not be any real
power-saving circuitry inherent in the device design (or, the overall
device power consumption is quite high and therefore drains the battery
at about the same rate even though there is some extension over what it
would have been w/o the AC).

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