[ELECTRON] PHP - question. . . webcam script...again(ish)

[Clive Mitchell]

many of the car to USB adapters use a fairly efficient switching
regulator chip, but if the Arduino can support a low operating voltage
it might be possible to run both the phone and Arduino from a single
large lithium cell or NiMh battery pack.

Sometimes it's quite surprising where current is being wasted.  Power
indicator LEDs for instance.  Often run at 10 to 20mA but still
perfectly visible at 1mA or less if an efficient LED is used.

How did you find the whole interfacing of the phone to the Arduino?  I
bet it took a while to get it all sorted out.  Does your software edit
out morse sweary words?  :)

It's worth mentioning that lead acid batteries are really intolerant
of being over discharged  If they are discharged too low they may
suffer from plate sulphation which limits their future ability to
supply current and take a charge.

On 23 April 2010 10:19, Ben Dembroski <ben at dembroski.net> wrote:
> There is a 12v lead acid battery that is powering the phone and the arduino
> via a car cigarette -> USB adapter.  The other is an array of a bunch of
> AA's powering the beacon.
>
> Clearly, this isn't the most efficient setup with a bunch of the power being
> lost to heat through the volatage conversions and whatnot.  However, the
> system is robust (so it seems) and the batteries were cheep.   I suppose
> it's also worth mentioning that battery isn't really an issue.  The python
> script crashing is the real reason we've been out doing service calls...
>  We've just been changing batteries out since we were out there anyway...



-- 
Clive Mitchell.

http://www.bigclive.com