Warning. Don't remove battery with usb power

Ben Wilson ben at abcom.co.nz
Tue Mar 4 11:23:07 CET 2008

Yeah, without knowing how the power system is done i dunno either.

It could be the charging circuit going to max output to try and raise 
the battery volts above the min level, (which of course it can't). 
Whatever the cause, the scream is definitely coming from a coil or 
inductor vibrating due to the attraction/repulsion between its own 
magnetic field and the earth's. But which coil/inductor and what's 
causing it to go into this state i dunno.


Tilman Baumann wrote:
> Ben Wilson wrote:
>> Hey Nick,
>> I've not looked at the electronics inside the neo myself but the sound
>> is typical in the electronics world of a switchmode power supply 
>> under grate strain.
> The reason is a bit more banal. (AFAIK)
> The scream has just the frequency how much the main cpu can boot and 
> detect that there is no battery and reset. (something like that)
> Probably not a good thing for the components, but not a result of any 
> stress to the power drivers.
> But maybe it results in stress for them...
> Don't know. Better avoid it. :)
> Regards
>  Tilman Baumann
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