Looking at the Technical Reference Manual, there is a reverse-polarity diode in series with the negative (center pin) of the jack. This provides basic reverse-polarity protection but will also cause a small voltage drop (typically 0.6-0.7 volts) between the DC input and the main power bus. If you feed the usual 5.0 to 5.3 volts from a USB power pack into the DC input, this would cause the main bus to only receive 4.3 to 4.6 volts. The "Low Power" point on the 102 is listed as 4.1v so the unit may still operate.
-Josh On Fri, Nov 27, 2015 at 7:18 PM, Fred Whitaker <[email protected]> wrote: > You could make a short adapter to plug into the Model-T that reverses the > polarity of the connector. My question is,"Is the output adequate?" > > Sent from Outlook Mobile <https://aka.ms/blhgte> > > > > On Fri, Nov 27, 2015 at 1:20 PM -0800, "John R. Hogerhuis" < > [email protected]> wrote: > > On Fri, Nov 27, 2015 at 1:01 PM, Mitch Parker <[email protected]> wrote: > > John, > > > > How many hours can you run a pi from one? I have quite a stash myself, > and > > they are all between 2000 and 2600 mAh. > > > > Thanks, > > > > Mitch > > > > Not sure haven't measured. I guess it depends on which one. They seem > to range from 300-700maH. > > So these small juice packs give you a few "portable" hours. > > -- John. >
