I actually left it to charge overnight, but as soon as I unplugged it it would die on me Even though the green “fully charged” light was on.

I guess it’s a bit of a moot point though, as it’s better to charge the batteries with a dedicated charger that will be charging the battery at a lower mha rate than the Dana will (healthier for the batteries).

I charge the batteries with a dedicated battery charger, and switch out an extra set of freshly charged Eneloops while plugged into a USB charger so I don’t lose data during the switch. So far I’m digging the 4AA setup, though on the Alphasmart flickr forum there was some concern voiced over what kind of stress this may be placing on the device. So far so good, though (3 weeks).

Sorry for the very late reply; I haven’t been checking here of late

I seem to have problems charging the Dana un 4AAs. Long story short, plugging the device in (via USB or direct charging adapter) doesn’t fully charge the batteries —the charging light suddenly goes green, indicating a full charge even though the batteries are still weak.

My guess is that the Dana senses the higher output of the 4 AA’s but still thinks that there are just 3AAs in there, so the charging cycle gets stopped before the 4AAs get fully topped up.

Does anybody have any ideas how to fix this? Theoretically, maybe a resistor or a reverse-biased diode can be put in place to make the “load” look like 3 AAs again?

What has been your experience with 4 batteries instead of 3? Does it go longer between charges than the original mod? And for the life of the device itself, I wonder if this is actual something that should be done anyways, as the NiMh at 1.2v are putting out 3.6v instead of 4.5 with the alks. 4.8v seems closer.

But when I opened the unit up, I saw that there was ample space for one more AA battery. Strangely enough, there’s even a plastic slot at the end that can accept the springy “negative” battery terminal after the latter has been removed from its original position.

Any worries about “frying” the circuit were quickly dispelled when I realized that four rechargeable AA batts, at 1.2v apiece, would only deliver 4.8v of juice –whereas the Dana happily accepts 5v via its inbuilt USB ports. And, in any case, the output of the Dana’s factory-issued charger is a surprising 7.5v!

Pictured here ( http://farm8.staticflickr.com/7169/6418696231_c3d0a16e4e_b.jpg ) is my own mod, based on yours but with the “negative” terminal moved to the end slot. Note that the original plastic slot has been melted away and filed down to allow the fourth AA battery to easily slide in and out of place.

First, I’ll find out soon enough I suppose, but is the battery compartment ground connected to the battery pack ground? In that case, I think I can just cut out the positive “blanking plate” from a dead battery pack, and insert it into the battery compartment, and still leave everything connected? ie no surgery required to the AS itself.

Also, has anyone looked at adding backlighting, eg some LEDs around the display, or an electroluminescent panel behind etc?

I’m looking at installing ssh and a few similar things, I gather TuSSH supports alphasmart.
Of course the big limitation is WEP only 802.11b, but I also have an old palm bluetooth SD card, and my aim is to experiment using the AS as an “intelligent keyboard” that you can also take with you. In the simplest case it could be a “KVM” type keyboard with hosts listed and selectable on the touchscreen, for example.
Jack