Re: External battery pack for N8x0/770.
 

Got my cable today. It works great, and it has a microSD reader too (on the other side of the usb connector actually, extremely small).

http://i136.photobucket.com/albums/q...martcable1.jpg
http://i136.photobucket.com/albums/q...martcable2.jpg

Re: External battery pack for N8x0/770.
 

Thanks. You could post a link if you think it's worth it for others to purchase.

And let us know if it melts or burns your house down!

Re: External battery pack for N8x0/770.
 

http://www.usbgeek.com/prod_detail.php?prod_id=0788

It seems really nice...sturdy... then again if i dont show up here for a week ive burned to death ;)

Help - Tekkeon MP1550 + 4xAA Sanyo Eneloop 2000mAh = 1 hour extra battery time?!?!
 

I'm hoping those of you who have had success using the Tekkeon MP1550 as an external power supply can help me out here.

I have two MP1550's, several USB-to-Nokia-2mm charger cables, and quite a few sets of batteries including alkalines, lithiums, and NiMH rechargeables. Among the rechargeables I have 2 new sets of 4xAA 2000mAh Sanyo Eneloop batteries (Several folks here have posted positive results using Eneloops with the MP1550).

With the N800's battery topped off and the Eneloops fully charged I'm seeing no more than 60 minutes of power before the 3 LED's go dark on the MP1550. With Energizer e2 2500mAh and Duracel 2000mAh NiMH's I'm only seeing 40 minutes. Alkalines and lithiums go pretty quick as well - not that I'm interested in using disposable batteries. I'm testing using Mplayer running a full length movie (384k video / 96k audio) with screen at 40% brightness and volume at 50%. I get these results using either MP1550 with any set of batteries and any one of the several USB charging cables I have.

I'm pretty discouraged at this point. I'd assumed from the positive reports here that the MP1550 would work well for my N800 as an external power supply but with these numbers the MP1550+batteries is just extra weight. Does anyone here have any suggestions?

Thanks!

Re: Help - Tekkeon MP1550 + 4xAA Sanyo Eneloop 2000mAh = 1 hour extra battery time?!?
 

I'm not sure if this is related but I thought I'd post my new findings useing the Tekkeon MP1550...

I've been using the MP1550 for quite sometime now and have found that if I use the retractable cable that can with the MP1550 to connect to the device and then proceed to use the device at the same time - my N810 battery level pretty much stays the same. That is my battery is neither charged or depleted (well maybe a percent or 2 but not much). This is using Ultralast NiMH Rechargeable AA (2000mAh) Batteries. A fully charged battery pack will last for several days with my usage.

However, I've just recently ordered and started using a Nokia CA-100 cable (I didn't like how far the Tekkeon cable stuck out from the side - it didn't seem to fit well). And the Nokia CA-100 appears to pull a lot more juice from the batteries. Since I've started using this new cable with the Tekkeon I've noticed that now sometimes my NIT battery is actually charged (ie: the battery percentage increases). However, my fully charged Tekkeon battery pack now only lasts a couple of hours before all the green lights go out.

So, I suspect that there is a great deal of difference in the cables. My husband said that if the CA-100 cable had resistors in series (or was that parallel :o ) that it could be pulling more power from the battery pack. What do you guys think?

Re: External battery pack for N8x0/770.
 

The ca100 has a step-up converter, and probably it properly handshakes with the tablet so that it draws more current (there's a nokia specification for chargers that says how much current a phone should draw depending on the voltage the charger provides at start-up).
Note that I don't have a ca100 cable, I gather it has a step-up converter from the specifications.

Re: External battery pack for N8x0/770.
 

luca, it seems you may have a deeper understanding of some of the electronics issues pertaining to charging cables and chargers. Do you see any danger to the NIT in using the cheaper third-party cables and chargers, or in using ones that don't have a "step-up converter"? Thanks in advance.

Re: External battery pack for N8x0/770.
 

Not really, I just asked on this forum if it was safe to use a car adapter and somebody posted a link to the charger specifications.

No, the only risk is that it probably won't charge the n800 fast enough to keep the battery charged while using it, or it will take a longer time to fully charge it if idle, anyway I cannot really say, since I never use an usb cable to charge my tablet. I can only say that the cheap car charger I bought from dealextreme is working fine (crossing fingers ;))

Re: External battery pack for N8x0/770.
 

Alright - thanks for the feedback! The cable that came with my first MP1550 was faulty and so I chose to not use the one supplied with the second MP1550. I'm testing now using the supplied retractable cable and adapter and so far all three status LED's on the MP1550 have remained solid for 4 hours. Sweet!!

The only downside is that the bulky Tekkeon Nokia adapter seems like it could more easily facilitate damaging the N8X0's power than the standard charging cable should the cable or adapter be accidentally pulled laterally. This would be easy to avoid at a table in a cafe or some other setting where you have plenty of space. I'd be a little nervous sitting in coach on an airplane with someone sitting to my right though.

I'm going to contact Tekkeon on Monday to order a replacement cable for the one that arrived faulty. I'll also ask them if they have specifications for the supplied cable/adapter and pass along any useful information here.

Thanks again all!!

Re: External battery pack for N8x0/770.
 

I am using a cheap usb cable i bought off of ebay that seems to work fine charging from my laptop. The ca100 knockoff on deal extreme is probably going to be better though, and it is cheaper too.

I have been wanting to buy an external battery pack, but I want something cheap. I would also prefer to get a 1xAA or 2xAA pack instead of a 4 one so that it is less bulky. any suggestions? I know about the minty one, but is there anything cheaper?

Re: External battery pack for N8x0/770.
 

I tested all of the cables that I've used with the MP1550 so far (USB to Nokia 2mm) for resistance. All cables measure less than 1ohm for the negative conductor. The results were different measuring resistance for the positive conductor between the MP1550 Nokia adapter and the other cables. The Tekkeon Nokia adapter measures 5.8ohms resistance while the other cables measure less than 1ohm. I'll order a 5.76ohm resistor from Mouser and use the cable from a Nokia AC-4U charger to see if I can make a better power cable to use with the MP1550.

Re: External battery pack for N8x0/770.
 

I'm curious about these solar chargers: http://usb.brando.com.hk/prod_detail.php?prod_id=00304 and http://usb.brando.com.hk/prod_detail.php?prod_id=00314

The whole green idea is enticing, though has anyone had any experience with these? My previous experience with the Solio Charger did not turn out well as it took two days to completely charge the battery.

Re: External battery pack for N8x0/770.
 

Solar chargers are not "green". They will produce more CO2 manufacturing them than you will save from using them.

Solar panels are only effective when they are mounted on the roof and exposed to sunlight the entire day. But even then it takes years for them to "break even" as far as the environment goes(and even longer for your wallet).

Don't get me wrong, solar panels are great, but there are a lot of people out there that are going to try and make a quick buck off of other peoples attempts to "go green", and at the end of the day it ends up hurting the environment. Donate the 70 bucks to an environmental charity and you will be doing a lot more good than by buying that snake oil charger.

Re: External battery pack for N8x0/770.
 

This is getting offtopic here, but I'd just like to point out to contradict your statement that the Solio chargers are 100% carbon neutral; the company plants a tree for every device purchased, and I don't have the exact numbers but they're on the site somewhere... it's something like every unit requires X amount of energy to produce, and if used every day for a week saves the end user X + 10 amount of energy.

As far as performance, just don't try to use the thing through a tinted automotive window (even a slight UV protection tint) as it actually blocks the energy from getting to the solar panels. (ever tried to wear those "transition" sunglasses in a car with a UV tinted windshiled? same problem)

Re: External battery pack for N8x0/770.
 

Thought I'd post a quick follow-up. I used the cable/plug from a Nokia AC-4U charger, a 5ohm resistor, and a male USB connector to make a new power cable to use between the Tekkeon MP1550 and the N800. The 5ohm resistor is in series between the +positive connectors, the -negative connectors are connected directly. I used a few layers of heat shrink tubing where the splice was made and the cable is rock solid. I've been running Mplayer video at full screen brightness and full volume for about four hours now. The N800's battery still shows full and I have 3 solid status LED's on the MP1550.

Thanks again for all of the feedback! :)

Re: External battery pack for N8x0/770.
 

Excellent deal on excellent battery pack discussed on this thread.

IOGEAR GearJuice Mobile Pocket Charger for $19.99, free shipping. Works well, small form factor, nice design, adapter perfect for N-series. N-series AC adapter even the right size to charge the pack. Also has adapters for Motorola cellphones, etc. I'm very pleased with it.

Re: External battery pack for N8x0/770.
 

The iogear looks very interesting, but I was also looking at this other battery made by eGear, a manufacturer I'm not familiar with. http://www.amazon.com/eGear-Universa...9929503&sr=8-1
It claims a "4280mAh" capacity, though the reviewer estimates at 5v its less. Any thoughts?

Re: External battery pack for N8x0/770.
 

I just thought I post a quick update to my Tekkeon 1550 + Official Nokia usb->power cable usage. I had said in my previous post that once I got the Nokia cable that the batteries in the Tekkeon started running out of juice pretty quickly and it was pointed out that the Nokia cable pulls more from the charger than the stock cable that comes with the Tekkeon. This allows the Tekkeon+Nokia Cable to actually charge my device as opposed to just keeping it at a constant level.

Well, last week I picked up some Sanyo 2700 batteries and must say - these are incredible!! I was expecting a ~30% increase (my previous batteries were 2000 mAh) in the amount of use I would get out of a fully charger set in the Tekkeon, but instead I'm seeing ~70% increase in the amount of time between recharges :D I used to have to recharge the batteries in the Tekkeon pack every day because I used it frequently throughout the day to top off my N810 battery. Now with the same amount of usage I'm able to go for almost 3 days before I have to recharge.

If you use your portable battery pack a lot and it can use AA batteries - you've really got to get Sanyo 2700 (I also read that Duracell 2650 are good but can't speak from personal experience).

Re: External battery pack for N8x0/770.
 

has anybody look at this one, http://www.boxwave.com/products/batt...pter/index.htm. +S/H = $27. Just an alternative choice to Tekkeon 1550. They claimed "up to 5 fully recharge cycle", with 4 AA battery? I doubt it.... Just trying to avoid the Nokia Ca100 cable for $39.95. Oh well...
Battery adapter pro.

bun

Edit: How about this one too, http://www.amazon.com/APC-PNOTEBX-US..._cr_pr_sims_t?
APC USB battery extender


Edit:
Using a USB charging cable "SIDO" ($5.99 from ebay), to charge from a laptop (an old PC) to N800 from a dead battery (wont boot, or shut down after showing a red battery icon, not the yellow one with exclaimation mark), 30 min charge while the tablet is showing the charging icon (i.e., the tablet is NOT on) gives 2 squares on the battery icon, like 50% juice. And the laptop is NOT plugged in. I have also tried a 2XAA battery charger using 2000 mAh recharging batteries, it wakes up a 770 from dead battery, but it cannot wake up a dead N800. Upon charging, it charges the N800 for ~1 min then it refuses to charge. So far, the only one that is giving consistent results, wake up the tablet and charging the tablet is charging via USB port of a notebook PC. Any comments? Old news? Sorry.....


bun

Re: External battery pack for N8x0/770.
 

bun, I'm not sure if this is responsive to what you're saying, but ...

At least if you're using fanoush's boot menu, you need to make sure you haven't selected that last option, the one about being off with no charger plugged in. I used that one the first time with my IOGear battery pack and it managed to drain the battery pack and at the same time not increase the charge in my N800.

Re: External battery pack for N8x0/770.
 

got one of these on rebate at buy.com:

http://www.buy.com/prod/powermonkey-...206229850.html

works phenomenally well and the solar unit actually works to power up the battery. Reviews have been very positive for this. Comes with the Nokia tip but also includes a USB plug tip so it will work with anything that charges via USB.

Re: External battery pack for N8x0/770.
 

You can't fool everybody, znutar! You live in Snohomish and you're telling us how well a solar charger works!! But you need the sun for that!! :rolleyes:

Re: External battery pack for N8x0/770.
 

No. I am using Fanoush's boot menu, but I did not choose the last option "...no charger plugged". my 2X AA external charger cannot wake up the N800, it gives a screen of "...hold menu to get boot menu...". It does wake up the 770 though. Anyhow, I browsed thru the whole 180+ posts, found out that most people use as a supplement battery while the tablet battery is full. I will try that tonight.


bun

Re: External battery pack for N8x0/770.
 

Do you know what the capacity for this battery is? Out of all the batteries I have looked at, the eGear offers the best as far as capacity, looks, and price. It also has a battery meter, upping the proporta or javoedge battery in, I guess, usability.
The Tekkeon was appealing, but I realized NiMH AA batteries just don't hold their charge long enough (unless you own a pair of eneloops, but thats besides the point). Though the flexibility is a nice feature. But at 4280mAh at $30, thats pretty dang good.

Re: External battery pack for N8x0/770.
 

I've used my IOGear battery backup to charge a totally-exhausted-to-shutting-the-N800-down-automatically battery, and it charged it. I wish I could help with whatever your N800's problem is, I was just making a guess based on my experience.

BTW, exhausting the battery like that seemed to get its capacity back to what it was originally, more or less.

Also BTW, I'm going to buy one of those solar Powermonkeys znutar posted about. I'm an easy sucker for an $80 rebate.

Re: External battery pack for N8x0/770.
 

I still remember my Physics 101, charging a battery has to do with the difference in the voltage between the charge source and the charge destination. I think the voltage between 2 AA battery and the N800 is simply too small to be working. While the laptop computer or even just 4 AA battery is large enough to do the job. I think I can still make use of this 2 AA battery charger, I will test it to run with an N800, see whether that would increase run time.


bun

Re: External battery pack for N8x0/770.
 

@ Bunanson - I picked up the Nokia CA100 cable off of Amazon for $15 total here's the link: http://www.amazon.com/gp/offer-listi...0079898&sr=8-1

Seller was good, shipping was fast.

@Geraldko - LOL!! I've often thought the same thing about using solar chargers here :P Everytime I think of buying one - I'm able to talk myself out of it. I did buy at flashlite/usb charger that uses a human powered cranking mechanism to charge batteries though.

Re: External battery pack for N8x0/770.
 

I am disappointed.
How long can your system run continuously under this test conditions: I want to use a stressed condition, so as to see an endpoint quick. Here is my stress conditions, Volume is set to max and back down just a touch, worry prolong playing with max vol may damage the small speakers. Running kmplayer 93 world TV, playlist 99TV4IT8d.m3u.txt, dl here please, http://www.internettablettalk.com/fo...ad.php?t=19044, with volume almost to the top and video brightness to the top. (kmplayer will play continuously)

On my freshly top off N800 battery coupled with my newly acquired battery extender using a set of two 2000mAh freshly charged battery, it ran only 135 min!

I quickly switched with another set of freshly charged 2000 mAh and the program continue to run without a gap. Now I switched to VideoCenter and running CBS KatieCouric Evening news continuously (media player>player>mode>repeat). Apparantly, if I can catch my battery extender before it dies, I can replace with another set of charged battery and keep on going, so far so good, it has been going on for another 1 hrs so far...

So, under this stressed use, a top/freshed charge N800 + 2 sets of 2000 mAh AA batter, so far, it is running into 3 hrs and 10 min.
N800/2007.51-3/MMC boot.

Tomorrow, I will try to run the same setup without battery extender and see how it goes and different configuration, including internal flash boot, etc.


Hey, PCQ and anybody using any kind of battery extender, please run it at max screen brightness and almost max audio and any streaming video (streaming also using WiFi), and see how long can you run with your setup, a freshly topped N800 battery, please use genuine battery and specify your configuration, plus your battery extender/charger or what not, see how far can you go before your N800 quits. Mine, N800 battery + 2 AA 2000mAh = 2hr 15 min. I am disappointed.


bun

Re: External battery pack for N8x0/770.
 

bun, you're only disappointed? I'd think by now you would have been driven insane! :D

(Piin Cushion Queen -- this wraps up yet another sunny day, eh?)

Re: External battery pack for N8x0/770.
 

I got my answer, totally not acceptable.

I played the same N800 without "battery extender", just the N800 freshly topped battery, it ran 130 min straight till its knee and shut off. This compares to 135 min with battery extender. Horse5hit!!! So much for battery extender. It appears worked ONLY when the N800 battery is down to low critical, then my battery extender with 2 freshly charged 2000mAh is able to buy an additional hours, almost 50% of the native N800 battery. Not bad. It does no squat when the N800 battery is fresh and top. my next expt is to run at a very conservative measure and see how long it can run.


Edit: I was wrong about waking up the N800. My battery extender, 2 X AA 2000mAh freshly charged, seemed able to charge the N800, after waiting for 20 min, while the N800 battery charging cartoon is showing, it then waked up my N800, and has been running for an additional 20 min or so and still running, lets see how long it runs this time, and this is an internal flash boot, running on stressed conditions as quoted in previous post, almost mas audio, max brightness and WiFi streaming video.

Edit: 51 min. a set of freshly charged AA 2000mAh battery able to charge a dead N800 battery for 15 min and keep it running for another 51 min under a max/stressed conditions. Umm, maybe it is functional afterall.

Edit: 2X AA 1800 mAh also wakes up the N800 after 10 min of "charging" but runs only 2min under any conditions. Size matters ;)
bun

Re: External battery pack for N8x0/770.
 

Some time ago, I bought an Energizer brand charger that is made for cell phones. It takes two AA cells and has tips for different model phones, including Nokia. After all this discussion, I finally decided to try it out.

Running "mplayer -loop 0" with a ten minute Superman cartoon, the N800 battery alone ran for just two minutes shy of five hours (which amazed me greatly). For the last 40 minutes of that time, the N800 beeped at me every five minutes and said "low battery".

Doing the same test, but also with the Energizer supply plugged in to the N800, I got seven hours and nine minutes. This was using alkaline cells. The Energizer came with lithiums, which should give even better results. I didn't want to waste expensive lithiums on a test.

Both tests ran until the N800 shut down (sort of). With the Energizer plugged into the N800 power jack, the N800 tried to shut down, but kept rebooting. I finally hit the power button to shut it down. The N800 also did not give "low battery" warnings with the Energizer plugged in.

Not a huge difference, but for a power pack that you can hold in your palm, an extra 2+ hours isn't bad. What really surprised me was that the N800 battery alone lasted so long while playing video. I normally use the N800 for ebooks and occasional surfing and get 6-7 hours with those activities.

Re: External battery pack for N8x0/770.
 

I'll try it out this weekend - I use my precious much too much during the week to be able to live without it long enough to test this - I'm quite confident that I will see a lot more time than you are seeing. I'm thinking I'll get more like 12-15 hours.

I'm using 4 AA Sanyo 2700 mAh batteries in the Tekkeon 1550 with an official Nokia CA-100 cable - and the stock Nokia BP4L battery that came with my N810.

Re: External battery pack for N8x0/770.
 

Good post.

Mind to tell us how do you run the system? You max it out like what I did, almost max audio and max out brightness? MMC or internal flash boot? Presumably BT/WiFi off? Thanks,


bun

Re: External battery pack for N8x0/770.
 

I had the brightness set at exactly half, which is what I usually use. It seems plenty bright enough for me. The audio was 5 steps down from max. I didn't want to hear that Superman cartoon for several hours. I wouldn't think that the volume would have nearly as much impact on battery life as brightness.

I wasn't necessarily going for maxed out settings, as I wanted to see how long it would run with more typical settings.

Oh yeah, WiFi/BT off. Normal Flash boot.

Re: External battery pack for N8x0/770.
 

N800 Fuly Charged battery running without Tekkeon under the same conditions, how many hours?


bun

Re: External battery pack for N8x0/770.
 

Same question: what is the baseline, i.e., just running the tablet with the same conditions/setup but without any ext batt pack? Without that piece of information, the results are less useful.


bun

Re: External battery pack for N8x0/770.
 

just buyed this:
http://tinyurl.com/5s87au

seems to be very well done and 'versatile' :)

Re: External battery pack for N8x0/770.
 

This item is for powering device off but it works only if charger is not attached, otherwise it will just reboot. This is meant for situations when you (re)boot to boot menu and realize you wanted to turn device off instead.

What you expected it to do for you in this case? Also you say that you had attached power source (IOGear battery pack) when you selected this item and the device just powered off? It did not reboot immediately like it does with charger?

Re: External battery pack for N8x0/770.
 

what about this http://tinyurl.com/5olbh6 (about 5 euro) + 8 AA uniross hybrio (about 19 euro) and some diods to lower the voltage and save against the inversion recharge (many battery pack, if discharged, are recharged by the device you want to recharge !) ?
so:
2100*8=16800*1.2=20160/5.4 =about 3700mAh of capacity ?
seems not too difficult to made....

all for about 25euro.

sorry for bad english ;-)

Re: External battery pack for N8x0/770.
 

8 * 1.2V (assuming NiCd/NiMH voltage) is 9.6 V; that, one silicon (i.e. normal rectifier) diode, and a ~9 Ohm resistor of appropriate power rating should yield a workable power supply, which will fall inside the Nokia specifications (for I-V characteristic at least).

8 * 1.5V, OTOH, is 12 V; the maximum voltage permitted is 9.3V, so this would be outside the charger spec and potentially harmful to the device.

Edit: Oh, and your calculation is wrong; the capacity in Ah is the same as for one cell, since you connected them in series. You don't pick up any by reducing the voltage with passive elements; the extra energy dumps as heat, so make sure your resistor is rated for the resulting power. (9W, if I calculate right...)