| Q1: Are my batteries charged all the time when connected to my Player/Recorder? |
| A1: Player: the charging is all done by hardware and the exact |
| functionality is hard to determine. It is however not recommended to keep |
| the charger connected for more than 10-15 hours if you're not using the |
| unit. |
| |
| Recorder: no. The charging algorithm is carefully crafted in to not wear |
| out the batteries any more than necessary. If you're using your unit |
| connected to the charger most of the time, use the 'deep discharge' option |
| to save your batteries somewhat. |
| |
| Q2: Will keeping my charger connected a long time damage my batteries? Can I |
| leave it over night? |
| A2: There's a deep discharge mode and you can switch trickle charge on and off. |
| If you use your AJB connected to the power supply the whole time, select |
| "deep discharge on" and "trickle charge off". If you want to charge your |
| AJB over night and take it with you the next day, select "deep discharge |
| off" (that it starts charging immediately) and "trickle charge on" |
| (that the batteries remain full). |
| |
| Trickle charge is needed to keep the batteries full. That's necessary because |
| the device will stay powered on and continue to consume some power from |
| the batteries (the hardware does not allow running from the charger |
| without charging batteries, or powering off with the charger connected). |
| The trickle charge time is 12 hours. It should be enough for you to disconnect |
| your AJB in this time and turn it off / use it. |
| However, after 12 hours of trickle charge, it will turn it off, the batteries |
| are discharged and another charge cycle is started. |
| |
| As the Battery FAQ at http://www.greenbatteries.com/ puts it: |
| "A NiMH battery can be charged and discharged hundreds of times, |
| but whether that means 200 times or 800 times has a lot to do |
| with how (you use it)". |
| |
| Q3: Does Rockbox charge the batteries more/less/worse/better than the Archos |
| firmware? |
| A3: Player: Rockbox doesn't affect the charging on Players, it is all done |
| by hardware logic out of software control. |
| |
| Recorder: The whole algorithm is made to carefully charge the batteries full |
| and keep them full after that with a trickle charge option. Many documents |
| about charge ICs were considered. If you want to know details, then look |
| into docs/CHARGING_ALGORITHM. If you have comments, write to |
| mail@uwe-freese.de or the Rockbox mailinglist. |
| |
| Test results with trickle charge (battery capacities measured with an |
| external charger, Model "Conrad Electronic Charge Manager 2010", ~100 EUR): |
| |
| - after normal charge and top off time: 1798, 1834, 1819, 1815 mAh |
| - after normal + top off + trickle charge (12h): 1784, 1748, 1738, 1752 mAh |
| - charged with external charger: 1786, 1819, 1802, 1802 mAh |
| |
| You can see, whenever you take your AJB with you in the 12h trickle charge |
| period, the batteries are at least 97% full. :) |
| |
| Q4: What kind of batteries are there in my factory default Player/Recorder? |
| A4: Both ship with 1500 mAh NiMH (Nickel Metal Hydride) batteries. |
| |
| Q5: Is it hard to change the batteries? Does it void my warranty? |
| A5: It is not very hard - the Archos manual and the FAQ on their web site |
| describe how to do it. Their technical support confirmed that |
| replacing the batteries with NiMH cells (of different capacities) |
| will not void the warranty. Just don't remove the screws. |
| |
| Some units have been shipped with two sets of batteries, my Recorder 20 |
| only had one set. Someone actually had Archos send him new batteries |
| free of charge after they had weared out, under the warranty. |
| |
| Q6: How much do replacement batteries cost? Where can I buy them? |
| A6: http://www.greenbatteries.com sells 1800 mAh NiMH cells at $3.25USD each, |
| and I bought 4 of the same GP batteries for 20 euros in an home |
| electronics & household appliance store in Finland. NiMH batteries are |
| sold in almost all shops that sell consumer electronics, and in many |
| online shops. Browse around. There's a pretty good comparison between |
| different battery makes and models at the digital imaging resource site: |
| http://www.imaging-resource.com/ACCS/BATTS/BATTS.HTM |
| In Germany, www.reichelt.de sells GP 2000 batteries for 2,75 EUR (12/2002). |
| |
| Q7: What kind of run-time can I expect on a set of fully-charged batteries |
| when running Rockbox? |
| A7: For the stock 1500 mAh cells, from 6 hours to 8 hours, depending on |
| which charger was used (see Q3). It depends a lot on the condition of the |
| batteries. With 2000 mAh batteries, you should reach about 10 hours or more. |
| We are looking into implementing more battery-saving techniques in rockbox |
| to make it rock longer. |
| |
| Q8: Can I use different batteries in my Archos? How much playtime would |
| I gain by using 1800 mAh batteries instead of the 1500 mAh ones? |
| A8: Only use NiMH-type rechargeable batteries. It is considered to be safe |
| to use NiMH batteries of different capacities though, a lot of people |
| have purchaced 1700 or 1800 mAh batteries to replace the stock 1500 mAh |
| cells and have the device run a bit longer. 2000 mAh batteries are |
| just appearing in shops are equally good to use. |
| |
| In theory, running time = capacity of batteries / current drawn by device, |
| so running time should increase linearly by the capacity, and 2000 mAh |
| over 1500 mAh should give 33% longer running time. In practice, the |
| mAh ratings are more or less tuned up by the marketing department |
| (think of watts on the back of "hi-fi" speakers and amplifiers) and |
| what you actually get out of the cells is something else than what is |
| printed on them. Check the excellent imaging-resource link above for |
| details! |
| |
| Q9: Can I use non-chargeable batteries in my Archos? |
| A9: This is not recommended. The unit has been designed to operate with |
| four 1.2V batteries producing about 4.8V at most, and using 1.5V |
| alkaline/zinc carbon batteries will produce around 6.0V, which will |
| heat up the unit a lot more and might even damage it. The Archos |
| manual explicitly tells you not to do so. |
| Also, if you connect the charger, it may even destroy both the batteries |
| and the unit. |
| |
| Q10: Can I use a different charger? |
| A10: The short answer is: Using a different charger will void your warranty |
| and can be dangerous to your unit, so we can not recommend it. |
| |
| On the other hand, people have successfully used different chargers |
| with similar specifications as the stock charger. The charger must |
| have the same kind of connector with same polarity (center positive/+). |
| The charger should supply at least 7-8 volts, and if it provides |
| more than 10V, it probably should be regulated to 10V (do not |
| directly plug it in your 12V car battery or it's charger!). |
| The universal travel charger sold by Archos is specified at |
| 12V, 1.2A so that's probably the maximum rating you should use. |
| A good circuit for powering from a car battery or other source |
| with a higher voltage would be a 600 mA fuse and a 10V regulator like |
| a 7810 of your favourite manufacturer in series. |
| |
| Inside the Jukebox there is a regulator which limits the charging |
| current applied to the batteries. The higher the input voltage, the hotter |
| this IC gets. Don't use an input voltage above 12V. |
| Using lower charging voltage < 10V will slow down the charging. But the |
| rockbox charging algorithm should work then, too. |
| |
| These are the output voltages of an original archos power supply: |
| - connected to AJB Recorder, not charging: 13,7 Volt |
| - connected to AJB Recorder, charging: going down to 10,4 Volt |
| |
| Here is how changing the input voltage changes the charging current: |
| |
| voltage charging current (limited only by the AJB) |
| ------------------------------------------------------ |
| 7,0V 10 mA |
| 7,5V 30 mA |
| 8,0V 50 mA |
| 8,5V 70 mA |
| 9,0V 140 mA |
| 9,5V 250 mA |
| 10,0V 330 mA |
| 10,5V 350 mA |
| 11,0V 350 mA |
| 11,5V 350 mA |
| 12,0V 350 mA |
| |
| To summarize: |
| |
| - do not use an input voltage > 12V (it will only heat up the regulator) |
| - optimal input voltage is 10V (regulated) |
| - use a fuse of ~600mA |
| - using a different charger voids your warrenty |
| |
| Many people are happy using an external quick charger which |
| is specified to work with NiMH batteries. This is completely safe |
| and will not void your warranty. |
| |
| Q11: Can I buy a replacement charger exactly as the one Archos shipped? |
| A11: The FAQ on the Archos web site and the top of the charger both read: |
| |
| Output: 9VDC 600mA |
| Center positive (+) polarity |
| |
| The universal travel charger sold separately on the Archos web site |
| is specified for 12VDC, 1200mA output. |
| |
| Chargers with similar (or user-adjustable) properties are available |
| at shops selling consumer electronics. |
| |
| Q12: I often need to stop my player for about 15 minutes or so, and when I do |
| it runs off it's batteries. I was wondering, which is best: shutting the |
| player down completely and rebooting it when I want to listen again, or |
| leaving the unit on? Which way does it draw more power? |
| A12: In our testing we found the following results: |
| HDD off, backlight off, idle 94 mA |
| HDD off, backlight off, play 97 mA |
| HDD off, backlight on, idle 129 mA |
| HDD off, backlight on, play 131 mA |
| HDD on, backlight on, play 230 mA |
| HD on, reading, backlight off ~ 600 mA |
| HD spin up before read max 800 mA |
| |
| So leaving the unit on and paused consumes ~100mA, and thus much less |
| than needing to reboot the unit. Your mileage may vary. |
| |
| Q13: When I plug in the charger when the Recorder is turned off, it turns |
| itself on and starts charging in the Archos software? What's up? |
| A13: There is a switch in the DC IN jack of the Jukebox - when a charger (or |
| whatever) is plugged in, the unit is powered on, even if the charger |
| is not plugged in a mains outlet. |
| |
| If the charger is providing power at this point, the Archos firmware |
| located on the FLASH ROM does not load a new firmware version (like |
| Rockbox) from the disk, but goes into charging mode instead. You can |
| use this feature to get to the Archos charger if you want to. |
| |
| Q14: When I plug the charger in my Recorder, it doesn't immediately start |
| charging the batteries! |
| A14: When Rockbox is running on the Recorder (the device has been booted |
| without the charger) it's power management code runs once per minute |
| (thus the charge level and charging status is only updated every minute). |
| If the battery is not full, it will start charging. If the 'deep |
| discharge' mode is enabled in the settings menu, it will start charging |
| only when the battery is almost empty. |
| |
| Q15: What about the memory effect? Should I be worried about it or not? |
| A15: That depends on who you ask. ;-) NiMH sellers say NiMHs are better and |
| do not have a memory effect, but the usual opinion seems to be that |
| they do, although it is very small. |
| |
| However, if you use your AJB connected to the charger all the time, |
| we recommend you to use the deep discharge option. |