faq

编译后直接运行的ＭＰ３播放器全部Ｃ语言源代码 一个包含FAT文件系统、系统引导 Boot、FLASH Driver等内容的

     - Safely remove (Windows unmount device function) the Jukebox.
     Power it up and ...voila... Rockbox is there!

     (Thanks to Olivier Rafidison for this info)

     Another alternative:

     - Copy the firmware file to the jukebox again. Windows will rename it to "Copy of XXXXX"

     - Delete the original firmware file and remove the "Copy of" part from the new file name

     - Reboot

     If it doesn't load the correct firmware, do the whle procedure again until the new file is recognized.

Q65: What kind of mic can I connect to my AJBR?
A65: There are several types of microphones.

     Dynamic: The one that's available from Archos is a dynamic one.
     Their output level is high enough so that they don't need an
     amplifier (that's the reason why the Archos mic is of this type -
     it's cheap).
      - cheap
      - no good sound quality of cheap dynamic mics (good enough for
        speech)
      - no amplifier needed

     Backplate Condenser: These are the professional mics. They need phantom
     power (48V) for charging the condenser.
     They also need an amplifier, because their output level is low.
       - good sound quality
       - need phantom power (48V)
       - need amplifier
       - expensive              
 
     Electret Condenser: These capsules are cheap and result in a good
     recording quality. They don't need phantom power voltage. They need power
     for the FET (field effect transistor) that's inside. If you have such a
     mic with a battery in it, it is mostly because of the FET power, not
     because of an amplification circuit inside the mic.  These mics are in
     all the consumer products like mobile phones, PC headsets and so on.
       - cheap (2 EUR for a capsule)
       - good sound quality
       - need amplifier
       - need power for the FET (1,5 - 15V)

     Recommendation for do-it-yourselfers: Use electret condenser mic capsules,
     solder an amplifier for them which both amplifies the output level
     and feeds the power needed for the FET to the capsule.
     The one on http://www.geocities.com/ferocious_1999/md/micpreamp2.html
     was soldered and tested by Uwe Freese, and it works.
     There are some others available from www.elv.de and other sellers.

     Recommendation for others: Buy some mic + preamp combination which can be
     plugged into a line in of any amplifier. Maybe such a commercially
     available combination needs a power supply and doesn't work with
     batteries. Some are very expensive. (If you know a cheap solution with an
     electret condenser mic + preamp, please tell us!)

     What does not work: Don't use an amplifier thing that is simply connected
     between some mic cable. Maybe it sounds as if it could work, but I
     doesn't. If the piece of (expensive) electronic doesn't have a power
     source and your mic doesn't either, it does not work!  A PC sound card or
     md player usually has a power output (same pin where the sound goes
     through, dc value) for feeding the FET of an electret condenser capsule
     (see above) (and this power could also used to feed a mic amplifier), but
     the Archos hasn't (it's a line in and no mic in!).

     If you want to know more on microphone powering, read this:
     http://www.hut.fi/Misc/Electronics/circuits/microphone_powering.html.
     (As described, you also need amplification.)

Q66: I can't start rockbox when the charger is connected. What am I doing
     wrong?
A66: If your device is off and you connect the charger, the Archos charger code
     is started immediately. You can then start Rockbox with holding down the
     ON key for several seconds. Hold the key down a really long time, until
     you see the Rockbox logo!

Q67: Why can't you implement a cross-fader? That would be so cool!
A67: Please read our NODO faq. http://rockbox.haxx.se/docs/nodo.html#3

Q68: My screen is all black/white when I run Rockbox on my Recorder!
A68: We have no way of knowing the correct contrast setting from start and the
     displays differ a lot. Change your contrast setting by doing this:

     F1, down, right, down, down, right, down, down, down, right, down (until
     you like the contrast)

Q69: Where are the FM controls for the FM Recorder?
A69: In the menu: FM Radio

Q70: I installed/renamed ajbrec.ajz (or archos.mod) but I am still booting
     with another version of firmware.
A70: When looking on the hard disk the Archos firmware only matches the first
     ten characters of the file name.  Because of this files like 
     ajbrec.ajz.bak or ajbrec.ajz-20030404 match and are loaded.  To 
     prevent this from happening, give the it a file name that differs in 
     the first 10 characters, e.g., ajbrec.bak.ajz. 

Q71: Help! My recorder crashes when I copy files to it!
A71: Yes, the recorder can crash when you copy several gigabytes of
     files to it. The explanation is simple: Copying several gigabytes
     of files through USB requires a long period of sustained disk
     activity and drains more power than the batteries of the recorder
     can store. A long copy will eventually drain the batteries to the
     point where the recorder can no longer function and it halts.
     This even happens when connected to the charger, since the power
     drain is more than the charger can provide! If the recorder halts
     while connecter to the charger, the batteries will recover and
     after a short while it will reboot the Archos firmware in charger
     mode. To make it worse, depending on the USB drivers of your
     system it can cause your system to crash as well, or confuse it
     to the point it needs a reboot.

     There is no solution, just some tips:

     - Connect to the charger when copying lots of files. This will
     not prevent the problem, but it will take longer to happen.

     - Make sure you have "Deep Discharge" disabled.

     - Switch off the "Backlight On When Plugged" option.

     - Use USB 2.0. Transfers will be much faster.

     - Copy incrementally. With fully charged standard batteries it
     should be capable of sustained copying for 2 - 2.5 hours.

Q72: What should I know about digital I/O connector on my jukebox?
A72: The Recorder models have a connector for digital audio output using the
     common S/PDIF standard (Sony/Phillips Digital Interface). This jack is
     not present on the Studio/Player/FM Recorder models. By using the digital
     output in combination with high class external equipment, you can get
     much better sound quality out of your jukebox. This is because you can
     use better DA-converters and better amplifiers, plus you eliminate the
     analog audio connections between the jukebox and your equipment that can
     introduce noise and distortion.

     The Recorder and the FM Recorder models are able to record from digital
     sources, too. The digital inputs don't have the 15kHz lowpass filter like
     the analog inputs and you are sure to minimize the noise floor.

     Although S/PDIF can be an electrical or an optical signal and there are
     many devices that support both, the socket on the jukebox is for
     electrical signals only! Some devices have sockets that look the same,
     and can take either an optical or an electrical cable, but sadly this is
     not true with the Jukebox.

     If you want to connect your amp with digital input (RCA type) to the
     output of your Recorder you need an adapter cable (3.5mm stereo jack to
     dual RCA jack). Plug the 3.5mm stero jack into the digital I/O socket of
     your jukebox and the red RCA jack (right channel) into the digital input
     socket of your amp and that's it. You don't have to enable the digital
     output, since it's always on. The sound settings on the digital output
     are always flat, your volume, bass, treble, bass boost, loudness settings
     won't have any effect here, that's why fade in/out won't work,
     either. The sampling frequency of the digital output is the same as the
     sampling frequency of the mp3. It's therefore possible that your external
     equipment won't be able to synchronize to the output of your jukebox if
     you have mp3's with sampling frequencies other than 32, 44.1 or 48kHz
     (The pitch shift function also modifies the sampling frequency!).

     For recording digital signals on the Recorder, use the white RCA jack
     (left channel) and plug it into the digital output of your CD player, MD
     player or whatever. Don't forget to select digital input in the recording
     settings!

     Note that some adapter cables exist with different color coding, so if it
     doesn't work try to swap red and white. The tip of the 3.5mm jack is the
     digital input, the ring is the ouput. For recording digital signals on
     the FM Recorder, you need a special 4-pole 3.5mm plug (shaft = ground,
     tip = left channel analog line in, first ring (next to tip) = right
     channel analog line in, second ring = digital in).

     If you want to connect devices with optical inputs/outputs, you need a
     small converter box which converts your signal from electrical to optical
     (for digital output from the Archos) or optical to electrical (for
     digital recording in to the Archos).

Q73: How do I unsubscribe from the rockbox mailing list?
A73: The same way you subscribed, but you send an 'unsubscribe' request to the
     mailing list server instead of the 'subscribe' one you sent before.

     This is all mentioned on the same web page: http://rockbox.haxx.se/mail/

     Please please please pretty please with sugar on top, DO NOT attempt to
     mail unsubscribe requests to the mailing list itself. That will only
     annoy more than 400 readers and will have no effect on your subscription.

     In fact, you NEVER unsubscribe to ANY mailing lists by mailing unsubscribe
     to the list's address. You might as well take the opportunity to learn
     this right away.

     When you first subscribed to the mailing list, you were sent a welcome
     mail from the server. It contained information about the mailing list and
     instructions on how to unsubscribe. It is considered a good habit to keep
     such welcome messages from mailing lists.

     In addition to all this, every mail that is sent out to the rockbox
     mailing list has a set of standard headers that offer info about the
     mailing list: how to post, how to unsubscribe, where to find the mailing
     list archives etc. Sensible mail clients can display these headers.

Q74: What is the Recorder V2?
A74: The Recorder V2 is essentially an FM Recorder without the radio. It looks
     and works like the FM Recorder except for the radio, and has LiIon
     batteries. It is meant to replace the older Recorder model.
     NOTE! The first V2 Recorders were in fact real FM Recorders with the
     radio parts still mounted. If you are lucky, the FM radio might work in
     your V2, try it!

Q75: Why is there a Radio option in my Rockbox for V2?
A75: Some of the first V2 units had an FM radio in there, so if you're one of
     the few lucky ones, you can use the radio fine. If you aren't lucky, you
     just won't get any sound when trying the radio screen.

     UPDATE: The daily builds now auto-detect the FM radio hardware.

Q76: What does "dir buffer is full" mean?
A76: It means you have more files in a single directory than you have
     configured Rockbox to support. See Q53.

     Solution: Increase the "max files in dir browser" setting.