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Subject: RE: H340 : DC connector broken

RE: H340 : DC connector broken

From: Jammit Timmaj <>
Date: Tue, 16 Sep 2008 23:19:22 +0000

Subject: Re: H340 : DC connector broken
Date: Tue, 16 Sep 2008 18:53:30 +0200

Hi !

  ----- Original Message -----
  Also, the (-) of the charger shares the same ground as the screw holes,
  the metal frame of the USB jack, and is also grounded to the headphone common
  wire. With a continuity tester (available on pretty much any digital
  multi-meter) the wire of the DC jack that connects to all of those is the (-).
  One of the other DC connections would be (+). The third DC connection is
  probably connected to the (-) and can be found out with then
OK tnanks a lot, I will bring back my H340 to the
technician in my high school tomorrow. I'm sure he has such a
Just one more question : this technician already
soldered 2 out of the 3 points that could be soldered
to the DC jack inside of the iriver. He things he did it right for those two (le
+ to the + and the - to the -) but didn't know where to solder the third one.
If, when we chek this two wires with your method tomorrow, we confirm that the -
is linked to the -, can we try to connect my H340 to the DC charger ? In other
words, I don't understand why there are 3 points ? Is the third one unuseful ???
Will it damage my H340 if the first and the second one are correct but the third
one linked to nowhere ? (il fact, the piece of metal needed for the third one is
broken and he didn't find it inside of my h340)
The second method...

   Before you plug in the DC charger you may want to cut one of the
  wires and install a lightbulb of the same voltage rating of the charger. Just
  to make sure I'm understood about the lightbulb wiring, it'll be in series
  with the charging circuit. If the lightbulb comes on at full brightness that
  means the DC jack is wired backwards. Most semiconductors act like a forward
  biased diode when reverse polarity is applied. The lightbulb is not only an
  indicator but also as a current limiter to prevent a high reverse

sounds to me far more difficult. You wrote "may". If I
understood properly, if the first one works, we don't need the second one, do we
Thanks a lot

The three connections for the power jack are (+), (-), and (switch). On most devices with internal batteries that are supposed to be recharged while in the machine, the (switch) connection is normally not used and is normally connected to (-) or just left alone and soldered to a solder pad only to help stabilize the jack mechanically.

If the DC jack power connections are found correctly, you don't need to use the lightbulb trick. The lightbulb trick is only used if you're unsure if you've found the proper (+) and (-). If you have to use the lightbulb trick, find a lightbulb that doesn't need a lot of power. I apologize if I was a little confusing.

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Received on 2008-09-17

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