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Subject: Fwd: Re: Dead JBM 20
From: Todd Wallace (
Date: 2004-08-19

------- Forwarded message -------
From: "Todd Wallace" <>
Subject: Re: Dead JBM 20
Date: Wed, 18 Aug 2004 18:19:22 -0400

Thanks for the information Markus.

As i have the unit completeley disassembled I tested the hd power input
pin and found only 4.2 volts. I then tested the battery and found 4.2
volts. I then plugged in the charger, which is putting out 5 volts and
tested the battery contacts and found 4.2 volts. I tested the contact on
the circuit board where the dc input comes in and found 5 volts although
on the other side of the circuit only 4.2. Is there a capacitor/diode that
steps down voltage? And does the unit need exactly 5 volts to power up?
For instance, as the battery runs down, aren't there fewer and fewer volts
available? I am wondering if it may be a power problem after all, bad
ground etc.

Once again, thanks so much for the assistance - Todd Wallace


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