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Re: HHB Portadisc

Subject: Re: HHB Portadisc
From: Jeremy Minns <>
Date: Mon, 08 Sep 2003 14:46:25 -0300
Thanks to all the good advice I've received, I have established that my 
problems were probably caused by a battery fault. I have four sets of NiMH 
batteries, one of Fujitsu 1600 mAh cells which came with the recorder and 
three of Powerex 2200 mAh. With Sets 1, 3 and 4 the Portadisc records on my 
desk with phantom power for 3 or more hours. In the field I have been 
getting much less with Set 1, but this is probably because I often record 
short cuts and certainly because I have recently been experimenting with 
using the Portadisc for playback. I have not used Sets 3 and 4 yet in the 
field.

There seems to be something wrong with battery Set 2 (Powerex). I used it 
twice in the field and each time the recorder went dead after a short time. 
On bench tests, after charging the set on my MAHA MH-C777 charger and while 
recording with it in the Portadisc (with phantom power), the battery meter 
drops from 99% to 90% very quickly (after 6 mins in one test and 20 mins in 
a second). In the first test the recorder went dead after 13 minutes but in 
the second it lasted for 3 hours when the meter reached 60% and I stopped 
the test. Repeated charging and discharging seems to have improved the 
battery set's performance. I measured the voltage of the eight cells in Set 
2 (with a new multimeter; the old one was giving inaccurate readings which 
didn't help the investigation) while it was being discharged by the MAHA, 
before the second bench test. At the beginning of the discharge process the 
voltages were

1.32  1.32  1.32  1.32  1.32  1.29  1.31  1.30

and at the end

1.24  1.24  1.24  1.24  1.23  1.23  1.24  1.23

The cells seem well matched and possibly the fault has righted itself.

I was probably using the faulty Set 2 when I failed, several times, to 
charge in the Portadisc. I have now successfully used the Portadisc twice 
to charge Set 4 (Powerex). It's a long process and, as Walter said, one has 
to continue long after the green light goes out.

I can't tell you what a relief it is to be fairly confident that my 
Portadisc is probably not faulty! And I'm tremendously grateful to Walter, 
Marty, Rich, Klas and Martyn who have given me help and encouragement.

Jeremy





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