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Re: HHB Portadisc

Subject: Re: HHB Portadisc
From: Marty Michener <>
Date: Thu, 04 Sep 2003 10:53:46 -0400
Dear Jeremy:

These suggestions are based on my four trips into tropical recording
conditions with the HHb.

All the posts I have read thus far keep referring to battery sets as though=

they were composed of units that behave as similarly as they
look.  Actually, I have been analyzing batteries since grad school in 1962,=

and typically have found one or two in any set of eight used in series that=

actually limit the overall performance, because the current flows through
all eight equally, despite the condition of each cell.

Here is a very simple test I strongly recommend doing:

Take a Portadisc caddy of 8 batteries fully charged, out of the unit.

Place a resistor across the snap connector on the end that will draw SOME
but not a lot of current, for example 470 ohm.
It will slowly get noticeably warm because 12 x 12 =3D 144, then divide by=

R=3D470 is about 0.3 watt.

I actually bought from Radio Shack some of those 9v battery snap
connectors, and soldered a 470 ohm half-watt resistor to the leads.  The
snap works with the end of the HHb battery caddy, so the test is easy to do=

whenever you want.

Under this load of about 25 milleamps, now user a voltmeter to CHECK EACH
BATTERY for its voltage.

Ideally you should get all of them to lie somewhere between 1.2 and 1.5
volts.  If one is much lower, replace it.  I would even swap them around to=

get each set to be as closely matched as possible.  If you have four sets
now, having three that are really matched would be better than four
unmatched.  Of my original FUJI set that came with the machine, here are my=


1.36  1.37  1.37  1.36  1.37  1.37  1.37  1.37

This set is labelled as 1.2 volts for 1550 mah.  So with this low drain in=

place, the resistor would last about 60 hours.

The results of this test are even more interesting when they are drained at=

the end of a session, because that is when one or more drop below their
rated 1.2 volts and may potentially become BACK CHARGED by the
others.  This will ruin a battery, and once it happens all bets about
matching the set are off.

My Radio Shack 1800 green set is nowhere nearly as good a match, even
though they have always been treated as a set, charged and discharged at
the same rates and times:

1.39  1.39  1.39  1.40 1.43 1.44 1.42 1.44

Regarding battery life in the field. I use the HHb on record-pause a lot,
because I am typically after one or two infrequently-calling species of
birds, so I walk as if I were recording (quitely, stealthily) much or most=

of my field time.  This drives birders nuts, because they always want to
talk about all the birds they see or hear.  Viva las Cryptophones.

My caddy life varies between about 2 and four real recording hours, and I
have only a rough idea how much of that time I spend
listening in the Record-pause mode (88%),
how much time in STOP (10%) and
how much time playing back what I just recorded (perhaps 2%)

Unlike Walt, I have seldom made one full disc by that time, due to the hold=

mode.  I too use the display light ON most of the time.

Despite the radio shack set variance, I get a bit more field recording time=

from that set, indicating that the 1800 vs 1550 may reflect a real capacity=

advantage.  I am always skeptical since the COPPER-TOP scam several years a=

The HHb percentage battery life is to me undecipherable in real use - the
numbers themselves are meaningless except on any one given day, you watch
the numbers whatever range they are, over, say, a period of fifteen minutes=

to one half hour.  When you get three consecutive significant drops (why do=

they sometimes RISE???) you turn the unit off for two minutes and that
writes the TOC onto the disc, then you turn it on and watch the battery
numbers very carefully to get ready to swap them for a new charged set.

For emergencies in the rain forest, I carry a set of 8 Photo Lithium
AA  L91 (expensive, light weight, not rechargable) in case both caddys are=

discharged and I am still in good or unusual bird sound environment.  In
Panama I had to rely on these, because the Cana field station only had 110=

v AC electricity for three hours every evening, and no charger I have does=

NiMH that quick.


With NiCd batterys there were numerous FAST chargers available, and I had
several battery sets that showed me (this was the 1960's) that the fast
charger actually kept the heavy duty batteries in better condition than the=

slow chargers.  Of course using NiCd s was a totally different world.

Question: What is the fasted way to charge all 8 NiMH AA batteries
completely, given that you often do not have "all night" to wait till you
need the recorder again?

Question: why don't we have a rechargeable Lithium ion setup for
recording?  For all my field computers, small MDs, palm pilots and video
machines bought in the last five years I typically get a "use it 4 hours,
recharge it in one hour" situation.  Why not HHb if it is really to be for=

professional use?  It is the only machine I own where the ration is
reversed - use it four hours, recharge twelve hours.  I know very few
professions that can work on that ratio of downtime.

good luck, Jeremy, my best to you.
Marty Michener
MIST Software Associates PO Box 269, Hollis, NH 03049  - Software that migrates with you.    http://www.EnjoyBirds=

At 06:59 PM 9/3/2003 -0300, you wrote:

>Thanks for the reply, Walter. Quick and detailed as always. My battery lif=
>is much lower than yours and I must now do some more careful testing to
>find where the problem lies.
> >There is a switch inside the Portadisc behind the battery caddy. It says
> >"Charge  OFF - ON". Set it to on and you should be able to charge the
> >batteries. That switch is in there in case you are using alkalines and
> >plug it in, so it won't try and charge alkalines and I know mine was
> >shipped with charge off. This info is in the owner's manual.
>The switch is on and the Portadisc appears to be charging. When I put the
>apparently charged batteries into the Portadisc it shows a full charge.
>However, this quickly drops. This happens even if I leave it charging all
>night after the green charge light is completely out.
> >You should probably verify the condition of your batteries. Maybe try a
> >new set. That's way, way too fast a battery usage. At that discharge
> >rate the batteries should be very hot to the touch. If they are not,
> >they do not have anywhere near 2200mAh in them. It's far more likely
> >that you have a problem with the batteries.
>I have four new sets of batteries from two different manufacturers and all
>give less than one hour of recording. I do use phantom power from the
>Portadisc, by the way.
>Thank you for finding out that I have an HHb distributor right on my
>doorstep but as a result of gruesome past experiences I would be extremely
>loath to entrust my precious recorder to a local repair shop. In Brazil
>they never have the skills nor the spares for specialised work. In the pas=
>I have twice had to pay to get my cassette recorder back from the repairer
>and then had to send it to the States. A friend of mine sent a microphone
>to Sennheiser's local people last month and they returned it still
>unusable. I'll check out SK Audio Professional Products but with
>considerable scepticism.
>I need my recorder for a long trip to Amazonia soon and will see how it
>goes. If the problems continue and are not the fault of the batteries I
>will almost certainly send the Portadisc for repair in the States.
>Thanks again for your help.


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