there was thread here about battery life, and some of the new technology
wrt digital cameras (eating AA Alkalines). i got suckered into buying
another camera, and guess what, it really EATS AA'a, changing batteries
would be a full time job.

the previous owner said he used 1600mah NMiH rechargeables and got
50-60 shots, some w/flash, some without the lcd on, but was generally
happy.

Question: before i even think about buying into an expensive set up
for only occaisional use, i need to know what is the actual capacity of
the current crop of AA Alkaline battery. googling now, but find nothing
beyond suggested uses on manufacturers sites.

Thanks! --Loren

Loren,

AA alkalines are higher capacity than the rechargeables,
but they are best utilized at slower rates of discharge.
Cameras are high rate-of-discharge applications and that's
why alkaline AAs don't deliver the performance you'd
normally expect.

Your friend was correct in recommending NiMH rechargeables,
you can get a decent set of 4 and a charger for about
$10 if you look for sales. Never need to pay more than
about $15.

We can discuss it further when we get together regarding
the guns, I've used NiMH and high-capacity NiCads in
many applications over the years.

Martin


lcoe wrote in message news:%rVOa.17979$ye4.16543@sccrnsc01...
there was thread here about battery life, and some of the new technology
wrt digital cameras (eating AA Alkalines). i got suckered into buying
another camera, and guess what, it really EATS AA'a, changing batteries
would be a full time job.

the previous owner said he used 1600mah NMiH rechargeables and got
50-60 shots, some w/flash, some without the lcd on, but was generally
happy.

Question: before i even think about buying into an expensive set up
for only occaisional use, i need to know what is the actual capacity of
the current crop of AA Alkaline battery. googling now, but find nothing
beyond suggested uses on manufacturers sites.

Thanks! --Loren

Your friend was correct in recommending NiMH rechargeables,
you can get a decent set of 4 and a charger for about
$10 if you look for sales. Never need to pay more than
about $15.

Please don't do that! Those cheap chargers are either constant current
or timer terminated. Pay somewhat more and you can charge your
batteries whenever you feel like it without worrying about state of
charge. Ray-o-vac has a good charger but, personally, I like the Maha
line. My 204 isn't as versatile as some of the newer ones but it works
well. I paid Cdn$30 for it a couple years ago.
For example, see
http://www.thomas-distributing.com/batteries.htm

Ted

On Wed, 09 Jul 2003 21:04:18 GMT, Ted Edwards wrote:

Your friend was correct in recommending NiMH rechargeables,
you can get a decent set of 4 and a charger for about
$10 if you look for sales. Never need to pay more than
about $15.

Please don't do that! Those cheap chargers are either constant current
or timer terminated. Pay somewhat more and you can charge your
batteries whenever you feel like it without worrying about state of
charge. Ray-o-vac has a good charger but, personally, I like the Maha
line. My 204 isn't as versatile as some of the newer ones but it works
well. I paid Cdn$30 for it a couple years ago.
For example, see
http://www.thomas-distributing.com/batteries.htm

Ted

Greetings Ted and Icoe,
What Ted Says! When I bought my digital camera I researched it (with
lots of help from RCM) and the gist of the battery life question was
to get the 1800 mah nimh batteries, made by MAHA, from Thomas
Distributing. They lasted longer that alkaline batteries in digital
cameras. And they can be thrown in the charger any time. When the
batteries get about halfway down I exchange 'em. Keeps plenty o charge
in the camera. And battery life is great. much better than the manual
said to expect with alkalines. Thomas Distributing has a battery and
charger deal. I just got four batteries as my camera uses two. Works
great.
Cheers,
Eric R Snow

On Wed, 09 Jul 2003 21:04:18 GMT, Ted Edwards wrote:

Your friend was correct in recommending NiMH rechargeables,
you can get a decent set of 4 and a charger for about
$10 if you look for sales. Never need to pay more than
about $15.

Please don't do that! Those cheap chargers are either constant current
or timer terminated. Pay somewhat more and you can charge your
batteries whenever you feel like it without worrying about state of
charge. Ray-o-vac has a good charger but, personally, I like the Maha
line. My 204 isn't as versatile as some of the newer ones but it works
well. I paid Cdn$30 for it a couple years ago.
For example, see
http://www.thomas-distributing.com/batteries.htm

Ted

Cannot beat the New Discovery IQ9000 universal charger for AAs, Nicad,
NiMH, or alkaline. It uses a CEC1100 Microprocessor. 200:1 negative
pulse charge technology. 900ma charge current

Dave Martindale wrote:
lcoe writes:

Question: before i even think about buying into an expensive set up
for only occaisional use, i need to know what is the actual capacity of
the current crop of AA Alkaline battery. googling now, but find nothing
beyond suggested uses on manufacturers sites.

That's not likely to be a useful piece of information to you. Battery
manufacturer's data sheets show AA alkaline capacity as something like
2800 mAh last time I looked, but that capacity is achieved only with
very low discharge current (e.g. something like an electronic clock).
[......]
Now, digital cameras can draw several amps when powering the CCD, the
LCD and its backlight, and recharging the flash. (For example, the AC
adapter for my Canon G2 is rated for 2.7 A output). Under these loads,
an alkaline battery may indeed have a useful capacity of only a few
minutes of operation. That's why they're pretty useless in digicams.

Dave, thanks for spelling this out so clearly, and thanks to everyone
else who offered advice/experience. i believe i am _finally_ getting
the message.

NiCd, NiMH, and LiIon cells all have lower internal resistance, and can
deliver currents of several amps without much reduction in capacity from
their low-rate ratings. So all of them are better suited to powering
digicams. If your camera takes AAs, NiMH cells are the best choice
for inexpensive operation. If you need a single-use battery that still
provides a reasonable number of shots, use single-use lithium AA. Dave

my thought early today, after reading Sphero's post, was that i just kludge
some kind of battery pack, may still do that (it worked very well on my
Tandy 100) but for now, "get up to date, DUDE!". Usenet, loveit, rcm,
sci.electronics.repair are two reasons why. --Loren

In article %rVOa.17979$ye4.16543@sccrnsc01,
lcoe wrote:

there was thread here about battery life, and some of the new technology
wrt digital cameras (eating AA Alkalines). i got suckered into buying
another camera, and guess what, it really EATS AA'a, changing batteries
would be a full time job.

the previous owner said he used 1600mah NMiH rechargeables and got
50-60 shots, some w/flash, some without the lcd on, but was generally
happy.

Question: before i even think about buying into an expensive set up
for only occaisional use, i need to know what is the actual capacity of
the current crop of AA Alkaline battery. googling now, but find nothing
beyond suggested uses on manufacturers sites.

Thanks! --Loren


Why don't you also run this by the folks over at:

sci.chem.electrochem.battery

I look around over there once in a while for the hell of it... they seem
to have some sharp people with good practical thoughts...

Good Luck!

Erik

Ted Edwards wrote in message ...
Your friend was correct in recommending NiMH rechargeables,
you can get a decent set of 4 and a charger for about
$10 if you look for sales. Never need to pay more than
about $15.

Please don't do that! Those cheap chargers are either constant current
or timer terminated. Pay somewhat more and you can charge your
batteries whenever you feel like it without worrying about state of
charge. Ray-o-vac has a good charger but, personally, I like the Maha
line. My 204 isn't as versatile as some of the newer ones but it works
well. I paid Cdn$30 for it a couple years ago.
For example, see
http://www.thomas-distributing.com/batteries.htm
Ted

Ted,

That's partly correct. Yes, the cheap chargers are constant-
current, but no, they are not a problem. For most NiMH cells,
the "cheap" chargers are charging at a rate less than C/10, and
are no problem even if left plugged in all day. I bought my
sets from bydusa online over a year ago, and all cells are
still going strong. I paid $7.49 for the charger PLUS four
1800 mAH cells. Bought two sets, keep one charger at home and
the other in my camera bag with fresh cells in it. Makes a
good "battery holder".

Only if you want a "fast charger" do you need to step up to the
more expensive setup with microprocessor, and yes, you can get a
great one for less than $15. For 22.95 you can have the charger
and EIGHT NiMH cells (four AA and four AAA, I use the AAA in FRS
walkie-talkies). Model V-1000 package:

http://www.batteryspace.com

This thing works great, and it's dual-power, either AC or an
included cigarette-lighter adapter. I've also used it for
over a year. I keep this one in the console of my truck for
when I need to quick-charge cells, as it's not as small as the
slow charger that I keep in the camera bag.

best regards,

Martin

(Remove SPAM From Address to Reply) writes:

Please don't do that! Those cheap chargers are either constant current
or timer terminated.

That's partly correct. Yes, the cheap chargers are constant-
current, but no, they are not a problem. For most NiMH cells,
the "cheap" chargers are charging at a rate less than C/10, and
are no problem even if left plugged in all day.

There are two different types of cheap charger. They're both constant
current with no detection of end of charge. One type uses a low enough
charge rate that a full charge takes 14 hours; that's what you're
talking about. If the batteries start out partially charged, not
completely discharged, they will be overcharged - but at such a low
current that it won't hurt them.

However, the *timed* cheap chargers use a higher current that will
recharge the batteries in about 5 hours. They are a problem because
they will properly recharge *only* a specific capacity of battery, and
*only* if it's fully discharged before charging. If the battery is
higher capacity than the charger is designed for, the timer will shut
off before full charge is reached. If the battery is the correct
capacity but isn't fully discharged, then the charger will overcharge
it, and with a current large enough to damage the battery.

So, avoid the timed chargers completely. 14-hour chargers are OK but
slow. Fast chargers with end-of-charge detection are OK and fast.

Dave

Dave Martindale wrote:

There are two different types of cheap charger. They're both constant
current with no detection of end of charge. One type uses a low enough
charge rate that a full charge takes 14 hours; that's what you're
talking about. If the batteries start out partially charged, not
completely discharged, they will be overcharged - but at such a low
current that it won't hurt them.

From my reading, this seems to be somewhat cotroversial, some authors
and manufacturers claiming C/10, some C/20 and some saying even lower.
My MAHA 204 charges at C/60 after the end of the fast charge cycle.

It's probably on sacle of decreasing badness. :-)

Ted

writes:

From my reading, this seems to be somewhat cotroversial, some authors
and manufacturers claiming C/10, some C/20 and some saying even lower.
My MAHA 204 charges at C/60 after the end of the fast charge cycle.

It's probably on sacle of decreasing badness. :-)

Yes, in the same way that leaving the batteries in a slow charger for 24
hours is worse than removing them after 14, but better than leaving them
for 48.

I never use anything but fast chargers now myself. But slow chargers
are better for the batteries than timed chargers, and so it's useful to
distinguish between them.

Dave

I picked up (at a local auction) a set of six Eveready Nimh AA's, two AAA's,
a charger, two AA-to-C adaptors and two AA-to-D adaptors, all new in
unopened package the other day.

The price? $10.00.

jak

"Cher" wrote in message
...
you can find NMH batteries with 1600 to 1900 MaH capacity on the web
for about $1 each in quantity of 24 or more.

regular alkaline batteries in a digital camera are useless.



On Wed, 09 Jul 2003 14:15:23 GMT, lcoe
wrote:


there was thread here about battery life, and some of the new technology
wrt digital cameras (eating AA Alkalines). i got suckered into buying
another camera, and guess what, it really EATS AA'a, changing batteries
would be a full time job.

the previous owner said he used 1600mah NMiH rechargeables and got
50-60 shots, some w/flash, some without the lcd on, but was generally
happy.

Question: before i even think about buying into an expensive set up
for only occaisional use, i need to know what is the actual capacity of
the current crop of AA Alkaline battery. googling now, but find nothing
beyond suggested uses on manufacturers sites.

Thanks! --Loren

Oops...spoke too soon--they are Panasonic brand Nimh's.

jak

"jakdedert" wrote in message
...
I picked up (at a local auction) a set of six Eveready Nimh AA's, two
AAA's,
a charger, two AA-to-C adaptors and two AA-to-D adaptors, all new in
unopened package the other day.

The price? $10.00.

jak

"Cher" wrote in message
...
you can find NMH batteries with 1600 to 1900 MaH capacity on the web
for about $1 each in quantity of 24 or more.

regular alkaline batteries in a digital camera are useless.



On Wed, 09 Jul 2003 14:15:23 GMT, lcoe
wrote:


there was thread here about battery life, and some of the new
technology
wrt digital cameras (eating AA Alkalines). i got suckered into buying
another camera, and guess what, it really EATS AA'a, changing batteries
would be a full time job.

the previous owner said he used 1600mah NMiH rechargeables and got
50-60 shots, some w/flash, some without the lcd on, but was generally
happy.

Question: before i even think about buying into an expensive set up
for only occaisional use, i need to know what is the actual capacity of
the current crop of AA Alkaline battery. googling now, but find
nothing
beyond suggested uses on manufacturers sites.

Thanks! --Loren

Dave Martindale wrote:

I never use anything but fast chargers now myself. But slow chargers
are better for the batteries than timed chargers, and so it's useful to
distinguish between them.

Agreed but a smart charger is so inexpensive considering how many safe
effective recharges you will get, not to mention the convenience.

Ted

Icoe:
Yes, actually.... the Radio Shack #23-405 is only for NiCad and NiMH....
NOT for LITHIUM.
and, yes, it is microprocessor controlled and is designed to specifically
sense the unique charging curves of NiCad or NiMH, switch selectable and
will shut off when it achieves full charge as detected by the chip...... or
failing that, it's backup timer will shut it off.
It is a nicely built unit and if used properly should work just fine....
the business about charging only fully discharged cells applies mainly to
NiCad .... by fully discharging them, the "memory effect" is negated. You
really do not want to fully discharge NiMH every time you charge them....
and you don't have to.... there is no memory effect to worry about.....
--
Best Regards,
Daniel Sofie
Electronics Supply & Repair
--------------------------------------------


"lcoe" wrote in message
news:nzxPa.34650$ye4.26674@sccrnsc01...

Ted, or anyone, i bot a RShack "Auto Sensing" model (for ni-cad and
lithium).
the manual and box says, "automatically senses full charge and shuts off".
further, in the manual it says, '`...charge only fully discharged
cells...'

another feature is a "backup" fixed timer, 1.5hr for nicad, 2.0 for lith.
it's RS model 23-405, 50% off recently. it's heavy, brick shaped, but
is it really fully automatic? Thanks! --Loren

In rec.crafts.metalworking Sofie wrote:
Icoe:
Yes, actually.... the Radio Shack #23-405 is only for NiCad and NiMH....
NOT for LITHIUM.

yes, i mis-spoke, thanks for noticing.

and, yes, it is microprocessor controlled and is designed to specifically
sense the unique charging curves of NiCad or NiMH, switch selectable and
will shut off when it achieves full charge as detected by the chip...... or
failing that, it's backup timer will shut it off.
It is a nicely built unit and if used properly should work just fine....
the business about charging only fully discharged cells applies mainly to
NiCad .... by fully discharging them, the "memory effect" is negated. You
really do not want to fully discharge NiMH every time you charge them....
and you don't have to.... there is no memory effect to worry about.....
-- Best Regards, Daniel Sofie Electronics Supply & Repair

do you, or anyone know the cutoff voltage for the charge cycle? was thinking
of testing it by charging some partially discharged alkalines.

i see some newer chargers on-line that have a switch selectable "dis-charge"
then/charge mode. i believe it works for either type battery. Thanks! --Loren
`
--------------------------------------------


"lcoe" wrote in message
news:nzxPa.34650$ye4.26674@sccrnsc01...

Ted, or anyone, i bot a RShack "Auto Sensing" model (for ni-cad and
lithium).
the manual and box says, "automatically senses full charge and shuts off".
further, in the manual it says, '`...charge only fully discharged
cells...'

another feature is a "backup" fixed timer, 1.5hr for nicad, 2.0 for lith.
it's RS model 23-405, 50% off recently. it's heavy, brick shaped, but
is it really fully automatic? Thanks! --Loren

Icoe:
I would very strongly suggest that you NOT put alkaline batteries in your
Radio Shack #23-405 charger..... it is only designed for NiCads and NiMH.
DO NOT put alkalines in ANY charger not specifically designed for
alkalines..... they may explode or at the very least, get hot and make a
hell of a mess.
The cut-off voltage and charging curve is different for NiCad versus NiMH
..... that is why the charger has a 2 position selection switch..... make
certain it is set correctly for the type of battery you are charging....
notice that there is NOT a 3rd selection position for Alkaline...... do NOT
attempt to recharge alkaline batteries in this charger.
The automatic discharge and then recharge feature of some chargers and
reconditioners was meant mainly for NiCads..... to help minimize the "memory
effect" ...... not really needed for NiMH although there are those that say
it helps and others that say that regular deep cycling of NiMH is not
beneficial or even good for the battery..... my experience suggests the
latter.
--
Best Regards,
Daniel Sofie
Electronics Supply & Repair
--------------------



"lcoe" wrote in message
news:J1BPa.36050$H17.10762@sccrnsc02...

do you, or anyone know the cutoff voltage for the charge cycle? was
thinking
of testing it by charging some partially discharged alkalines.

i see some newer chargers on-line that have a switch selectable
"dis-charge"
then/charge mode. i believe it works for either type battery.
Thanks! --Loren
`

lcoe wrote:

Ted, or anyone, i bot a RShack "Auto Sensing" model (for ni-cad and lithium).
the manual and box says, "automatically senses full charge and shuts off".
further, in the manual it says, '`...charge only fully discharged cells...'

That's a bad sign. A smart charger should be detecting end of charge by
watching for delta-V (a slight drop in voltage). I am concerned that
they say NiCd and lithium (what lithium?) but do not mention NiMH.

another feature is a "backup" fixed timer, 1.5hr for nicad, 2.0 for lith.
it's RS model 23-405, 50% off recently. it's heavy, brick shaped, but
is it really fully automatic?

Personally, I would not go for it. Sounds wrong.

Ted

lcoe writes:

do you, or anyone know the cutoff voltage for the charge cycle? was thinking
of testing it by charging some partially discharged alkalines.

There isn't a "cutoff voltage". NiMH and NiCd cells are charged while
monitoring voltage over time. As the cells reach full charge, the
terminal voltage rate of change goes to zero, and then negative (i.e.
the voltage *drops*). This is what the chargers sense. They may also
sense the rapid rise in temperature at end of charge.

Don't put alkalines in this charger. Alkalines won't accept high charge
currents, and they'll probably burst or leak.

Dave

lcoe writes:

so i popped them in and the camera fired up fine, and i reviewed pictures
taken w/these same batteries. then i went to 'record', it tried, but
shutdown. again, sameo, sameo.

This is really just demonstrating that alkalines aren't suitable for
your digital camera - too much internal resistance.

Rechargeable alkalines, even on their first use, are worse than
single-use ones, Later discharges get worse yet because internal
resistance increases. I don't expect single-use alkalines that have
been recharged are any different in this respect.

the choice still remains to install fresh alkalines, assuming the
balance of the battery cap. could be utilized, and if i am willing
to put up with the intemittant operation of the camera. for now,
it's going to be Ni-mh, but i will not be able to resist further
testing.

Forget the alkalines. You've demonstrated that they're useless except
as an absolute last resort. Use NiMH for day to day use. Buy a set of
single-use lithium AAs for backup if you can't always be sure of having
enough NiMH batteries for a trip.

Dave

Right on the money. Heat kills batteries. Cheap chargers overheat the
batteries. The Maha chargers work nice for reasonable cost. I have NiMH
batteries that still work well after 5 years thanks to the TLC they get in
my cheapie Maha charger. Thomas Distributing is the place to get 'em.

Speaking of heat, you should use caution in using lithium AA throwaway
batteries. They apparently get quite hot during heavy discharge cycles. So
much so that my Olympus D-600L's warranty would be voided if those batteries
were used in it.

Ted Edwards wrote in message ...

Please don't do that! Those cheap chargers are either constant current
or timer terminated. Pay somewhat more and you can charge your
batteries whenever you feel like it without worrying about state of
charge. Ray-o-vac has a good charger but, personally, I like the Maha
line. My 204 isn't as versatile as some of the newer ones but it works
well. I paid Cdn$30 for it a couple years ago.
For example, see
http://www.thomas-distributing.com/batteries.htm

Ted

On Fri, 11 Jul 2003 19:34:24 +0000 (UTC), (Dave
Martindale) wrote something
.......and in reply I say!:

PMFJI. You sound as if you are addressing the questions I have.

I have a couple of little Uniden walkie-talkies, that take 4 X AAA
cells. They chew out the cells fairly fast, so I bought NiCds. No go.
The radios appear to have trouble dealing with the lower voltage. I
reckon they are trying to grab max volts to get Tx power up, and
probably should have had an extra battery. Rechargeable ALkalines
worked fine, but as you say deteroriate rapidly.

Sorry. Question. Are NiMH cells better in this regard? I am ringing
battery houses, and one guy said they were. I assume this would be
because they have lower internal resistance. Is this so? I got the
impression the guy knew more about _batteries_ than I do, but less
about electrical theory G

Next G. One shop had several AH capacities, at different prices
(actually they were the only ones to explain this, and will get my
custom). Are there any advantages/disadvantages to getting the lower
capacities, if this means they get discharged better etc?

Thanks for any help. Sick of buying expensive "special" chargers that
then gather dust.

This is really just demonstrating that alkalines aren't suitable for
your digital camera - too much internal resistance.


************************************************** ****************************************
Huh! Old age!. You may hate it, but let me tell you, you can't get by for long without it!

Nick White --- HEAD:Hertz Music
Please remove ns from my header address to reply via email
!!
")
_/ )
( )
_//- \__/

(Old Nick) writes:

I have a couple of little Uniden walkie-talkies, that take 4 X AAA
cells. They chew out the cells fairly fast, so I bought NiCds. No go.
The radios appear to have trouble dealing with the lower voltage. I
reckon they are trying to grab max volts to get Tx power up, and
probably should have had an extra battery. Rechargeable ALkalines
worked fine, but as you say deteroriate rapidly.

Sounds like the radio is poorly designed. Alkaline cells start at 1.5
volts, but drop pretty much continuously in voltage as they are drained.
Depending on the load, a device needs to operate properly down to 1 V
per cell (light load) to 0.8 V per cell (heavy load) in order to get
most of the energy out of alkalines. So a properly-designed radio
powered by 4 alkaline cells should tolerate 6 V in, but work properly
all the way down to 4 V. NiCd and NiMH cells provide about 1.2 V over
nearly their entire discharge time, over a wide range of load. Thus,
4 cells will provide 4.8 V and the radio *should* work fine.

If the radio doesn't work on NiCds, and the NiCds were in fact all good,
then it just doesn't operate properly at 4.8 V. If it works at 6 V but
not at 4.8 V, it will start working OK on alkalines, but stop working
when the alkalines are still half-full.

Sorry. Question. Are NiMH cells better in this regard? I am ringing
battery houses, and one guy said they were. I assume this would be
because they have lower internal resistance. Is this so? I got the
impression the guy knew more about _batteries_ than I do, but less
about electrical theory G

NiMH is not better than NiCd in this respect. NiMH actually have higher
internal resistance than NiCd, though still far below alkalines. If
NiCds don't work, NiMH aren't likely to either.

Next G. One shop had several AH capacities, at different prices
(actually they were the only ones to explain this, and will get my
custom). Are there any advantages/disadvantages to getting the lower
capacities, if this means they get discharged better etc?

Lower capacity cells may just be older. But they may also have lower
internal resistance. You can't really tell without measuring. I
wouldn't pay much of a premium for exceptionally high capacity.

Dave

All the Motorola FRS radios (that I'm familiar with) use three AA cells.
All of their literature states that alkalines or Nimhs *must* be used.
According to Motorola, NiCads are not acceptable.

jak

"Dave Martindale" wrote in message
...
(Old Nick) writes:

I have a couple of little Uniden walkie-talkies, that take 4 X AAA
cells. They chew out the cells fairly fast, so I bought NiCds. No go.
The radios appear to have trouble dealing with the lower voltage. I
reckon they are trying to grab max volts to get Tx power up, and
probably should have had an extra battery. Rechargeable ALkalines
worked fine, but as you say deteroriate rapidly.

Sounds like the radio is poorly designed. Alkaline cells start at 1.5
volts, but drop pretty much continuously in voltage as they are drained.
Depending on the load, a device needs to operate properly down to 1 V
per cell (light load) to 0.8 V per cell (heavy load) in order to get
most of the energy out of alkalines. So a properly-designed radio
powered by 4 alkaline cells should tolerate 6 V in, but work properly
all the way down to 4 V. NiCd and NiMH cells provide about 1.2 V over
nearly their entire discharge time, over a wide range of load. Thus,
4 cells will provide 4.8 V and the radio *should* work fine.

If the radio doesn't work on NiCds, and the NiCds were in fact all good,
then it just doesn't operate properly at 4.8 V. If it works at 6 V but
not at 4.8 V, it will start working OK on alkalines, but stop working
when the alkalines are still half-full.

Sorry. Question. Are NiMH cells better in this regard? I am ringing
battery houses, and one guy said they were. I assume this would be
because they have lower internal resistance. Is this so? I got the
impression the guy knew more about _batteries_ than I do, but less
about electrical theory G

NiMH is not better than NiCd in this respect. NiMH actually have higher
internal resistance than NiCd, though still far below alkalines. If
NiCds don't work, NiMH aren't likely to either.

Next G. One shop had several AH capacities, at different prices
(actually they were the only ones to explain this, and will get my
custom). Are there any advantages/disadvantages to getting the lower
capacities, if this means they get discharged better etc?

Lower capacity cells may just be older. But they may also have lower
internal resistance. You can't really tell without measuring. I
wouldn't pay much of a premium for exceptionally high capacity.

Dave

"jakdedert" writes:
All the Motorola FRS radios (that I'm familiar with) use three AA cells.
All of their literature states that alkalines or Nimhs *must* be used.
According to Motorola, NiCads are not acceptable.

That's not true of the T6210. In the battery installation section, it
just says "AA batteries" or a special NiMH pack sold by Motorola. It
doesn't specify what kind of AA batteries.

Later in the manual, it describes how you can change the battery meter
voltage thresholds. The two settings are "A" for alkaline and "n" for
"NiMH or NiCad rechargeable". That's a direct quote from the manual.
So it's clearly intended to work with NiCd cells.

The Motorola NiMH pack is somewhat weird - its capacity is only 550 mAH.
I wonder if they use 4 AAA cells in it to get 4.8 V for higher transmit
power (but short battery life). It also has contacts that mate with
charging contacts on the battery compartment cover, which in turn mate
with contacts on the Motorola charger. This ensures that only the
Motorola rechargeable pack can be charged inside the radio.

Dave

lcoe wrote:

Ted, or anyone, i bot a RShack "Auto Sensing" model (for ni-cad and lithium).
the manual and box says, "automatically senses full charge and shuts off".
further, in the manual it says, '`...charge only fully discharged cells...'

I replied to this but don't see it and my ISP has been having the
nasties so:

I wouldn't trust it but YMMV. First off, they don't mention delt-V
termination or NiMH. Second, there should be no need to fully discharge
cells before charging if it were truly a smart charger.

another feature is a "backup" fixed timer, 1.5hr for nicad, 2.0 for lith.
it's RS model 23-405, 50% off recently. it's heavy, brick shaped, but
is it really fully automatic?

I don't think so and wouldn't trust it but I haven't personally seen
it. I *know* the Maha's are good.

Ted

Old Nick......
Adding the extra NiCad cell as you suggested will give you a total of 4.8
V.... very close to what 3 fresh alkaline batteries will put out. An
eloquent solution that I have seen in some consumer equipment over the years
is to use (2) AAA cells and (2) 1/2AAA cells. The 1/2 cells obviously
won't have the capacity of a larger full size AAA cell, but the radio will
operate correctly with the voltage boost....... and all the batteries can
fit in the radio's battery compartment without the need for "ugly"
modifications and "add ons".
The "half" cells in the AAA size can be difficult to find but they are
available.......
--
Best Regards,
Daniel Sofie
Electronics Supply & Repair
-----------------------------

I'm sorry. I've got so many of these--of several different models--that I
can't pull up just where I saw that info. I checked to be sure, because I
have NiCds I could be using. Nimh's work great, and alkaline usage is
acceptable...unless I have a crew of 11 guys all trying to keep in touch.
Then I go through a case of them in a week or so.

I'm sure I saw this info somewhere...it may have been one particular model.
The 280 manual (only one which I was able to put my hands on easily) doesn't
mention NiCd's at all...just rechargeable alk's. We've got 280's, 250's,
6220's, FR-60's--among others.

jak

"Dave Martindale" wrote in message
...
"jakdedert" writes:
All the Motorola FRS radios (that I'm familiar with) use three AA cells.
All of their literature states that alkalines or Nimhs *must* be used.
According to Motorola, NiCads are not acceptable.

That's not true of the T6210. In the battery installation section, it
just says "AA batteries" or a special NiMH pack sold by Motorola. It
doesn't specify what kind of AA batteries.

Later in the manual, it describes how you can change the battery meter
voltage thresholds. The two settings are "A" for alkaline and "n" for
"NiMH or NiCad rechargeable". That's a direct quote from the manual.
So it's clearly intended to work with NiCd cells.

The Motorola NiMH pack is somewhat weird - its capacity is only 550 mAH.
I wonder if they use 4 AAA cells in it to get 4.8 V for higher transmit
power (but short battery life). It also has contacts that mate with
charging contacts on the battery compartment cover, which in turn mate
with contacts on the Motorola charger. This ensures that only the
Motorola rechargeable pack can be charged inside the radio.

Dave

Remember - NiCad are 1.25 volts per cell. To low for some electronics
to function when in a higher voltage circuit.

Martin
--
Martin Eastburn, Barbara Eastburn
@ home at Lion's Lair with our computer
NRA LOH, NRA Life
NRA Second Amendment Task Force Charter Founder

In rec.crafts.metalworking Eastburn wrote:
Remember - NiCad are 1.25 volts per cell. To low for some electronics
to function when in a higher voltage circuit. Martin

1.2, right? also, i now find that the NiMH are also 1.2(!). --Loren

--
Martin Eastburn, Barbara Eastburn
@ home at Lion's Lair with our computer
NRA LOH, NRA Life
NRA Second Amendment Task Force Charter Founder

In article , (Dave Martindale) wrote:
Eastburn writes:
Remember - NiCad are 1.25 volts per cell. To low for some electronics
to function when in a higher voltage circuit.

It's actually easier to design circuits to work properly on NiCd and
NiMh, since the voltage is close to 1.2 V per cell for almost the entire
discharge life of the cell.

In comparison, alkaline cells deliver 1.5 V when new but drop to 1.0 V
or less at end of life (depending on current). Any device that wants to
use alkaline cells should be designed to operate all the way down to 1 V

Forgot to mention high output current where Nicad is king, Nimh second, and
alkaline third. An alkaline will output perhaps 1.2 volts or less at high current.
On the other hand, there is a GE discount CB walkie-talkie that has been sold
in many discount outlets. It uses a fixed amount of cells. It will ONLY work with alkalines.
It NEEDS the extra voltage for the thing to output any decent power, 5 watts, where
the 1.2 volt cells will cause it to output 1/10th proper power level or 500mw.

greg

(GregS) writes:

On the other hand, there is a GE discount CB walkie-talkie that has been sold
in many discount outlets. It uses a fixed amount of cells. It will ONLY
work with alkalines.
It NEEDS the extra voltage for the thing to output any decent power, 5
watts, where
the 1.2 volt cells will cause it to output 1/10th proper power level or 500mw.

Which means that it will use half or less of the energy in one set of
alkaline cells before you have to replace them with new ones.

This certainly fits my definition of "junk".

Dave

My old Olympus D-320L digicam goes through alkalines like crazy...but when
they won't work in the camera anymore, they still have plenty of capacity
for flashlights and the like.

I'll have to measure the open circuit voltage the next time I change them,
IIRC it was something like 1.3 volts.

jak

"Dave Martindale" wrote in message
...
(GregS) writes:

On the other hand, there is a GE discount CB walkie-talkie that has been
sold
in many discount outlets. It uses a fixed amount of cells. It will ONLY
work with alkalines.
It NEEDS the extra voltage for the thing to output any decent power, 5
watts, where
the 1.2 volt cells will cause it to output 1/10th proper power level or
500mw.

Which means that it will use half or less of the energy in one set of
alkaline cells before you have to replace them with new ones.

This certainly fits my definition of "junk".

Dave

Quit interesting that you said that. Based on some of these posts, I am
going to check the next set of alkalines out of my HP 215. If it has the
same problem, then I bet the NiMH's won't be any better. God I hope not, I
sure would like a rechargeable solution.

Maury.

PS, All these conversations have my invention mind going; If I hit the big
time and get rich, I may throw you all a bone or something. :-)


"jakdedert" wrote in message
...
My old Olympus D-320L digicam goes through alkalines like crazy...but when
they won't work in the camera anymore, they still have plenty of capacity
for flashlights and the like.

I'll have to measure the open circuit voltage the next time I change them,
IIRC it was something like 1.3 volts.

jak

"Dave Martindale" wrote in message
...
(GregS) writes:

On the other hand, there is a GE discount CB walkie-talkie that has
been
sold
in many discount outlets. It uses a fixed amount of cells. It will ONLY
work with alkalines.
It NEEDS the extra voltage for the thing to output any decent power, 5
watts, where
the 1.2 volt cells will cause it to output 1/10th proper power level or
500mw.

Which means that it will use half or less of the energy in one set of
alkaline cells before you have to replace them with new ones.

This certainly fits my definition of "junk".

Dave

"Eastburn" wrote in message
...
Remember - NiCad are 1.25 volts per cell. To low for some electronics
to function when in a higher voltage circuit.

Bingo... voltage = Alkalines, current = NiMH or Cd.

Also - Fry's had 2300mAh AA's when I was there yesterday. $13 for four of
them. YIKES!

Venger

"CMF" writes:
Quit interesting that you said that. Based on some of these posts, I am
going to check the next set of alkalines out of my HP 215. If it has the
same problem, then I bet the NiMH's won't be any better. God I hope not, I
sure would like a rechargeable solution.

You need to measure the voltage under load. That's particularly
important with high-current devices like a digital camera, or a 5 W
radio transmitter. There are some devices where the internal resistance
of the alkalines is the problem, not the design of the device.

For example, suppose you have a digicam that uses 2 AA cells, and it's
been properly designed to operate down to a voltage of 2 V. A pair of
alkalines start out a 3 V, but the camera sometimes draws enough current
(particularly with the LCD backlight on, and when recharging the flash)
that the voltage *under load* drops to 1.3 V. So far so good.

Now, after you've taken a few photos, the alkalines have dropped to a
no-load voltage of 1.3 V - meaning they still have most of their
capacity remaining. But the internal resistance increases as you
discharge the cells. Now, when you take a picture, the high current
momentarily causes the battery voltage to drop from 1.3 V to below 1 V,
and the camera shuts down.

NiCd and NiMH cells have *much* lower internal resistance than alkaline
cells, and it stays much lower throughout the discharge life of the
cells. These cells can deliver several amps of current with very little
voltage drop. So, although a pair of cells produce only 2.4 V, you
still get something like 2.3 V or 2.2 V under heavy load until the
battery is almost completely dead - and the camera continues working.

Basically, if alkaline cells power a device for a longer time than
current NiMH cells, then either the device has very low current drain
(where alkaline still does have more capacity), or the device hasn't
been designed to operate all the way down to 1 V per cell (bad design).
While if NiMH cells operate the device longer than alkaline cells, it's
probably because the device draws lots of current and the alkaline cells
have too much internal resistance.

Dave

Actually, after borrowing a decent electronic multi-tester (would love to
buy one but if I had that kind of money I wouldn't be selling ironing
boards) I will rig to the power connections inside the camera and wire it to
a makeshift battery pack and test that. I can see how to do it now. I will
probably use some 24 gauge wire from a cat5 cable unless you think that will
not be enough.

As for measuring the way I did already, there are four batteries, two each
that drop down two slots and connect to the power leads inside the camera.
The lid closes the circuit, so I am testing the four batteries and the
camera circuitry I guess, with the lid open. I don't know how valid that
test is, but I am having fun.

Instead of all this testing, I could just get the charger and some
batteries, I just don't want to find out it won't work because this camera,
apparently an older model of the HP215, needs the alkaline voltage rush, so
to speak.

"Dave Martindale" wrote in message
...
"CMF" writes:

Okay, let me ask, how do I test under load? Does this mean see what
happens
to the voltage while in the camera, or when snapping a picture?

Ideally, yes. If you can't do that because you can't reach the camera's
battery terminals with the battery installed, maybe you can use clip
leads to connect the batteries (in a battery holder) to the camera
terminals. And if you can't do that either, perhaps you can measure the
current drawn by the camera, and then use a resistor that draws about
the same amount of current. What's practical depends on the mechanical
layout of your camera.

I was
piddling around with it this morning using an analog Sperry SP-152a
multitester, and it was showing 5 volts when I just took the battery cap
off
and touched the leads, where if I took all four batterys out and laid end
to
end, it showed 6. Remember, I am virtually ignorant of this stuff, and ha
ve
a cheap tester. The same tester shows almost 2 volts per battery, so I am
limited by a silly tester.

What in the camera is taking almost an entire volt even with the camera
turned off?

If you "take the battery cap off", what does the complete circuit with
the multimeter look like? Are you connecting the meter from the same
point where the camera takes its power? Or are you really removing an
inter-battery connection from the "far" end of the batteries and
measuring the voltage between the two exposed battery ends, but with the
camera electronics still in the loop?

If you're just measuring between two batteries in the middle of the
battery string, but the camera is also still in the circuit, the voltage
you measure just depends on the relative resistance of your meter and
the camera electronics in the "off" state, which is pretty meaningless.
If the camera had a mechanical "off" switch, you'd actually measure zero
volts in this case.

Dave

|Instead of all this testing, I could just get the charger and some
|batteries, I just don't want to find out it won't work because this camera,
|apparently an older model of the HP215, needs the alkaline voltage rush, so
|to speak.

As soon as I find my other two NiMh AAs, I'll pop them in my HP215 camera. I
have no doubt they will work fine. Will report.

On Tue, 15 Jul 2003 19:06:25 +0000 (UTC), (Dave
Martindale) wrote something
.......and in reply I say!:

Sigh! G As the starter of this portion of the thread, I must remind
you they _are_ Uniden :- They seemed like a good idea at the time.

In other words, it's a
piece of junk.

************************************************** ****************************************
Huh! Old age!. You may hate it, but let me tell you, you can't get by for long without it!

Nick White --- HEAD:Hertz Music
Please remove ns from my header address to reply via email
!!
")
_/ )
( )
_//- \__/

On Mon, 14 Jul 2003 15:27:05 -0700, "Sofie" wrote
something
.......and in reply I say!:

What about Dick Smith electronics????

wh....Oh, the half cells. I will give them a go. But they are not the
"electronics" shop they once were.
------------------------



"Old Nick" wrote in message
...
On Sat, 12 Jul 2003 17:34:37 -0700, "Sofie" wrote
something
......and in reply I say!:

************************************************** ****************************************
Huh! Old age!. You may hate it, but let me tell you, you can't get by for long without it!

Nick White --- HEAD:Hertz Music
Please remove ns from my header address to reply via email
!!
")
_/ )
( )
_//- \__/