Heres a couple of questions for someone who knows about batteries.

I have two hand held radios which I rarely use. An Alinco dual bander with
Nmhi batteries, and a commercial UHF with Nicad batteries. Both sets of
batteries are in good order and hold a charge well. I can leave them for
months and when I pick the radios up, they still have a good charge in them.

Today I lifted both radios, the first time in a month or two, and both had
totally flat batteries. I know both were fully charged when I last switched
them off. What happened? The weather has got warmer in the last month, and
the humidity levels are up. But nothing else has changed. What flattened
them both?

Also...

Last time I took a hand held radio abroad, I took 2 sets of batteries. Both
were fully charged when they were packed. Both were flat when I reached my
destination. Same with my mobile phone and camera batteries as well. All
were nearly flat and had not been switched on during the journey. What is it
that makes batteries go flat when travelling in a pressurised aircraft?

I hope someone can advise. I've been thinking about the aircraft one for
ages )

73
--
Jack VK2CJC / MM0AXL
FISTS #9666
CW Ops QRP Club #753
Mid North Coast Amateur Radio Group
www.mncarg.org

Jack VK2CJC wrote:
Heres a couple of questions for someone who knows about batteries.

I have two hand held radios which I rarely use. An Alinco dual bander with
Nmhi batteries, and a commercial UHF with Nicad batteries. Both sets of
batteries are in good order and hold a charge well. I can leave them for
months and when I pick the radios up, they still have a good charge in them.

Today I lifted both radios, the first time in a month or two, and both had
totally flat batteries. I know both were fully charged when I last switched
them off. What happened? The weather has got warmer in the last month, and
the humidity levels are up. But nothing else has changed. What flattened
them both?

Also...

Last time I took a hand held radio abroad, I took 2 sets of batteries. Both
were fully charged when they were packed. Both were flat when I reached my
destination. Same with my mobile phone and camera batteries as well. All
were nearly flat and had not been switched on during the journey. What is it
that makes batteries go flat when travelling in a pressurised aircraft?

I hope someone can advise. I've been thinking about the aircraft one for
ages )

Nothing in an airplane makes batteries go flat.

Commercial aircraft are pressurized to an equivelant altitude of around
7-8 thousand feet.

I regularly fly at those altitudes in my unpressurized aircraft with
the backup handheld in a seat pouch and the batteries are just fine.

Perhaps the batteries aren't as good as you think or the last charge
was longer ago than you remember.

--
Jim Pennino

Remove .spam.sux to reply.

Perhaps the batteries aren't as good as you think or the last charge
was longer ago than you remember.

4 sets of batteries were all good order and fully charged the day before
leaving and were all flat or almost flat on arrival.

I cant think of any reason why either. Its an odd one )

And it wasn't a one off, I've done this journey a few times, and had the
same results. Its a long trip, UK to Australia, 3 flights, 22 hours in the
air. But radio, camera and phone were not switch on during this time.

Suggestions welcome................

"Jack VK2CJC" wrote ...
Perhaps the batteries aren't as good as you think or the last charge
was longer ago than you remember.

4 sets of batteries were all good order and fully charged the day
before leaving and were all flat or almost flat on arrival.

I cant think of any reason why either. Its an odd one )

And it wasn't a one off, I've done this journey a few times, and had
the same results. Its a long trip, UK to Australia, 3 flights, 22
hours in the air. But radio, camera and phone were not switch on
during this time.

Suggestions welcome................

If these are commercial flights, are they going through
any kind of imaging screening equipment? What kind?

If these are commercial flights, are they going through
any kind of imaging screening equipment? What kind?

Excellent point Richard.

In recent years all luggage is x-rayed. My wife is a radiographer and always
takes an interest in the machinery. She has never seen this particular type
of imaging before. It shows different types of metal as different colours.
Despite the commonly used name, its not really x-ray, indicated by the lack
of concern of leaked radiation ) Its definitely magnetic.

Could this be the battery killer?

Jack

"Jack VK2CJC" wrote ...
If these are commercial flights, are they going through
any kind of imaging screening equipment? What kind?

Excellent point Richard.

In recent years all luggage is x-rayed. My wife is a radiographer and
always takes an interest in the machinery. She has never seen this
particular type of imaging before. It shows different types of metal as
different colours.
Despite the commonly used name, its not really x-ray, indicated by the
lack of concern of leaked radiation ) Its definitely magnetic.

Could this be the battery killer?

So are they just discharged? Can you recharge them?
Or are they destroyed? Were the radios affected?

If you can see the scanning equipment, can you at least
get a manufacturer name from it? And maybe a model
number? With that, you could do some internet research
to discover what method it uses and if there are any other
reports of bad interactions with batteries, etc.

Richard KE7GKP

Heres a couple of questions for someone who knows about batteries.

I have two hand held radios which I rarely use. An Alinco dual bander with
Nmhi batteries, and a commercial UHF with Nicad batteries. Both sets of
batteries are in good order and hold a charge well. I can leave them for
months and when I pick the radios up, they still have a good charge in
them.

Today I lifted both radios, the first time in a month or two, and both had
totally flat batteries. I know both were fully charged when I last
switched them off. What happened? The weather has got warmer in the last
month, and the humidity levels are up. But nothing else has changed. What
flattened them both?

Also...

Last time I took a hand held radio abroad, I took 2 sets of batteries.
Both were fully charged when they were packed. Both were flat when I
reached my destination. Same with my mobile phone and camera batteries as
well. All were nearly flat and had not been switched on during the
journey. What is it that makes batteries go flat when travelling in a
pressurised aircraft?


All secondary batteries have a self discharge rate, some types are higher
than others, a couple of months is more than sufficient to self discharge a
battery pack. Another factor to take into consideration is that most modern
handhelds do not have a 'hard' on/off switch. There is always a small
standby current drawn. It is best to actually remove the pack from the
radio.

As far as batteries on aircraft; I have never had any problems, and I can't
think of a mechanism that would discharge them.

regards
Jeff

Just out of curiosity, does this happen when the batteries are removed from
the radio also? Try carrying the batteries in a separate battery holder
next time and see if they suffer the same fate.



"Jack VK2CJC" wrote in message
...
Heres a couple of questions for someone who knows about batteries.

I have two hand held radios which I rarely use. An Alinco dual bander with
Nmhi batteries, and a commercial UHF with Nicad batteries. Both sets of
batteries are in good order and hold a charge well. I can leave them for
months and when I pick the radios up, they still have a good charge in
them.

Today I lifted both radios, the first time in a month or two, and both had
totally flat batteries. I know both were fully charged when I last
switched them off. What happened? The weather has got warmer in the last
month, and the humidity levels are up. But nothing else has changed. What
flattened them both?

Also...

Last time I took a hand held radio abroad, I took 2 sets of batteries.
Both were fully charged when they were packed. Both were flat when I
reached my destination. Same with my mobile phone and camera batteries as
well. All were nearly flat and had not been switched on during the
journey. What is it that makes batteries go flat when travelling in a
pressurised aircraft?

I hope someone can advise. I've been thinking about the aircraft one for
ages )

73
--
Jack VK2CJC / MM0AXL
FISTS #9666
CW Ops QRP Club #753
Mid North Coast Amateur Radio Group
www.mncarg.org

In article ,
"Jack VK2CJC" wrote:

Heres a couple of questions for someone who knows about batteries.

I have two hand held radios which I rarely use. An Alinco dual bander with
Nmhi batteries, and a commercial UHF with Nicad batteries. Both sets of
batteries are in good order and hold a charge well. I can leave them for
months and when I pick the radios up, they still have a good charge in them.

Today I lifted both radios, the first time in a month or two, and both had
totally flat batteries. I know both were fully charged when I last switched
them off. What happened? The weather has got warmer in the last month, and
the humidity levels are up. But nothing else has changed. What flattened
them both?

Also...

Last time I took a hand held radio abroad, I took 2 sets of batteries. Both
were fully charged when they were packed. Both were flat when I reached my
destination. Same with my mobile phone and camera batteries as well. All
were nearly flat and had not been switched on during the journey. What is it
that makes batteries go flat when travelling in a pressurised aircraft?

I hope someone can advise. I've been thinking about the aircraft one for
ages )

73

there is probably a few thing gong on

firstly when you saythe batteries are 'fully' charged are you shooting
from the hip or actually measure both volts AND amps?

if not that your premise, 'batteries are fully charged' isn't prob as
good as you thought

as you stated you've had these batteries over time as they age they
have diminished capacity , they will not hold the amp/hr rate for as
long UNDER full LOAD while a quick voltage check or radio on test
might make it appear

the things the other folks said are also true higher temp will reduce
the battery life for example , that radios also have a small draw
current even when off etc

it's highly doubtful any 'xray' or other screaning machine at airports
had any significant effect millions go thru if everyone had problems
we'd hear about it by now

if you want to learn about the machines and are afraid to ask the clerks
just google it btw i've never seen a machine w/o a name tag but u
do have to know where to look perhaps some were removed


all these things added up are significant (except luggage
screaning)

what most likely happening is that the vibration of the plain caused
the power switch to turn on drain the battery and switch off alot
of strange things happen in packing .... removing the battery and
taping over the contacts should help

otherwise i'd suspect your batteries might just be old and not up to
full snuff

you'd have to make a controlled scienfitic test to be sure whats going
on

best of luck and holidayz