Turned on the ancient Sony FM portable this AM and noticed
that the red tuning LED was not coming on even though the
signal seemed ok.

It runs on 4 rechargeables, currently a set of 2008 Eneloops
which were recharged about a week ago, but have only been in
use in the radio for couple of months (normally used in a Ricoh
Caplio camera)

Out of interest I took them out and measured the volts.
Out of the 4 batteries, two (inline) measured 1.29 volts
while the other two measured MINUS 0.094 volts !!??.

What's going on ?.

I put them back in the 7-day-shop intelligent charger and
they registered as empty on the LCD screen but after only
a minute they were reading 1.29 volts and after 15
minutes 1.34 volts by which time the lcd screen suggested
they were half charged.

What's going on ?. Is the charger at fault, or is the
radio causing this ?.

For some time I have noticed a strange, faint drum-beating
sound from the radio even when it is switched off.


Andrew

Andrew wrote:

Out of the 4 batteries, two (inline) measured 1.29 volts
while the other two measured MINUS 0.094 volts !!??.

What's going on ?.

over-discharge

https://en.wikipedia.org/wiki/Nickel%E2%80%93metal_hydride_battery#Over-discharge

On 02/02/2020 09:43, Andrew wrote:
Turned on the ancient Sony FM portable this AM and noticed
that the red tuning LED was not coming on even though the
signal seemed ok.

It runs on 4 rechargeables, currently a set of 2008 Eneloops
which were recharged about a week ago, but have only been in
use in the radio for couple of months (normally used in a Ricoh
Caplio camera)

Out of interest I took them out and measured the volts.
Out of the 4 batteries, two (inline) measured 1.29 volts
while the other two measured MINUS 0.094 volts !!??.

What's going on ?.

I put them back in the 7-day-shop intelligent charger and
they registered as empty on the LCD screen but after only
a minute they were reading 1.29 volts and after 15
minutes 1.34 volts by which time the lcd screen suggested
they were half charged.

What's going on ?. Is the charger at fault, or is the
radio causing this ?.

For some time I have noticed a strange, faint drum-beating
sound from the radio even when it is switched off.


Andrew
driven into reverse charge by the better cells

Not unusual



--
I would rather have questions that cannot be answered...
....than to have answers that cannot be questioned

Richard Feynman

The issue is common and is why some batteries die. When batteries go down,
some will discharge faster than others. This means that in effect if the
device is capable of running on a lower voltage. all the current supplied by
the still good batteries will go through the discharged ones, backwards, in
effect reverse charging them. Depending on the technology of the battery, it
will either ruin them, or just hasten their final demise. Sadly I've never
found an answer to this series battery dilemma and I tend to try to batch
test them and move all the ones that discharge first into some device with
low current needs, and try to pair up matching ones. Its a pain but part of
life these days.
This is also why I hate chargers that charge batteries in series as well,
since this cooks some batteries while the others are still charging. Many
portable phones etc, do this for cheapness and I'm always finding them
clapped out and hot.
Brian

--
----- --
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please
Note this Signature is meaningless.!
"Andrew" wrote in message
...
Turned on the ancient Sony FM portable this AM and noticed
that the red tuning LED was not coming on even though the
signal seemed ok.

It runs on 4 rechargeables, currently a set of 2008 Eneloops
which were recharged about a week ago, but have only been in
use in the radio for couple of months (normally used in a Ricoh
Caplio camera)

Out of interest I took them out and measured the volts.
Out of the 4 batteries, two (inline) measured 1.29 volts
while the other two measured MINUS 0.094 volts !!??.

What's going on ?.

I put them back in the 7-day-shop intelligent charger and
they registered as empty on the LCD screen but after only
a minute they were reading 1.29 volts and after 15
minutes 1.34 volts by which time the lcd screen suggested
they were half charged.

What's going on ?. Is the charger at fault, or is the
radio causing this ?.

For some time I have noticed a strange, faint drum-beating
sound from the radio even when it is switched off.


Andrew

On 02/02/2020 09:55, The Natural Philosopher wrote:
On 02/02/2020 09:43, Andrew wrote:


Andrew
driven into reverse charge by the better cells

Not unusual



+1

On 02/02/2020 09:55, The Natural Philosopher wrote:
On 02/02/2020 09:43, Andrew wrote:
Turned on the ancient Sony FM portable this AM and noticed
that the red tuning LED was not coming on even though the
signal seemed ok.

It runs on 4 rechargeables, currently a set of 2008 Eneloops
which were recharged about a week ago, but have only been in
use in the radio for couple of months (normally used in a Ricoh
Caplio camera)

Out of interest I took them out and measured the volts.
Out of the 4 batteries, two (inline) measured 1.29 volts
while the other two measured MINUS 0.094 volts !!??.

What's going on ?.

I put them back in the 7-day-shop intelligent charger and
they registered as empty on the LCD screen but after only
a minute they were reading 1.29 volts and after 15
minutes 1.34 volts by which time the lcd screen suggested
they were half charged.

What's going on ?. Is the charger at fault, or is the
radio causing this ?.

For some time I have noticed a strange, faint drum-beating
sound from the radio even when it is switched off.


Andrew
driven into reverse charge by the better cells

Not unusual




It was a set of four that have had similar usage.

On 02/02/2020 13:34, Andrew wrote:
On 02/02/2020 09:55, The Natural Philosopher wrote:
On 02/02/2020 09:43, Andrew wrote:
Turned on the ancient Sony FM portable this AM and noticed
that the red tuning LED was not coming on even though the
signal seemed ok.

It runs on 4 rechargeables, currently a set of 2008 Eneloops
which were recharged about a week ago, but have only been in
use in the radio for couple of months (normally used in a Ricoh
Caplio camera)

Out of interest I took them out and measured the volts.
Out of the 4 batteries, two (inline) measured 1.29 volts
while the other two measured MINUS 0.094 volts !!??.

What's going on ?.

I put them back in the 7-day-shop intelligent charger and
they registered as empty on the LCD screen but after only
a minute they were reading 1.29 volts and after 15
minutes 1.34 volts by which time the lcd screen suggested
they were half charged.

What's going on ?. Is the charger at fault, or is the
radio causing this ?.

For some time I have noticed a strange, faint drum-beating
sound from the radio even when it is switched off.


Andrew
driven into reverse charge by the better cells

Not unusual




It was a set of four that have had similar usage.

so what? some are always better than others

--
€œIt is hard to imagine a more stupid decision or more dangerous way of
making decisions than by putting those decisions in the hands of people
who pay no price for being wrong.€�

Thomas Sowell

Brian Gaff (Sofa 2) wrote

No idea what the drumming sound is, a
spider trying to attract a mate perhaps?

No spiders do that. More likely one got infected
with the heavy metal **** he played on it.

"The Natural Philosopher" wrote in message
...
On 02/02/2020 09:43, Andrew wrote:
Turned on the ancient Sony FM portable this AM and noticed
that the red tuning LED was not coming on even though the
signal seemed ok.

It runs on 4 rechargeables, currently a set of 2008 Eneloops
which were recharged about a week ago, but have only been in
use in the radio for couple of months (normally used in a Ricoh
Caplio camera)

Out of interest I took them out and measured the volts.
Out of the 4 batteries, two (inline) measured 1.29 volts
while the other two measured MINUS 0.094 volts !!??.

What's going on ?.

I put them back in the 7-day-shop intelligent charger and
they registered as empty on the LCD screen but after only
a minute they were reading 1.29 volts and after 15
minutes 1.34 volts by which time the lcd screen suggested
they were half charged.

What's going on ?. Is the charger at fault, or is the
radio causing this ?.

For some time I have noticed a strange, faint drum-beating
sound from the radio even when it is switched off.


Andrew
driven into reverse charge by the better cells

Not unusual



--
I would rather have questions that cannot be answered...
...than to have answers that cannot be questioned

Richard Feynman

Brian Gaff (Sofa 2) wrote:

No idea what the drumming sound is, a spider trying to attract a mate
perhaps?
Brian

Might it be the LF instability that used to be commonly called
motor-boating?

--

Roger Hayter

On Mon, 3 Feb 2020 02:28:02 +1100, cantankerous trolling geezer Rodent
Speed, the auto-contradicting senile sociopath, blabbered, again:

FLUSH the senile sick idiot's latest troll****

02:28??? LOL Is your unbearable LONELINESS not letting you sleep in again,
you cantankerous senile pest? GOOD!

--
Website (from 2007) dedicated to the 85-year-old trolling senile
cretin from Oz:
https://www.pcreview.co.uk/threads/r...d-faq.2973853/

On Sunday, 2 February 2020 16:45:42 UTC, Roger Hayter wrote:
Brian Gaff (Sofa 2) wrote:

No idea what the drumming sound is, a spider trying to attract a mate
perhaps?
Brian

Might it be the LF instability that used to be commonly called
motor-boating?

....caused by a bad cap.


NT

On 02/02/2020 10:27, Andrew wrote:
On 02/02/2020 09:54, Andy Burns wrote:
Andrew wrote:

Out of the 4 batteries, two (inline) measured 1.29 volts
while the other two measured MINUS 0.094 volts !!??.

What's going on ?.

over-discharge

https://en.wikipedia.org/wiki/Nickel%E2%80%93metal_hydride_battery#Over-discharge


Ok, that means the Radio is at fault then, hence the odd faint drumming
noise it makes when it is 'off'.

Time to visit JL or similar for a replacement radio that runs on mains
(as this one did until I dropped it while doing some outside DIY and
it landed on a corner whereby the impact broke the internal mains
transformer away from the circuit board).


You have a device which has easily accessible DC power inputs, and is
capable of handing a wide range of DC inputs (4 to 6v).
This is the same range of voltage that 90% of mobile chargers spit out.
USB chargers spit out 5V and your average Nokia/Sony Ericsson
proprietary charger spits out somewhere betweeen 4.5 and 5.7v.

Either find an old charger, a mains USB charger+a 2 or 3m USB cable cut
off the old phone end connector, verify the polarity and solder the
wires onto the battery terminals. Cut a notch in the battery cover to
let the wire in - done.

If you want to get clever, either make 2 dummy batteries out of 10mm
dowelling and terminate the wires to screws, mark the + and - terminals.
or cleaner still - buy a 2.1mm panel mounting dc barrel connector and
matching cable connector. Open the radio, connect the tip of the
connector to the radio and battery +ve terminal, connect the sleeve
terminal to the radio -ve wire, and the switch terminal to the battery
-ve. Verify that inserting the (dead) plug into the socket turns the
radio off when running off batteries, then wire the plug to the charger,
and mount the socket in a freshly drilled hole in the case.

For the record - I've had a Sony Ericsson CST-60 charger powering an
Ikea Molgan PIR light (3xAAA) glued on top as a landing nightlight for
years...

On 02/02/2020 13:34, Andrew wrote:
On 02/02/2020 09:55, The Natural Philosopher wrote:
On 02/02/2020 09:43, Andrew wrote:
Turned on the ancient Sony FM portable this AM and noticed
that the red tuning LED was not coming on even though the
signal seemed ok.

It runs on 4 rechargeables, currently a set of 2008 Eneloops
which were recharged about a week ago, but have only been in
use in the radio for couple of months (normally used in a Ricoh
Caplio camera)

Out of interest I took them out and measured the volts.
Out of the 4 batteries, two (inline) measured 1.29 volts
while the other two measured MINUS 0.094 volts !!??.

What's going on ?.

For some time I have noticed a strange, faint drum-beating
sound from the radio even when it is switched off.

Elves inside trying to get out.

driven into reverse charge by the better cells

Not unusual

It was a set of four that have had similar usage.

In any set of four there is always a weakest cell. The first one to fail
will have current flowing through it driven by the remaining good ones.
Leakage is often a problem if the cell is abused in this way for long.

Devices that will tolerate a wide range of input voltages tend to cause
this sort of problem most often. Many higher current devices have an
absolute minimum voltage where they will work and shut down gracefully
to avoid driving any weaker cells into reverse bias. LCD based kit tends
to self limit when you can no longer read the display on it.

--
Regards,
Martin Brown