I have (elsewhere) previous been recommended to buy a power bank to uses as
an emergency back up for my portable devices.

Which, because I have a candy bar phone with a standby time of 3 weeks,
means my tablet and camera.

I was in a shop today, saw one on sale with "for smartphones and tablets" at
a reasonable price and bought it

but after I looked at the back it said output 5V 1A.

Oh!

ISTR that when I bought my in-car USB charger I got one for phones and had
to take it back and get a higher rated one for Tablets. And even then, one
of my tabs reports that it isn't powerful enough to "charge" the device,
though experimentation shows that it does keep it operating for a bit
longer. Plugging my camera in and it doesn't even notice that there's a
charge there.

So I went into all the other shops in the high street to see what they had
(lest I should want to take the purchase back whist I was still there) and
all of them, with one single exception were output 5V 1A, that exception was
fugging expensive and more importantly 3 times the dimensions and 10 times
the weight of the one that I had bought. I particularly wanted a small,
lightweight, fits in your pocket example.

Back home I looked at my plug in the wall USB chargers, which I
(successfully) use interchangeably on all my devices and one says output 5V
2A and the other output 5V 1A.

What's going on here?

what rating do I need to charge my device(s)

I did a quick Google to see if I could find out and found "5 Key Things To
Know When Buying A Power Bank" and one of them is "When you buy a portable
power bank, make sure that it can charge the battery of a specific device"
Yeah, I know that? But how do I find out what that requirement is - I came
here expecting that you were going to tell me as the manufactures of these
devices keep it as secret as the coca cola recipe (I have been online and
downloaded the full specs).

So the item in question is still in its unopened box with all the seals
intact (as it's from one of these shops that aren't the best for taking
stuff back to). do I take it back and seek out a more powerful one, or open
it and try it, and risk the shop refusing my returning it?

tim

On 04/11/2017 14:50, tim... wrote:

So I went into all the other shops in the high street to see what they
had (lest I should want to take the purchase back whist I was still
there) and all of them, with one single exception were output 5V 1A,
that exception was fugging expensive and more importantly 3 times the
dimensions and 10 times the weight of the one that I had bought.Â* I
particularly wanted a small, lightweight, fits in your pocket example.

You can't miniaturise the Watt

Bill

In article ,
tim... wrote:
ISTR that when I bought my in-car USB charger I got one for phones and had
to take it back and get a higher rated one for Tablets. And even then, one
of my tabs reports that it isn't powerful enough to "charge" the device,
though experimentation shows that it does keep it operating for a bit
longer. Plugging my camera in and it doesn't even notice that there's a
charge there.

Do all those devices have a 'standard' USB 5v charger as supplied? None of
my laptops etc do.

--
*OK, who stopped payment on my reality check?

Dave Plowman London SW
To e-mail, change noise into sound.

On 04/11/17 14:50, tim... wrote:
I have (elsewhere) previous been recommended to buy a power bank to uses
as an emergency back up for my portable devices.

Which, because I have a candy bar phone with a standby time of 3 weeks,
means my tablet and camera.

I was in a shop today, saw one on sale with "for smartphones and
tablets" at a reasonable price and bought it

but after I looked at the back it said output 5V 1A.


The key figure is the capacity, measured in milliamperehours (mAh),
typically on the cheap power banks 1200mAh. It will be stated on the
packaging somewhere.

The 5V is the standard voltage for USB and 1A is the maximum rate at
which it can charge your phone. So at 2A the phone will be charged in
half the time it will take at 1A (assuming the phone can take it which I
doubt).

The cheap power banks seldom have the claimed capacity but, for
emergency top ups, does it matter that the phone will only be charged to
half its maximum?

Another Dave

--
Change nospam to techie

On 04/11/17 14:50, tim... wrote:
I have (elsewhere) previous been recommended to buy a power bank to uses
as an emergency back up for my portable devices.

Which, because I have a candy bar phone with a standby time of 3 weeks,
means my tablet and camera.

I was in a shop today, saw one on sale with "for smartphones and
tablets" at a reasonable price and bought it

but after I looked at the back it said output 5V 1A.


The key figure is the capacity, measured in milliamperehours (mAh),
typically on the cheap power banks 1200mAh. It will be stated on the
packaging somewhere.

The 5V is the standard voltage for USB and 1A is the maximum rate at
which it can charge your phone. So at 2A the phone will be charged in
half the time it will take at 1A (assuming the phone can take it which I
doubt).

The cheap power banks seldom have the claimed capacity but, for
emergency top ups, does it matter that the phone will only be charged to
less than its maximum?

Another Dave

--
Change nospam to techie

"Bill Wright" wrote in message
news
On 04/11/2017 14:50, tim... wrote:

So I went into all the other shops in the high street to see what they
had (lest I should want to take the purchase back whist I was still
there) and all of them, with one single exception were output 5V 1A, that
exception was fugging expensive and more importantly 3 times the
dimensions and 10 times the weight of the one that I had bought. I
particularly wanted a small, lightweight, fits in your pocket example.

You can't miniaturise the Watt

The difference is prices/size is to do with the capacity of the battery,
sure

But I'm not bothered by having a power store that will only re-charge my
device once, rather than 5 times.

It's the possibility that a low power output doesn't charge it at all,
that's the problem

"Dave Plowman (News)" wrote in message
...
In article ,
tim... wrote:
ISTR that when I bought my in-car USB charger I got one for phones and
had
to take it back and get a higher rated one for Tablets. And even then,
one
of my tabs reports that it isn't powerful enough to "charge" the device,
though experimentation shows that it does keep it operating for a bit
longer. Plugging my camera in and it doesn't even notice that there's a
charge there.

Do all those devices have a 'standard' USB 5v charger as supplied? None of
my laptops etc do.

the tabs do

The camera came with an external charge unit that you insert the battery
into to recharge it, but also accepts a USB charge whilst in situ in the
camera - Plugging in either of my tablet USB chargers recharges it so I have
never ever taken the battery out of the camera, through trying to charge it
from my car USB port resulted in a failure to charge

tim





--
*OK, who stopped payment on my reality check?

Dave Plowman London SW
To e-mail, change noise into sound.

"Another Dave" wrote in message
news
On 04/11/17 14:50, tim... wrote:
I have (elsewhere) previous been recommended to buy a power bank to uses
as an emergency back up for my portable devices.

Which, because I have a candy bar phone with a standby time of 3 weeks,
means my tablet and camera.

I was in a shop today, saw one on sale with "for smartphones and tablets"
at a reasonable price and bought it

but after I looked at the back it said output 5V 1A.


The key figure is the capacity, measured in milliamperehours (mAh),
typically on the cheap power banks 1200mAh. It will be stated on the
packaging somewhere.

I understand that, it is 2000, the expensive one was 10,000 - enough to
recharge a device 4 or 5 times. But I don't need that.

I'm not concerned by the battery capacity, it's the output current that's
the issue here.

The 5V is the standard voltage for USB and 1A is the maximum rate at which
it can charge your phone. So at 2A the phone will be charged in half the
time it will take at 1A (assuming the phone can take it which I doubt).

The devices are tablets, some of them (apparently) wont charge at 1A.

The cheap power banks seldom have the claimed capacity but, for emergency
top ups, does it matter that the phone will only be charged to less than
its maximum?

Nope, not a problem, as long as it works I don't care how inefficient it is.
I really am only going to use this as an emergency back up whilst out during
the day, not as a strategy to avoid plugging my tablet in every evening at
the hotel (or at a location where I'm not staying in a hotel).

I am only concerned that it may not work at all.

tim

On Saturday, 4 November 2017 14:51:58 UTC, tim... wrote:
I have (elsewhere) previous been recommended to buy a power bank to uses as
an emergency back up for my portable devices.

do you need an emergency power backup for them?

Which, because I have a candy bar phone with a standby time of 3 weeks,
means my tablet and camera.

Sounds like a no.

On Saturday, 4 November 2017 15:43:51 UTC, Bill Wright wrote:
On 04/11/2017 14:50, tim... wrote:

So I went into all the other shops in the high street to see what they
had (lest I should want to take the purchase back whist I was still
there) and all of them, with one single exception were output 5V 1A,
that exception was fugging expensive and more importantly 3 times the
dimensions and 10 times the weight of the one that I had bought.Â* I
particularly wanted a small, lightweight, fits in your pocket example.

You can't miniaturise the Watt

Bill

Meet the pmpo watt, a truly miniature watt.


NT

wrote in message
...
On Saturday, 4 November 2017 14:51:58 UTC, tim... wrote:
I have (elsewhere) previous been recommended to buy a power bank to uses
as
an emergency back up for my portable devices.

do you need an emergency power backup for them?

Which, because I have a candy bar phone with a standby time of 3 weeks,
means my tablet and camera.

Sounds like a no.

for the phone no

for may camera and tablet

yes

tim

In article ,
tim... wrote:


"Bill Wright" wrote in message
news
On 04/11/2017 14:50, tim... wrote:

So I went into all the other shops in the high street to see what they
had (lest I should want to take the purchase back whist I was still
there) and all of them, with one single exception were output 5V 1A, that
exception was fugging expensive and more importantly 3 times the
dimensions and 10 times the weight of the one that I had bought. I
particularly wanted a small, lightweight, fits in your pocket example.

You can't miniaturise the Watt

The difference is prices/size is to do with the capacity of the battery,
sure

But I'm not bothered by having a power store that will only re-charge my
device once, rather than 5 times.

It's the possibility that a low power output doesn't charge it at all,
that's the problem

Certainly the case with my iPhone

--
from KT24 in Surrey, England

On Sat, 04 Nov 2017 09:29:16 -0700, tabbypurr wrote:

On Saturday, 4 November 2017 15:43:51 UTC, Bill Wright wrote:
On 04/11/2017 14:50, tim... wrote:

So I went into all the other shops in the high street to see what
they had (lest I should want to take the purchase back whist I was
still there) and all of them, with one single exception were output
5V 1A, that exception was fugging expensive and more importantly 3
times the dimensions and 10 times the weight of the one that I had
bought.Â* I particularly wanted a small, lightweight, fits in your
pocket example.

You can't miniaturise the Watt

Bill

Meet the pmpo watt, a truly miniature watt.

But still larger than the Sinclair watt.



--
My posts are my copyright and if @diy_forums or Home Owners' Hub
wish to copy them they can pay me £1 a message.
Use the BIG mirror service in the UK: http://www.mirrorservice.org
*lightning surge protection* - a w_tom conductor

Well, you can have a higher current for a short time or a lower current for
a longer time, and hence you won't get a good battery that is lightweight if
you need it to charge or power something for a significantly long time. This
is the one problem with batteries I suppose.Also not every bit of kit will
charge faster than its allowed to, look What happened when Samsung made
their phone charge faster on sub standard batteries.
Personally I'd take it back and get a larger device, something that maybe
you wear as a belt with more oomph behind it, as long as your devices can
charge faster, otherwise its not really going to make a lot of difference.
Brian

--
From the Sofa of Brian Gaff Reply address is active
Remember, if you don't like where I post
or what I say, you don't have to
read my posts! :-)
"tim..." wrote in message
news
I have (elsewhere) previous been recommended to buy a power bank to uses as
an emergency back up for my portable devices.

Which, because I have a candy bar phone with a standby time of 3 weeks,
means my tablet and camera.

I was in a shop today, saw one on sale with "for smartphones and tablets"
at a reasonable price and bought it

but after I looked at the back it said output 5V 1A.

Oh!

ISTR that when I bought my in-car USB charger I got one for phones and had
to take it back and get a higher rated one for Tablets. And even then,
one of my tabs reports that it isn't powerful enough to "charge" the
device, though experimentation shows that it does keep it operating for a
bit longer. Plugging my camera in and it doesn't even notice that there's
a charge there.

So I went into all the other shops in the high street to see what they had
(lest I should want to take the purchase back whist I was still there) and
all of them, with one single exception were output 5V 1A, that exception
was fugging expensive and more importantly 3 times the dimensions and 10
times the weight of the one that I had bought. I particularly wanted a
small, lightweight, fits in your pocket example.

Back home I looked at my plug in the wall USB chargers, which I
(successfully) use interchangeably on all my devices and one says output
5V 2A and the other output 5V 1A.

What's going on here?

what rating do I need to charge my device(s)

I did a quick Google to see if I could find out and found "5 Key Things To
Know When Buying A Power Bank" and one of them is "When you buy a portable
power bank, make sure that it can charge the battery of a specific device"
Yeah, I know that? But how do I find out what that requirement is - I
came here expecting that you were going to tell me as the manufactures of
these devices keep it as secret as the coca cola recipe (I have been
online and downloaded the full specs).

So the item in question is still in its unopened box with all the seals
intact (as it's from one of these shops that aren't the best for taking
stuff back to). do I take it back and seek out a more powerful one, or
open it and try it, and risk the shop refusing my returning it?

tim

On 04/11/2017 16:23, tim... wrote:


"Another Dave" wrote in message
news
On 04/11/17 14:50, tim... wrote:
I have (elsewhere) previous been recommended to buy a power bank to
uses as an emergency back up for my portable devices.

Which, because I have a candy bar phone with a standby time of 3
weeks, means my tablet and camera.

I was in a shop today, saw one on sale with "for smartphones and
tablets" at a reasonable price and bought it

but after I looked at the back it said output 5V 1A.


The key figure is the capacity, measured in milliamperehours (mAh),
typically on the cheap power banks 1200mAh. It will be stated on the
packaging somewhere.

I understand that, it is 2000, the expensive one was 10,000 - enough to
recharge a device 4 or 5 times.Â* But I don't need that.

I'm not concerned by the battery capacity, it's the output current
that's the issue here.


That would only matter if you wanted a faster charge - is that what
you're after? If so, yes, you're right, higher current. But IME it
doesn't always work that way - some devices seem to 'choke' the input.

The 5V is the standard voltage for USB and 1A is the maximum rate at
which it can charge your phone. So at 2A the phone will be charged in
half the time it will take at 1A (assuming the phone can take it which
I doubt).

The devices are tablets, some of them (apparently) wont charge at 1A.


I've not heard of that. My iPad charges fine (if slowly) from a 1A
charger. I can't explain why you had issues with the car charger.

The cheap power banks seldom have the claimed capacity but, for
emergency top ups, does it matter that the phone will only be charged
to less than its maximum?

Nope, not a problem, as long as it works I don't care how inefficient it
is. I really am only going to use this as an emergency back up whilst
out during the day, not as a strategy to avoid plugging my tablet in
every evening at the hotel (or at a location where I'm not staying in a
hotel).

I am only concerned that it may not work at all.


It should work. Could you try with a 1A mains charger?


--
Cheers, Rob

charles wrote :
Certainly the case with my iPhone

Iphones can be a bit picky about the sources they are charged from,
mine is and complains, but still recharges slowly.

RJH was thinking very hard :
That would only matter if you wanted a faster charge - is that what you're
after? If so, yes, you're right, higher current. But IME it doesn't always
work that way - some devices seem to 'choke' the input.

Each part, the charger and the thing being charged, defines its own
maximum current - it is the lower of the two figures which defines the
charge level.

On 04/11/2017 20:25, Harry Bloomfield wrote:
charles wrote :
Certainly the case with my iPhone

Iphones can be a bit picky about the sources they are charged from, mine
is and complains, but still recharges slowly.

Very slowly. I think that is a standard Apple marketing ploy, IIRC our
original iPad was similar.

*Apart* from Apple, I think devices will charge at 1A on a 1A charger,
2A on a 2A one (if they are rated for 2A). Just takes twice as long on
the 1A version.

At least we are moving to a civilised world where a high proportion of
devices will charge either off 5V from USB, or 12V. And we have the EU
to thank for phone chargers.

On Sat, 04 Nov 2017 17:32:37 +0000 (GMT), charles wrote:

It's the possibility that a low power output doesn't charge it at
all,
that's the problem

Certainly the case with my iPhone

Apple make products that are "fussy" about what they will consider to
be a suitable energy source for charging. Various combinations of
resistors between the wires an/or ground IIRC.

--
Cheers
Dave.

On Saturday, November 4, 2017 at 2:51:58 PM UTC, tim... wrote:
I have (elsewhere) previous been recommended to buy a power bank to uses as
an emergency back up for my portable devices.

Which, because I have a candy bar phone with a standby time of 3 weeks,
means my tablet and camera.

I was in a shop today, saw one on sale with "for smartphones and tablets" at
a reasonable price and bought it

but after I looked at the back it said output 5V 1A.

Oh!

ISTR that when I bought my in-car USB charger I got one for phones and had
to take it back and get a higher rated one for Tablets. And even then, one
of my tabs reports that it isn't powerful enough to "charge" the device,
though experimentation shows that it does keep it operating for a bit
longer. Plugging my camera in and it doesn't even notice that there's a
charge there.

So I went into all the other shops in the high street to see what they had
(lest I should want to take the purchase back whist I was still there) and
all of them, with one single exception were output 5V 1A, that exception was
fugging expensive and more importantly 3 times the dimensions and 10 times
the weight of the one that I had bought. I particularly wanted a small,
lightweight, fits in your pocket example.

Back home I looked at my plug in the wall USB chargers, which I
(successfully) use interchangeably on all my devices and one says output 5V
2A and the other output 5V 1A.

What's going on here?

what rating do I need to charge my device(s)

I did a quick Google to see if I could find out and found "5 Key Things To
Know When Buying A Power Bank" and one of them is "When you buy a portable
power bank, make sure that it can charge the battery of a specific device"
Yeah, I know that? But how do I find out what that requirement is - I came
here expecting that you were going to tell me as the manufactures of these
devices keep it as secret as the coca cola recipe (I have been online and
downloaded the full specs).

So the item in question is still in its unopened box with all the seals
intact (as it's from one of these shops that aren't the best for taking
stuff back to). do I take it back and seek out a more powerful one, or open
it and try it, and risk the shop refusing my returning it?

tim

There are basically two technologies for delivering faster charge over a USB cable, one which uses a higher current (up to 3A) and Qualcomm Quick Charge which uses a higher voltage (up to 20V). If you don't use the correct one your device won't charge at the faster rate (The devices negotiate the voltage and current so if you plug into the wrong charger nothing should go pop). Also some devices seem fussy about which charger they are plugged in to and will only charge at the faster rate on some chargers for some reason.

If you buy a good powerbank it should support both technologies (Anker is a good brand). They often have separate USB ports for the different technologies.

Philip

On 04/11/2017 14:50, tim... wrote:
I have (elsewhere) previous been recommended to buy a power bank to uses
as an emergency back up for my portable devices.

Which, because I have a candy bar phone with a standby time of 3 weeks,
means my tablet and camera.

I was in a shop today, saw one on sale with "for smartphones and
tablets" at a reasonable price and bought it

but after I looked at the back it said output 5V 1A.

Oh!

ISTR that when I bought my in-car USB charger I got one for phones and
had to take it back and get a higher rated one for Tablets.Â* And even
then, one of my tabs reports that it isn't powerful enough to "charge"
the device, though experimentation shows that it does keep it operating
for a bit longer.Â* Plugging my camera in and it doesn't even notice that
there's a charge there.

So I went into all the other shops in the high street to see what they
had (lest I should want to take the purchase back whist I was still
there) and all of them, with one single exception were output 5V 1A,
that exception was fugging expensive and more importantly 3 times the
dimensions and 10 times the weight of the one that I had bought.Â* I
particularly wanted a small, lightweight, fits in your pocket example.

Back home I looked at my plug in the wall USB chargers, which I
(successfully) use interchangeably on all my devices and one says output
5V 2A and the other output 5V 1A.

What's going on here?

what rating do I need to charge my device(s)

I did a quick Google to see if I could find out and found "5 Key Things
To Know When Buying A Power Bank" and one of them is "When you buy a
portable power bank, make sure that it can charge the battery of a
specific device" Yeah, I know that?Â* But how do I find out what that
requirement is - I came here expecting that you were going to tell me as
the manufactures of these devices keep it as secret as the coca cola
recipe (I have been online and downloaded the full specs).

So the item in question is still in its unopened box with all the seals
intact (as it's from one of these shops that aren't the best for taking
stuff back to).Â* do I take it back and seek out a more powerful one, or
open it and try it, and risk the shop refusing my returning it?

tim



I have a slightly smaller one of these

https://www.amazon.co.uk/ANNKE-10000...nke+power+pack

Mine is 8000 mAh, and will happily jump start a small petrol car with a
completely flat battery. Also has a small torch. Essentially the same
size as my Moto G4, in its flip case.

On Sat, 04 Nov 2017 17:05:34 +0100, Tim Streater wrote:

AFAIK, such sockets are rated at 5V, 1A max - that's the spec.

Orginal USB spec is 5 V +/- 0.25 V and 500 mA max.

This should mean that my iPhone when charging won't draw more than 1A,
but I don't know whether devices are clever enough to "try it on", try
sucking out more than 1A and look for voltage sag, give up if so.

Depends on the source, is it just a 5 V 1 A "power supply" or is it a
5 V 1 A "USB charger" or a 5 V 1 A "USB port" on a laptop/desktop.

My phone refuses to charge from a "power supply" but is quite happy
from a "USB charger" or "USB port". The latter two will have the
required resistors that tell the device what charge rate(s) are
available. A "USB port" will have the resistors but also monitor the
current draw and shut the port down if too much is taken. There may
even be a data conversation to agree power requirements rather than
just rely on the resistors.

--
Cheers
Dave.

On Saturday, November 4, 2017 at 9:39:53 PM UTC, newshound wrote:
On 04/11/2017 14:50, tim... wrote:
I have (elsewhere) previous been recommended to buy a power bank to uses
as an emergency back up for my portable devices.

Which, because I have a candy bar phone with a standby time of 3 weeks,
means my tablet and camera.

I was in a shop today, saw one on sale with "for smartphones and
tablets" at a reasonable price and bought it

but after I looked at the back it said output 5V 1A.

Oh!

ISTR that when I bought my in-car USB charger I got one for phones and
had to take it back and get a higher rated one for Tablets.Â* And even
then, one of my tabs reports that it isn't powerful enough to "charge"
the device, though experimentation shows that it does keep it operating
for a bit longer.Â* Plugging my camera in and it doesn't even notice that
there's a charge there.

So I went into all the other shops in the high street to see what they
had (lest I should want to take the purchase back whist I was still
there) and all of them, with one single exception were output 5V 1A,
that exception was fugging expensive and more importantly 3 times the
dimensions and 10 times the weight of the one that I had bought.Â* I
particularly wanted a small, lightweight, fits in your pocket example.

Back home I looked at my plug in the wall USB chargers, which I
(successfully) use interchangeably on all my devices and one says output
5V 2A and the other output 5V 1A.

What's going on here?

what rating do I need to charge my device(s)

I did a quick Google to see if I could find out and found "5 Key Things
To Know When Buying A Power Bank" and one of them is "When you buy a
portable power bank, make sure that it can charge the battery of a
specific device" Yeah, I know that?Â* But how do I find out what that
requirement is - I came here expecting that you were going to tell me as
the manufactures of these devices keep it as secret as the coca cola
recipe (I have been online and downloaded the full specs).

So the item in question is still in its unopened box with all the seals
intact (as it's from one of these shops that aren't the best for taking
stuff back to).Â* do I take it back and seek out a more powerful one, or
open it and try it, and risk the shop refusing my returning it?

tim



I have a slightly smaller one of these

https://www.amazon.co.uk/ANNKE-10000...nke+power+pack

Mine is 8000 mAh, and will happily jump start a small petrol car with a
completely flat battery. Also has a small torch. Essentially the same
size as my Moto G4, in its flip case.

Doesn't look like it supports Qualcomm Quick Charge though so would charge many phones very slowly (E.g. My G4 gets an 80% charge in 30 minutes with the quick charger). I would be suspicious of that one as the name is a bit too close to a real Anker power bank. Wonder if it actually has an 8000mAH battery in it.

Philip

"tim..." wrote in message
news
I have (elsewhere) previous been recommended to buy a power bank to uses
as an emergency back up for my portable devices.

Which, because I have a candy bar phone with a standby time of 3 weeks,
means my tablet and camera.

I was in a shop today, saw one on sale with "for smartphones and tablets"
at a reasonable price and bought it

but after I looked at the back it said output 5V 1A.


OK guys, I bit the bullet opened the pack and plugged it in

Tablet recognised it is being charged.

Will report back in an hour or two how much progress has been made

tim

On 04/11/2017 16:11, tim... wrote:



It's the possibility that a low power output doesn't charge it at all,
that's the problem


And I think that can only be answered by you with your devices. I have
several portable devices and several chargers. When plugged into a low
amp output device one of them reports on the screen "Charging slowly
please connect to an approved charger" but does eventually charge. A
different device just refuses to charge from the low output device.

Try charging from a standard PC usb output. If its not a USB3 connector
then it should be limited to 500mA. If it will charge off that it will
probably charge off anything.



--
Chris B (News)

On 04/11/2017 21:51, wrote:
On Saturday, November 4, 2017 at 9:39:53 PM UTC, newshound wrote:
On 04/11/2017 14:50, tim... wrote:
I have (elsewhere) previous been recommended to buy a power bank to uses
as an emergency back up for my portable devices.

Which, because I have a candy bar phone with a standby time of 3 weeks,
means my tablet and camera.

I was in a shop today, saw one on sale with "for smartphones and
tablets" at a reasonable price and bought it

but after I looked at the back it said output 5V 1A.

Oh!

ISTR that when I bought my in-car USB charger I got one for phones and
had to take it back and get a higher rated one for Tablets.Â* And even
then, one of my tabs reports that it isn't powerful enough to "charge"
the device, though experimentation shows that it does keep it operating
for a bit longer.Â* Plugging my camera in and it doesn't even notice that
there's a charge there.

So I went into all the other shops in the high street to see what they
had (lest I should want to take the purchase back whist I was still
there) and all of them, with one single exception were output 5V 1A,
that exception was fugging expensive and more importantly 3 times the
dimensions and 10 times the weight of the one that I had bought.Â* I
particularly wanted a small, lightweight, fits in your pocket example.

Back home I looked at my plug in the wall USB chargers, which I
(successfully) use interchangeably on all my devices and one says output
5V 2A and the other output 5V 1A.

What's going on here?

what rating do I need to charge my device(s)

I did a quick Google to see if I could find out and found "5 Key Things
To Know When Buying A Power Bank" and one of them is "When you buy a
portable power bank, make sure that it can charge the battery of a
specific device" Yeah, I know that?Â* But how do I find out what that
requirement is - I came here expecting that you were going to tell me as
the manufactures of these devices keep it as secret as the coca cola
recipe (I have been online and downloaded the full specs).

So the item in question is still in its unopened box with all the seals
intact (as it's from one of these shops that aren't the best for taking
stuff back to).Â* do I take it back and seek out a more powerful one, or
open it and try it, and risk the shop refusing my returning it?

tim



I have a slightly smaller one of these

https://www.amazon.co.uk/ANNKE-10000...nke+power+pack

Mine is 8000 mAh, and will happily jump start a small petrol car with a
completely flat battery. Also has a small torch. Essentially the same
size as my Moto G4, in its flip case.

Doesn't look like it supports Qualcomm Quick Charge though so would charge many phones very slowly (E.g. My G4 gets an 80% charge in 30 minutes with the quick charger). I would be suspicious of that one as the name is a bit too close to a real Anker power bank. Wonder if it actually has an 8000mAH battery in it.

Philip

Reviews generally find they all over-claim capacity a bit. Certainly
this charges my phones happily and as I said will start at least one
car. I guess there are two sorts of users, those who regularly need
reliable fast charging (e.g. sports photographers?) and the rest of us
who get caught short with a flat phone battery once in a while. (I try
to keep a lighter socket and a couple of USB leads in all the vehicles
all the time, but they do seem to wander). I just put my G4 on overnight
on an ordinary charger.

On 05/11/2017 09:58, newshound wrote:

Reviews generally find they all over-claim capacity a bit. Certainly
this charges my phones happily and as I said will start at least one
car. I guess there are two sorts of users, those who regularly need
reliable fast charging (e.g. sports photographers?) and the rest of us
who get caught short with a flat phone battery once in a while. (I try
to keep a lighter socket and a couple of USB leads in all the vehicles
all the time, but they do seem to wander). I just put my G4 on overnight
on an ordinary charger.

They don't over claim capacity.
They quote the capacity of the cell in them.
This is usually a Li-Ion at 3.4 volts(ish) so by the time you have
converted it to 5V you have lost a lot of the capacity if you are
assuming they are 5V cells.
The same applies to jump starters as they aren't likely to have four
cells in series so only have about 10V to play with.

On 04/11/2017 21:33, Dave Liquorice wrote:
On Sat, 04 Nov 2017 17:32:37 +0000 (GMT), charles wrote:

It's the possibility that a low power output doesn't charge it at
all,
that's the problem

Certainly the case with my iPhone

Apple make products that are "fussy" about what they will consider to
be a suitable energy source for charging. Various combinations of
resistors between the wires an/or ground IIRC.


IME it's the cable more than the charger - very fussy about cables.
Anker have been the most consistently reliable non-Apple cables I've used.

--
Cheers, Rob

On 05/11/2017 10:17, dennis@home wrote:
On 05/11/2017 09:58, newshound wrote:

Reviews generally find they all over-claim capacity a bit. Certainly
this charges my phones happily and as I said will start at least one
car. I guess there are two sorts of users, those who regularly need
reliable fast charging (e.g. sports photographers?) and the rest of us
who get caught short with a flat phone battery once in a while. (I try
to keep a lighter socket and a couple of USB leads in all the vehicles
all the time, but they do seem to wander). I just put my G4 on
overnight on an ordinary charger.

They don't over claim capacity.
They quote the capacity of the cell in them.
This is usually a Li-Ion at 3.4 volts(ish) so by the time you have
converted it to 5V you have lost a lot of the capacity if you are
assuming they are 5V cells.
The same applies to jump starters as they aren't likely to have four
cells in series so only have about 10V to play with.
+1 some will claim the mAhr rating of the 3v cell , other smore usefully
the mAhr rating at 5v.
Weight is a good guide to real capacity, as you would expect, weight
correlates very well with capacity.
Some can be charged while providing charge - can be useful .
Higher charge rates often depend on the cable having thick enough
conductors.

"RJH" wrote in message
news
On 04/11/2017 21:33, Dave Liquorice wrote:
On Sat, 04 Nov 2017 17:32:37 +0000 (GMT), charles wrote:

It's the possibility that a low power output doesn't charge it at
all,
that's the problem

Certainly the case with my iPhone

Apple make products that are "fussy" about what they will consider to be
a suitable energy source for charging. Various combinations of resistors
between the wires an/or ground IIRC.

IME it's the cable more than the charger

Yep, Apple doesnt even bother to supply a charger
to use in your car and any of them available work
fine if you use an official lightning cable. They charge
fine from most USB outlets too with the right cable.

- very fussy about cables.

And thats a problem if you want a very
short one to use with a power bank or one
of those combined power bank cases.

Anker have been the most consistently reliable non-Apple cables I've used.

On Saturday, 4 November 2017 15:52:41 UTC, Dave Plowman (News) wrote:
In article ,
tim... wrote:
ISTR that when I bought my in-car USB charger I got one for phones and had
to take it back and get a higher rated one for Tablets. And even then, one
of my tabs reports that it isn't powerful enough to "charge" the device,
though experimentation shows that it does keep it operating for a bit
longer. Plugging my camera in and it doesn't even notice that there's a
charge there.

Do all those devices have a 'standard' USB 5v charger as supplied? None of
my laptops etc do.

I thought all laptops came with a charger, thing is they areblt 5V closer to 20V IIRC.


I wonder how long a car would take to charge from a USB port ;-)

On 06/11/2017 16:23, whisky-dave wrote:
On Saturday, 4 November 2017 15:52:41 UTC, Dave Plowman (News) wrote:
In article ,
tim... wrote:
ISTR that when I bought my in-car USB charger I got one for phones and had
to take it back and get a higher rated one for Tablets. And even then, one
of my tabs reports that it isn't powerful enough to "charge" the device,
though experimentation shows that it does keep it operating for a bit
longer. Plugging my camera in and it doesn't even notice that there's a
charge there.

Do all those devices have a 'standard' USB 5v charger as supplied? None of
my laptops etc do.

I thought all laptops came with a charger, thing is they areblt 5V closer to 20V IIRC.

The wife's laptop/tablet charges from USB.
Its linx 1010 IIRC.

OK guys, I bit the bullet opened the pack and plugged it in

Tablet recognised it is being charged.

Will report back in an hour or two how much progress has been made

tim

Depends if the tablet's off or on. Even iPads will charge slowly if switched off, even on 1A, but slowly. If it's in use it will still run its battery down unless you have 2.1A or more.
No doubt someone will correct me.

"therustyone" wrote in message
...


OK guys, I bit the bullet opened the pack and plugged it in

Tablet recognised it is being charged.

Will report back in an hour or two how much progress has been made

tim

Depends if the tablet's off or on. Even iPads will charge slowly if
switched off, even on 1A, but slowly. If it's in use it will still run
its battery down unless you have 2.1A or more.
No doubt someone will correct me.

took longer to test than I thought as it wasn't (as promised on the pack)
fully charged and ready to go.

It takes 3 hours to fully charge,

with

Tab1 it only managed to half change the device before it ran out of juice,
but that took less than an hour.

Tab 2 (the Hudl that has given me all the previous charger grief) was
already on 95% but it took over half an hour to get to 100% - I suspect that
is the fault of the Hudl.

Plugged it into sister's iPhone and it went to 80% in an hour.

All in all, could be better but for 9.99, I'm happy - it serves the purpose
it is intended for.

(brand is ChargeWorx if anyone's interested, bought it in "Game")

tim

tim... wrote:

took longer to test than I thought as it wasn't (as promised on the pack)
fully charged and ready to go.

This is a handy little gadget that could help to understand what
is going on

https://www.ebay.co.uk/itm/Muker-J7-USB-MultiMeter-Compatible-with-QC2-0-QC3-0-Test-Current-A-Voltage-V-Wh-/253084677818

Following a mention in PC Pro, I picked mine up cheaper on
Amazon, but it seems to have vanished now.

This video shows off its abilities:

https://www.youtube.com/watch?v=QIHQ33EvQyQ

Chris
--
Chris J Dixon Nottingham UK


Plant amazing Acers.

On Tue, 07 Nov 2017 08:46:50 +0000
Chris J Dixon wrote:

tim... wrote:

took longer to test than I thought as it wasn't (as promised on the
pack) fully charged and ready to go.

This is a handy little gadget that could help to understand what
is going ondummy

https://www.ebay.co.uk/itm/Muker-J7-USB-MultiMeter-Compatible-with-QC2-0-QC3-0-Test-Current-A-Voltage-V-Wh-/253084677818

Following a mention in PC Pro, I picked mine up cheaper on
Amazon, but it seems to have vanished now.

Just search eBay for "USB doctor 30v" - they're £4-£6 from China.

This video shows off its abilities:

https://www.youtube.com/watch?v=QIHQ33EvQyQ

I still have a 2nd gen one (the pale blue one) that cost £3 a few years
ago. No need for fast charge capability here yet. What is handy is a
dummy test load so you can check the stability of a supply without
plugging in any electronic devices.

On 04/11/2017 14:50, tim... wrote:

I have (elsewhere) previous been recommended to buy a power bank to uses
as an emergency back up for my portable devices.

It is useful to have one to extend the usable life of portable devices
when away from mains power or when the mains fails.

I have a solar powered one too which is good in the wilds.

Which, because I have a candy bar phone with a standby time of 3 weeks,
means my tablet and camera.

I was in a shop today, saw one on sale with "for smartphones and
tablets" at a reasonable price and bought it

but after I looked at the back it said output 5V 1A.

Oh!

Most of the smaller ones are. It will charge a tablet that is switched
off but it will only delay the discharge of the devices internal battery
if it is active (think of it as extra Ah of add-on battery power).

ISTR that when I bought my in-car USB charger I got one for phones and
had to take it back and get a higher rated one for Tablets.Â* And even
then, one of my tabs reports that it isn't powerful enough to "charge"
the device, though experimentation shows that it does keep it operating
for a bit longer.Â* Plugging my camera in and it doesn't even notice that
there's a charge there.

The latter may indicate that you are using the wrong lead.

So I went into all the other shops in the high street to see what they
had (lest I should want to take the purchase back whist I was still
there) and all of them, with one single exception were output 5V 1A,
that exception was fugging expensive and more importantly 3 times the
dimensions and 10 times the weight of the one that I had bought.Â* I
particularly wanted a small, lightweight, fits in your pocket example.

There is nothing wrong with a 1A output - you just have to accept that
it cannot recharge devices that are drawing more current than it can
supply. It still acts as a power source whilst connected to the device.
That is it slows down the rate of discharge of the internal battery.

Back home I looked at my plug in the wall USB chargers, which I
(successfully) use interchangeably on all my devices and one says output
5V 2A and the other output 5V 1A.

What's going on here?

what rating do I need to charge my device(s)

Think of it more like extending their useful time on power.
So the item in question is still in its unopened box with all the seals
intact (as it's from one of these shops that aren't the best for taking
stuff back to).Â* do I take it back and seek out a more powerful one, or
open it and try it, and risk the shop refusing my returning it?
Why did you get a power bank in the first place?

Most of mine were giveaways in goody bags at various conferences along
with smaller USB memory sticks and promotional DVDs. There is no free
lunch - a 2A output needs a bigger heavier battery to be worthwhile.

It is a tradeoff of convenience and having the thing available in an
emergency vs carrying a large power brick around on the off chance.

FWIW I find I use a USB adapter in the cars cigarette lighter more often
and it can supply a full power 2.4A charge rate on two sockets.

--
Regards,
Martin Brown

On Monday, 6 November 2017 16:43:17 UTC, dennis@home wrote:
On 06/11/2017 16:23, whisky-dave wrote:
On Saturday, 4 November 2017 15:52:41 UTC, Dave Plowman (News) wrote:
In article ,
tim... wrote:
ISTR that when I bought my in-car USB charger I got one for phones and had
to take it back and get a higher rated one for Tablets. And even then, one
of my tabs reports that it isn't powerful enough to "charge" the device,
though experimentation shows that it does keep it operating for a bit
longer. Plugging my camera in and it doesn't even notice that there's a
charge there.

Do all those devices have a 'standard' USB 5v charger as supplied? None of
my laptops etc do.

I thought all laptops came with a charger, thing is they areblt 5V closer to 20V IIRC.

The wife's laptop/tablet charges from USB.
Its linx 1010 IIRC.

The linx is a tablet not a laptop, there's a differnce.

"Martin Brown" wrote in message
news
On 04/11/2017 14:50, tim... wrote:

I have (elsewhere) previous been recommended to buy a power bank to uses
as an emergency back up for my portable devices.

It is useful to have one to extend the usable life of portable devices
when away from mains power or when the mains fails.

I have a solar powered one too which is good in the wilds.

Which, because I have a candy bar phone with a standby time of 3 weeks,
means my tablet and camera.

I was in a shop today, saw one on sale with "for smartphones and tablets"
at a reasonable price and bought it

but after I looked at the back it said output 5V 1A.

Oh!

Most of the smaller ones are. It will charge a tablet that is switched off
but it will only delay the discharge of the devices internal battery if it
is active (think of it as extra Ah of add-on battery power).

ISTR that when I bought my in-car USB charger I got one for phones and
had to take it back and get a higher rated one for Tablets. And even
then, one of my tabs reports that it isn't powerful enough to "charge"
the device, though experimentation shows that it does keep it operating
for a bit longer. Plugging my camera in and it doesn't even notice that
there's a charge there.

The latter may indicate that you are using the wrong lead.

It's the same lead whatever power source I use

tim

"Martin Brown" wrote in message
news
On 04/11/2017 14:50, tim... wrote:

I have (elsewhere) previous been recommended to buy a power bank to uses
as an emergency back up for my portable devices.

It is useful to have one to extend the usable life of portable devices
when away from mains power or when the mains fails.

I have a solar powered one too which is good in the wilds.

Which, because I have a candy bar phone with a standby time of 3 weeks,
means my tablet and camera.

I was in a shop today, saw one on sale with "for smartphones and tablets"
at a reasonable price and bought it

but after I looked at the back it said output 5V 1A.

Oh!

Most of the smaller ones are. It will charge a tablet that is switched off
but it will only delay the discharge of the devices internal battery if it
is active (think of it as extra Ah of add-on battery power).

ISTR that when I bought my in-car USB charger I got one for phones and
had to take it back and get a higher rated one for Tablets. And even
then, one of my tabs reports that it isn't powerful enough to "charge"
the device, though experimentation shows that it does keep it operating
for a bit longer. Plugging my camera in and it doesn't even notice that
there's a charge there.

The latter may indicate that you are using the wrong lead.

So I went into all the other shops in the high street to see what they
had (lest I should want to take the purchase back whist I was still
there) and all of them, with one single exception were output 5V 1A, that
exception was fugging expensive and more importantly 3 times the
dimensions and 10 times the weight of the one that I had bought. I
particularly wanted a small, lightweight, fits in your pocket example.

There is nothing wrong with a 1A output - you just have to accept that it
cannot recharge devices that are drawing more current than it can supply.
It still acts as a power source whilst connected to the device. That is it
slows down the rate of discharge of the internal battery.

Back home I looked at my plug in the wall USB chargers, which I
(successfully) use interchangeably on all my devices and one says output
5V 2A and the other output 5V 1A.

What's going on here?

what rating do I need to charge my device(s)

Think of it more like extending their useful time on power.
So the item in question is still in its unopened box with all the seals
intact (as it's from one of these shops that aren't the best for taking
stuff back to). do I take it back and seek out a more powerful one, or
open it and try it, and risk the shop refusing my returning it?
Why did you get a power bank in the first place?

because I don't have an employer playing 500 pounds a time for me to attend
a conference


Most of mine were giveaways in goody bags at various conferences along
with smaller USB memory sticks and promotional DVDs. There is no free
lunch - a 2A output needs a bigger heavier battery to be worthwhile.

It is a tradeoff of convenience and having the thing available in an
emergency vs carrying a large power brick around on the off chance.

FWIW I find I use a USB adapter in the cars cigarette lighter more often
and it can supply a full power 2.4A charge rate on two sockets.

--
Regards,
Martin Brown