Need help with Battery mAH & AH questions ??

g4fne

Hi folks ... I'm after a bit of advice on battery & power ratings.

I have recently purchased this handheld TV http://www.amazon.co.uk/MPman-Pocket-Digital-Freeview-Control/dp/B000JSCBI2/ref=pd_bbs_sr_1/202-1709952-9815067?ie=UTF8&s=electronics&qid=1186875063&sr=8-1

The TV comes with a built in 3.7V/2000mAH rechargeable polymer battery which is not removeable & is supposed to offer 3hours of usage.

I need to increase the useage & have no access to mains so have purchased a power station as below.


The power station has a built in "built in sealed lead-acid maintanance free rechargeable battery. DC12V, 7AH, or 12V 4AH"



I have three questions

1) What is the difference between DC12V, 7AH & 12V 4AH ??

2) Which rating from question 1 is relevant to running or charging the TV

3) Can anyone confirm for me, that if 2000mAH rechargeable battery thats built into the TV gives 3 hours of power, then would a 4AH battery offer double the power (ie ... 6 hours of use) ?? ... (i'm assuming 4AH is equivalent to 4000mAH ??)


Any advice would be appreciated folks

ollyk

Yes 4Ah is the same as 4000mAh this is stating that if a load draws 4A then the battery will be discharged in 1 hour OR if battery draws 1A then it will discharge within 4 hours.

Now I assume you have a 12V DC input to the portable telly and a suitable lead with the correct polarity? Depeding how the telly handles the external power supply will determine how quickly the external battery is drained.

g4fne wrote: »

Hi folks ... I'm after a bit of advice on battery & power ratings.

I have recently purchased this handheld TV http://www.amazon.co.uk/MPman-Pocket-Digital-Freeview-Control/dp/B000JSCBI2/ref=pd_bbs_sr_1/202-1709952-9815067?ie=UTF8&s=electronics&qid=1186875063&sr=8-1

The TV comes with a built in 3.7V/2000mAH rechargeable polymer battery which is not removeable & is supposed to offer 3hours of usage.

I need to increase the useage & have no access to mains so have purchased a power station as below.


The power station has a built in "built in sealed lead-acid maintanance free rechargeable battery. DC12V, 7AH, or 12V 4AH"



I have three questions

1) What is the difference between DC12V, 7AH & 12V 4AH ??

2) Which rating from question 1 is relevant to running or charging the TV

3) Can anyone confirm for me, that if 2000mAH rechargeable battery thats built into the TV gives 3 hours of power, then would a 4AH battery offer double the power (ie ... 6 hours of use) ?? ... (i'm assuming 4AH is equivalent to 4000mAH ??)


Any advice would be appreciated folks

davetrousers

Holy Cow OllyK, with the OP being so large with the 2 pics, is it really necessary to quote the whole of the OP in your response?

espresso

:doh:

Surly a radio amateur should not be asking such elementary questions like this! or are you a pirate?

1. The power station cannot be both 12V 7Ah and 12V 4Ah, so I would guess that there are two variations made, containing different capacity batteries but the label covers both variations.

2. You could only use this power station to charge the TV's battery unless the TV has a separate 12V DC input socket.

3. Read the reviews on the Amazon site.

P.S. Ollyk There was no need to quote any of the original post!

g4fne

Thanks Ollyk for your response & confirming that 4AH is equivalent to
4000 mAH & yes i did get a 12V DC input come with the TV :beer:



Hi Expresso ... Perhaps i'm being a little slow this Sunday morning but you've lost me mate on these responses of yours

"Surly a radio amateur should not be asking such elementary questions like this! or are you a pirate?"
What does this mean ?????


"Read the reviews on the Amazon site"
I gave the weblink to the Amazon site on my original post ... Of course i've read the reviews .... Where on the reviews does it answer my questions ?????

Conor_3

g4fne wrote: »

"Surly a radio amateur should not be asking such elementary questions like this! or are you a pirate?"
What does this mean ?????

Your forum name, g4fne is the same format as the callsigns Radio Amateurs are issued. Once upon a time, a Radio Ham had to have a rudimentary understanding of electronics - something which would have meant you could have answered your own question.

g4fne

Oh i see ..... That explains why it went right over my head then

espresso

g4fne wrote: »

Hi Expresso ... Perhaps i'm being a little slow this Sunday morning but you've lost me mate on these responses of yours

"Surly a radio amateur should not be asking such elementary questions like this! or are you a pirate?"
What does this mean ?????

Thanks to Conor for the explanation, apologies if you are not a radio ham!

g4fne wrote: »

"Read the reviews on the Amazon site"
I gave the weblink to the Amazon site on my original post ... Of course i've read the reviews .... Where on the reviews does it answer my questions ?????

Well doesn't this help for question 3?

Either way, this little TV has fared extremely well for me and not having had problems with lack of signal, can't knock any stars off a perfect score. The picture is pretty much perfect (even easily watchable outside during sunny days), news tickers can also be read clearly and believe it or not, you can see the ball when watching golf! (Not a golf fan btw, just pointing out the quality. A final worthwhile example is the kids have been able to watch CITV/Cbeebies etc in the car on the way back from school with no loss of picture at all! (A trip of about 8 miles). The sound is loud enough despite the tiny built in speaker, it fits in my shirt pocket and weighs about the same as my mobile phone. Battery at full volume lasts me about 3 hours, charges in less than 1 hour. 40+ TV channels and digital radio in a unit slightly larger than a pack of cards: I for one am impressed. Just as importantly, my mates are too:-) I can't knock its performance in and around Surrey and Hampshire though I'd assume there are places it won't work, (just as with handheld analogue TV) I just haven't found any yet. A worthy 5 stars.

g4fne

Without wishing to come across pedantic, i was aware as stated in my original post "The TV comes with a built in 3.7V/2000mAH rechargeable polymer battery which is not removeable & is supposed to offer 3hours of usage."

What i needed confirming was if 4AH is same as 4000mAH ... ie double the power of the built in 2000mAH .... Which OllyK answered in his post.

espresso

"Without wishing to come across pedantic", ollyk didn't answer questions 1 & 2 did he?

Are you a radio ham then or not?

g4fne

espresso wrote: »

Are you a radio ham then or not?

Nope ... never in my life