Adjusting the power from 100 to 10mW on the wireless, saves battery???
 

Hi There All,

I read this somewhere
Adjusting the power from 100 to 10mW on the wireless, saves battery
Settings- Internet connections - connections - "Edit one of your connections"- Click Next 3 times . click Advanced - Other

Bu wanted to see if any of you guys know

1) is it worth it - does it save much battery power

2) What will the trade off be ... whats the negative point of it? lower speed connection?

Cheers

Re: Adjusting the power from 100 to 10mW on the wireless, saves battery???
 

Per Conky, I'm still connected at between 36-48Mbs, and have no problems browsing in my basement, while router is on top floor of my house. I can go ~24hrs between charges with WiFi "on" the whole time, in 10mW mode.

No discernable lag, nor QoS issues using SIP client, connecting to a personal router, and then ISP provided router, before hitting internet...this coming from a VoIP engineer.

Re: Adjusting the power from 100 to 10mW on the wireless, saves battery???
 

1) Depends on wifi usage. Could be quite a lot.
2) Shorter range.

And, some issues on select APs.

Re: Adjusting the power from 100 to 10mW on the wireless, saves battery???
 

Not shorter, VERY short, as matter fact 10 times shorter, I'd advise you not to.

Re: Adjusting the power from 100 to 10mW on the wireless, saves battery???
 

Would be very nice if the wifi power options were specifiable per access point instead of globally.

Some routers/locations work great with things turned down, others not so much.

Re: Adjusting the power from 100 to 10mW on the wireless, saves battery???
 

What?

:confused:

Re: Adjusting the power from 100 to 10mW on the wireless, saves battery???
 

I live in a flat with more than 100m² and I keep the WiFi setting at 10 and I can do everything with it no problemo...

Unless your bathroom is bullet proof or, worse, there is not bathroom and you need to go far away to find some bushes I think you will be fine...

And yes, it saves some battery.

Re: Adjusting the power from 100 to 10mW on the wireless, saves battery???
 

not that i could notice, and got significant connection quality drawbacks, so i switched back to 100.

Re: Adjusting the power from 100 to 10mW on the wireless, saves battery???
 

A lot of that is dependent on your router, and the composition of your home.

I've been on 10mW since I've had my 900, and in my townhouse development (my house its the "A" ballon :) ), I pick up no less than 10 WLANs:

http://home.comcast.net/~masterpiu/crib.JPG


...draw your own conclusions about which homes actually have wireless routers, but either way you look at it, picking up (10) on my street, pushes the connection radius out pretty far for the "low power setting".

Re: Adjusting the power from 100 to 10mW on the wireless, saves battery???
 

My backyard is bigger than your backyard

;-)

Re: Adjusting the power from 100 to 10mW on the wireless, saves battery???
 

Nope.

A drop from 100mW to 10mW is a 10dB cut.

6dB less signal will reduce your range by 50%. 12dB less will reduce it to 25% of the initial range. So a 10dB cut will give slightly greater than 25% of the initial range.

If you could get 100m with 100mW, expect 25 to 30m with 10mW.

Re: Adjusting the power from 100 to 10mW on the wireless, saves battery???
 

I've come to accept, a long time ago, that their are a lot of people that have, and will always have, bigger backyards than I do. Irregardless of how well my investments may ever do, I can live with the fact that I'll never have a home with a golden toilet, people working there whose sole purpose is to guide vistors in case they get lost, nor silverware which is thrown away after initial use.

But I find much comfort in the fact that I own both a tube amp, and an steel Italian bicycle.

:)

Re: Adjusting the power from 100 to 10mW on the wireless, saves battery???
 

no way! you have a steel itallian bicycle .... niiiiiice!

Re: Adjusting the power from 100 to 10mW on the wireless, saves battery???
 

"Its in the name"...lol, I think so. I'm old school and afraid of carbon...and can't get with oversized tubes...but I digress.

:p

Re: Adjusting the power from 100 to 10mW on the wireless, saves battery???
 

This feature is mandatory for WiFi certification. It is not designed to save power and it should not be changed from the default (100 mW). http://talk.maemo.org/showpost.php?p=1838&postcount=10 Times have not changed much from 2005 in this sense ;)

/thread

Re: Adjusting the power from 100 to 10mW on the wireless, saves battery???
 

Indeed. It might just cause more retransmissions if the signal is weak, or, cause the link to reduce speed in order to increase the energy per bit.

Re: Adjusting the power from 100 to 10mW on the wireless, saves battery???
 

I did a run round the main places i use my N900 in the house to test the quality (using Conky) once using 10mW and once using 100mW.
Here are the results

..........................100mW..........10mW
next to pc............100%..........100%
kitchen................63%..............60%
bedroom.............55%..............58%
toilet :D:D............41%.............43%

so from that there is no difference to the quality on 10mW or 100mW it just depends on the question .... what extra battery time do you get:confused:.
Maybe i should fully charge the battery, stream in video on 100mW and see how long it takes till the battery dies then recharge and retry on 10mW:eek:

Re: Adjusting the power from 100 to 10mW on the wireless, saves battery???
 

so, as you can switch back to the original value, the question is simple:

does it save battery-life or does it not?

[_] yes
[_] no

;)

Re: Adjusting the power from 100 to 10mW on the wireless, saves battery???
 

At idle, with no widgets, save for calendar and weather, and (3) POP3 email clients polling every hour, I can go about 24 hours per charge, given an hour or two of "use", with 10mW active "all day".

Re: Adjusting the power from 100 to 10mW on the wireless, saves battery???
 

My Back yard is bigger than your whole neighborhood. :D

Sorry. Couldn't help myself. Just had to get into this "my back yard is bigger than yours" contest. LMAO

/hijack

Re: Adjusting the power from 100 to 10mW on the wireless, saves battery???
 

You are measuring the received signal strength on the N900. That's pretty irrelevant. You need to look at the 'Rate' in conky, to see if that drops. With the lower power output, the wifi link will drop to a lower rate in some places as the signal received by the access point will drop below the signal to noise ratio required to sustain the higher rate.

Also, IIRC, with a lower tx power from the N900, the access point may well increase its power, if it assumes that the connection is symmetric, so that could also affect the Connection Quality reported by Conky.

Re: Adjusting the power from 100 to 10mW on the wireless, saves battery???
 

i initially did write down the Mb/s at each point but i found the figure would change constantly on both 10mW and 100mW ..... maybe when the wifi was being used or something.

related:
http://m.mippin.com/mip/plus/story.j...63329528013136
http://talk.maemo.org/showthread.php?t=36444

I dunno ... i might just leave it on 100mW and buy a spare battery!!!!!
lol

Re: Adjusting the power from 100 to 10mW on the wireless, saves battery???
 

The issue you describe is bug #2821 which is going to be fixed in Harmattan.

Also comment #6 from that bug is relevant:

This setting makes no real difference in terms of power consumption, it's mainly a regulatory issue but may improve the stability of a weak WiFi connection.

Re: Adjusting the power from 100 to 10mW on the wireless, saves battery???
 

Yeah, townhouses "typically" do not have "ponderosas" and "mesas" as backyards.

:p

Re: Adjusting the power from 100 to 10mW on the wireless, saves battery???
 

On 100mw my n900 drained battery seriously fast (by this i mean.. atleast 50% battery in 1 hour), on 10mw i'm able to be connected pretty much a hole day, and surf for hours.

maybe my router causes the huge power consumption on 100mw, maybe not. One thing is 100% for sure, 100mw kills my battery.. faaast on my home router.

I can still reach max speed on my 20mbit adsl at home even though i'm only using 10mw setting.

Re: Adjusting the power from 100 to 10mW on the wireless, saves battery???
 

I noticed that as a rule by the time the 10 mW is insufficient I'm almost out of range with the recv. The actual range cut is not that dramatic, due to limited receiving antenna. Might be my local setup/noise, but that's how it works in practice here.

Re: Adjusting the power from 100 to 10mW on the wireless, saves battery???
 

The wifi antenna should, in theory [Note: see my sig :) ], and assuming that the same antenna is used for transmission and reception, perform equally well (or badly) for transmission and reception. There may be other issues making the connection asymmetric, e.g. noise levels.

Sorry if i seem like I'm being pedantic.

Re: Adjusting the power from 100 to 10mW on the wireless, saves battery???
 

Does. It. Save. Battery?

That is the question no one is directly answering.

Re: Adjusting the power from 100 to 10mW on the wireless, saves battery???
 

Yes. You're transmitting using 1/10th of the power, thus you will save battery power.

However, of far greater impact are the powersave modes. Sadly, I can't use these with my router at home and as a result even at 10mW my battery is sapped quickly if I leave it on WiFi (as compared to 2.5G) at work where the routers are better I get about 3/4 a day (music, constant data traffic) with wifi on.

Re: Adjusting the power from 100 to 10mW on the wireless, saves battery???
 

Guys, 10mW or 100mW is a MAXIMUM power.

It means, that if you have a good reception then N900 will not reach 100mW but works on less power (if powersaving is ON, of course).

If you haven't good reception - you need 100mW max, right?

BTW, this parameter is for legal reason only - some countries limit the max output.

Re: Adjusting the power from 100 to 10mW on the wireless, saves battery???
 

That would actually be a good test

Apple Itouch is approx 7 hours streaming full screen video (barring the buffer issues it has :D)

but a comparative test would be to stream the video to an n900 with the cellular disabled, but then the n900 on the latest firmware cant stream upnp video now can it

I *may* try it tomorrow as im doing wireless training for the next 2 days so an ideal environment :D

Re: Adjusting the power from 100 to 10mW on the wireless, saves battery???
 

You can't compare it to any other hardware, too many things are different, screen, brightness, content, format, etc etc. Still :)

Re: Adjusting the power from 100 to 10mW on the wireless, saves battery???
 

I know, but it would be an interesting test nonetheless

I install large scale wireless for a living and we have just rolled out 900 Itouches to one place and they have a couple of niggling issues which appear to be buffer related but you cannot change anything at all on the itouches :D

Occasionally though we get to recommend the wireless devices the customers want :)

Re: Adjusting the power from 100 to 10mW on the wireless, saves battery???
 

When I tested on n810 and n800 I could not measure any difference in power consumption. Theoretically 100mW is about 37mA. The n800 and n810 consume about 350mA streaming audio over wifi. So the radiated power by wifi is about 10 percent of total power use. I guess a 9 percent gain is worth something, but not much compared to range reduction.

Re: Adjusting the power from 100 to 10mW on the wireless, saves battery???
 

maybe it is strange but when I change 100mW to 10mW i cant see any skype contacts online and when I change it to 100mW everything is ok again.

Re: Adjusting the power from 100 to 10mW on the wireless, saves battery???
 

I can seee mine, i recently shifted this mode as all my battery was being drained out by the Wi-fi..