Random XDA musings, part 3

[Jason Dunn]

I took my XDA with me when I went away for a short trip outside Calgary this weekend, and I was outside the GSM coverage while there. I manually turned off the phone software, so it was no longer seeking a signal. On the Sunday morning when we were leaving, I turned it back on - still no signal, but I figured it would pick it back up when it came within range.<br /><br />What I didn't realize, however, was that the XDA polls for signal every 15 seconds, and when it's seeking a signal it goes into a "high powered" mode to get a lock. When it can't find a lock, it gives up, and tries again in 15 seconds. As you might imagine, this has a brutal effect on battery life. I've been thrilled with the battery life of the XDA so far, but if you're going outside a GSM-covered area, turn off the phone software to prevent a serious drain on your battery. I wish this polling time was user-configurable - I'd rather have it set to poll every 10 minutes or so.

[Master O'Mayhem]

Also Turn your phone off on flights!!! You dont need it and if you leave it on, the battery will drain... Who said you cant turn off the phone? Was it Walt Mossberg? hmmm ..... the naivite of the uninformed.....

[sweetpete]

I wish this polling time was user-configurable - I'd rather have it set to poll every 10 minutes or so.

Don't quote me on this Jason, but I believe that is a GSM standard for the phone to try and reacquire signal every 15 seconds. It's definitely horrible on the battery drain, but the intent is to keep you communicated.

The reason this isn't an issue elsewhere is that Europe and other countries have vastly higher GSM coverage (i.e. most countries are totally covered in and around urban areas) and therefore signal loss is infrequent (i.e. due to lack of indoor or underground coverage). Curious to know if you tested to see if Rogers had coverage in the areas that Microcell didn't once you left the city?? In BC, Rogers has a larger GSM footprint, but I find the quality of calls with my Fido/Microcell phones is significantly higher within the same coverage area.

[Marc Zimmermann]

Also Turn your phone off on flights!!! You dont need it and if you leave it on, the battery will drain...
Actually, you MUST turn it off. There are many countries where it is a criminal offence to use radio devices on airplanes. The reason behind this is that the radio waves are being reflected by the plane shell and it is believed to affect the reliability of sensitive aircraft electronics.

[SiliconAddict]

Luckily you can switch the phone off (or on) easily by pressing and holding the red phone key for some 3 seconds. :idea:

[denivan]

I can see this would be a big problem in the US. As far as I've heard most carriers haven't been very enthousiastic over GSM and haven't been investing the necessary effort in optimizing the GSM network overthere. Europe has excellent coverage though, my country (Belgium) for instance has 98% coverage so I can say that I will never notice the effect of fast battery drainage due to a weak signal. What could you do? E-mail your network provider and ask them to invest more in the GSM standard.

[GregWard]

I think there's something else as well. As I understand it the battery life on any GSM/GPRS device is dependant on the strength of the signal. If you stand next to a cell the device spends very little energy reporting it's presence (it, obviously, has to do this regularly so that the "system" knows where to find you if somebody tries to ring). On the other hand if you are "on the edge" of coverage it needs to boost it's signal strength and battery life falls sharply.

I'm not an expert but this, at any rate, is the "excuse" given by the Phone Mags as to why claimed battery life differs (substantially) from "real world" tests.

From practical experience I can certainly say that two years ago my phone used to last a fraction of the time when we were at our cottage in Cornwall (remote part of the country) as compared to our main home in London. Now the situation is reversed. Why? They put a new cell in the field behind the cottage!!!!

ps The other benefit is that we can buy pre-microwaved sheep! :lol:

[sweetpete]

Also Turn your phone off on flights!!! You dont need it and if you leave it on, the battery will drain...
Actually, you MUST turn it off. There are many countries where it is a criminal offence to use radio devices on airplanes. The reason behind this is that the radio waves are being reflected by the plane shell and it is believed to affect the reliability of sensitive aircraft electronics.

Sorry, but that is a load of BS :roll: There have been many studies looking at the use of cell phones in airplanes and not one has shown any interference with the so-called sensitive aircraft electronics

Not to change the topic, but that is just bologna fed by the airline industry to keep you using the air phones at $6/min (a cut of which they happily take from GTE and AT&T). The FAA doesn't actually ban cell phone use, only the FCC, and that ban was unrelated to airplane interfernce. It had to do with these calls interfereing with ground cell phone calls.
Both Boeing and Airbus have tested this thoroughly and the FAA itself also reviewed flight data and no evidence was found.

[vikasmg]

Is the ability and method of switching off the phone in a Pocket PC Phone eddition machine specific to the brand or generic to Phone edition Pocket PCs. I'm about to buy an HP Jornada 928 in a day or two (becomes available here in Singapore sometime in the next couple of days) this week and have been worrying about turning the phone off on planes since I read in PC magazine that it couldn't be done on the T-mobile (or whatever the O2 XDA is called in North America).

TIA

- Vikas

I took my XDA with me when I went away for a short trip outside Calgary this weekend, and I was outside the GSM coverage while there. I manually turned off the phone software, so it was no longer seeking a signal. On the Sunday morning when we were leaving, I turned it back on - still no signal, but I figured it would pick it back up when it came within range.....

[sweetpete]

Is the ability and method of switching off the phone in a Pocket PC Phone eddition machine specific to the brand or generic to Phone edition Pocket PCs. I'm about to buy an HP Jornada 928 in a day or two (becomes available here in Singapore sometime in the next couple of days) this week and have been worrying about turning the phone off on planes since I read in PC magazine that it couldn't be done on the T-mobile (or whatever the O2 XDA is called in North America).

TIA

- Vikas

I took my XDA with me when I went away for a short trip outside Calgary this weekend, and I was outside the GSM coverage while there. I manually turned off the phone software, so it was no longer seeking a signal. On the Sunday morning when we were leaving, I turned it back on - still no signal, but I figured it would pick it back up when it came within range.....

All of these devices have the ability to turn off the radio including the T-Mobile XDA.

[Marc Zimmermann]

Sorry, but that is a load of BS :roll: There have been many studies looking at the use of cell phones in airplanes and not one has shown any interference with the so-called sensitive aircraft electronics
Still, it is banned or prohibited in many countries, including the USA. There is no 100% definite evidence, but there's also no evidence that it doesn't cause any interference.
Not to change the topic, but that is just bologna fed by the airline industry to keep you using the air phones at $6/min (a cut of which they happily take from GTE and AT&T).
Cell phones won't work in-flight, anyway, except for take-off and landing where the aircraft is not too high. GSM phones will increase their signal in order to try to reach their base stations but that will not work if the plane gets too high.

[DrtyBlvd]

Thought - How did the people on the September 11th flights make the calls heard on the news? I recall them saying they had used their mobiles - and was surprised they had worked?

[Arne Hess]

Cell phones won't work in-flight, anyway, except for take-off and landing where the aircraft is not too high. GSM phones will increase their signal in order to try to reach their base stations but that will not work if the plane gets too high.
BTW: GSM has speedlimits! :-) No joke! As higher the used frequency band is as lower is the speedlimit!
While it is something around 400 km/h for GSM 900 it's something around 250 km/h (if I remember right for both) for GSM 1800 and even lower for GSM 1900!
And yes, like Marc said, GSM doesn't works in the sky because the BTS are designed to cover the ground, not the sky. You even have this problem on skyscrapers! (Best example is the Empire State Building where is near no coverage on the top while you have full coverage on the ground).
While BTS could work up to 35 km distance it could be possible to cover the sky too with GSM but this isn't implemented today.

[Arne Hess]

Thought - How did the people on the September 11th flights make the calls heard on the news? I recall them saying they had used their mobiles - and was surprised they had worked?
Sorry to say but personally I don't believe this stories. Maybe they used the sky phones or the analogue cell phone systems in the US works in the sky but not GSM!

[Arne Hess]

All of these devices have the ability to turn off the radio including the T-Mobile XDA.
The is no T-Mobile "xda" :wink:

Here the product names for the different brand names:
* T-Mobile Germany: MDA (Mobile Digital Assistant)
* o2 Europe: xda (Extended Digital Assistant)[/list]
* T-Mobile US: Pocket PC Phone Edition (no special device name)

[Marc Zimmermann]

Thought - How did the people on the September 11th flights make the calls heard on the news? I recall them saying they had used their mobiles - and was surprised they had worked?
If they really used their cell phones, they only could have done so because the planes were flying low.

[Venturello]

Would reaaaally like it if there was a registry setting somewhere for this 15s timing. Has anyone searched? Though I could also reason this was embedded into the hardware of the phone side of the device....

[Arne Hess]

Would reaaaally like it if there was a registry setting somewhere for this 15s timing. Has anyone searched? Though I could also reason this was embedded into the hardware of the phone side of the device....
1st: It's in the GSM/GPRS stack of the radio so there is no Registry entry available...
2nd: Changing it doesn't makes sense. For example if you would change it to let's say 10 minutes and you would drive though a tunnel where you lose the GSM connection, you would be offline for the next 10 minutes because your mobile phone doesn't scan for network coverage the next x minutes...

If you drive out of a covered area, why not simply switching the radio module off!? I don't get the point here :?: :!: :?: :!:

[Jason Dunn]

2nd: Changing it doesn't makes sense. For example if you would change it to let's say 10 minutes and you would drive though a tunnel where you lose the GSM connection, you would be offline for the next 10 minutes because your mobile phone doesn't scan for network coverage the next x minutes...

Arne, it might not make sense to you, living in GSM covered country, but as I explained in private already, this is going to be a significant issue to those of us who live in larger countries that are NOT covered 100% by a GSM signal. This is not a problem for you, but it is a problem for others in Canada and North America.

If you drive out of a covered area, why not simply switching the radio module off!? I don't get the point here

Simple: because you have to remember to turn it back on. If you forget, you're 100% off-line until you remember.

[sweetpete]

Arne, it might not make sense to you, living in GSM covered country, but as I explained in private already, this is going to be a significant issue to those of us who live in larger countries that are NOT covered 100% by a GSM signal. This is not a problem for you, but it is a problem for others in Canada and North America.

If you drive out of a covered area, why not simply switching the radio module off!? I don't get the point here

Simple: because you have to remember to turn it back on. If you forget, you're 100% off-line until you remember.

Jason, I understand your frustration having been using Fido for almost 5 yrs here in Canada, but what Arne says is really the easiest and best approach. When I drive to Whistler from Vancouver, I know that I will be out of Fido coverage for about 1 hr of the drive and I have simply gotten in the habit of turning off my phone or leaving it plugged in the car charger (which should come out for the XDA and other converged devices soon!!).
I would think that people would be worse off changing the search retry setting one day and forgetting to turn it back down. Then, when you're driving in and out of parkades or bad coverage areas, you might be without signal for 10 minutes. That would be more frustrating. This has never been a user setting in GSM phones nor it should be.

[Jason Dunn]

I would think that people would be worse off changing the search retry setting one day and forgetting to turn it back down. Then, when you're driving in and out of parkades or bad coverage areas, you might be without signal for 10 minutes. That would be more frustrating. This has never been a user setting in GSM phones nor it should be.

That's where we disagree: you think it would be horrible to be without signal, I think it wouldn't be a big deal and I'd rather have the battery savings when I'm out of the city. I'm simply suggesting that giving the user a choice would be helpful. I am not suggesting that you be forced to change it on your own device. You and Arne are arguing that I should not be given a choice. 8O

I don't understand why GSM users are so defensive about this - why is asking for a choice such a bad thing? :? We're dealing with a new class of device here, and it's naïve to think that the rules that worked for phones will be 100% perfect for WDA devices.

[Arne Hess]

Arne, it might not make sense to you, living in GSM covered country, but as I explained in private already, this is going to be a significant issue to those of us who live in larger countries that are NOT covered 100% by a GSM signal. This is not a problem for you, but it is a problem for others in Canada and North America.
Even if I still don't see the point - also not for Canada, I've replied to "Venturello" (not to you cause you already explained it for me in detail and I "understand" what you mean) and "Venturello" comes from Spain where I think is a pretty good coverage:
http://www.gsmworld.com/imap/gsminfo/maps/es/te/images/0_0_0.gif
So I don't see the point for him.
Simple: because you have to remember to turn it back on. If you forget, you're 100% off-line until you remember.
If I forgot to cut the time in high density covered areas, I'm out of service too because I configured the poll for a to long time frame (e.g. tunnels).

[sweetpete]

I don't understand why GSM users are so defensive about this - why is asking for a choice such a bad thing? :? We're dealing with a new class of device here, and it's naïve to think that the rules that worked for phones will be 100% perfect for WDA devices.

:D I don't think it's a GSM user issue. There are times when users shouldn't have the choice. You and I and most the people in this forum are savvy users :wink: , but having been a support rep and in retail sales selling many of these types of devices (phones and PDA's for 3 yrs), I can tell you that it's a BAAAADD thing :evil:

I guess knowing what coverage is like in Alberta, I don't see where you'll be expecting coverage to return anytime soon. Once you leave the footprint, it ain't coming back for a while :cry:
http://www.fido.ca//portal/en/info/Discover/images/imgCarto-PopCanada.jpg

I don't think giving someone like you the choice is a bad thing since you're capable, but this stuff is in the standard and stack and to change it would be a pretty large undertaking. Like you said, since we are in a new class of products, things like this need to be considered and that is very valid :!:

[marlof]

If you drive out of a covered area, why not simply switching the radio module off!? I don't get the point here

I think it's simple: two settings: one polls every 15s, and is great for good covered areas with tunnels and stuff. The other polls only every 10mins. In stead of switching off the radio, you switch it to another position. Just like you have to remember to switch the radio back on to see if you get coverage in your new location, you will have to remember to switch the radio to the 15s polling when you regain coverage.

Or..... may be there could be a setting that would poll 100 times for 15s, and after 100 times ( you should have been out of smaller tunnels by then ! ) automatically fall back to 10 mins. As soon as the unit regains coverage, it could go back to pinging every 15s. I think this wouldn't harm a soul, and could be pretty helpful to some.

[Arne Hess]

Arne, it might not make sense to you, living in GSM covered country, but as I explained in private already, this is going to be a significant issue to those of us who live in larger countries that are NOT covered 100% by a GSM signal. This is not a problem for you, but it is a problem for others in Canada and North America.
Just an additional technical explanation why longer polls doesn't makes any sense: GSM works with HLRs (Home Location Registers) and VLRs (Visitor Location Registers) and the device need to send its location back to the network. If it don't do it, you will not reachable anymore, even if it looks on the display that you are logged in to the network because the network try to reach you through the wrong MSC (Mobile Switching Center) where you aren't attached to any longer. Clear!? ;-)

BTW: This network architecture looks different for 3G but in general it's the same, so also with 3G will not find any major differences!

[Arne Hess]

I don't see your point here too! Doesn't matter which device we are talking about, we are talking about wireless implementations so I don't care if it is a Cell Phone, Smart Phone or Wireless PDA. It's about providing connectivity and this is something, GSM works with since 1987!
So what's the point with "We're dealing with a new class of device here"? We have Smart Devices for a long time here, started with the Nokia 9000! And there it worked... You see...? :-(

[marlof]

Just an additional technical explanation why longer polls doesn't makes any sense: GSM works with HLRs (Home Location Registers) and VLRs (Visitor Location Registers) and the device need to send its location back to the network. If it don't do it, you will not reachable anymore, even if it looks on the display that you are logged in to the network because the network try to reach you through the wrong MSC (Mobile Switching Center) where you aren't attached to any longer. Clear!? ;-)

Correct me if I'm wrong, but if you switch back to polling frequency, you want to do that because you're already not attached to the network. Your advice to switch off the radio completely would have you out of reach completely, until you switch the phone back on. But if there's a solution where the polling frequency when you're already outside the covered area could be switched down, it would at least automatically try every 10mins or so if it could find coverage. I assume that would put you sooner in reach that just leaving the radio off. Or am I overlooking something? ( I'm learning here, so bear with me.... )

[Jason Dunn]

So what's the point with "We're dealing with a new class of device here"? We have Smart Devices for a long time here, started with the Nokia 9000! And there it worked... You see...? :-(

It's simple Arne: battery life is far more of a concern on a PDA than on a cell phone with a removable battery.

[Arne Hess]

I guess knowing what coverage is like in Alberta, I don't see where you'll be expecting coverage to return anytime soon. Once you leave the footprint, it ain't coming back for a while :cry:
Hey, the Alberta coverage doesn't looks so bad to me:

http://www.gsmworld.com/imap/gsminfo/maps/ca/rw/images/0_0_0.gif
http://www.gsmworld.com/imap/gsminfo/maps/ca/rw/images/1_0_1.gif

[Jason Dunn]

Hey, the Alberta coverage doesn't looks so bad to me

It's not - it's quite good. In the city, I always have signal (so far). It's just that in the particular case I was talking about, I was 1.5 hours outside the city and the GSM coverage zone. Please trust me when I say that I didn't have coverage.

[Arne Hess]

No no, I believe you for sure. I only wonder if you should think about trying another network too?
I mean, we had the same situation here in Germany and while one network doesn't covered the one area while another did a great job.
It's always frustrating to see in the network search, that in general GSM is available but you have the wrong SIM card... :cry: :cry: :cry:
BTW: I don't have a clue how far away a 1.5 hours drive is from the city in Canada. I think it's far but is it between nowhere and nowhere as it sounds?

[sweetpete]

No no, I believe you for sure. I only wonder if you should think about trying another network too?
I mean, we had the same situation here in Germany and while one network doesn't covered the one area while another did a great job.
It's always frustrating to see in the network search, that in general GSM is available but you have the wrong SIM card... :cry: :cry: :cry:
BTW: I don't have a clue how far away a 1.5 hours drive is from the city in Canada. I think it's far but is it between nowhere and nowhere as it sounds?

You're right Arne, there is a better coverage provider with Rogers, but they don't have the best echo cancellers and call quality compared to Fido/Microcell.

http://www.shoprogers.com/images/coverage_gsm_alb.gif

I believe the best solution mentioned is to have an algorithm that increases the search parameter as the amount of time increases outside of coverage. As soon as the phone regains signal, and/or is shut off and on, this is reset back to 15 secs. But, as you can see from the map in my previous post above, this would only be useful for Microcell because they concentrate stricly on urban coverage. Rogers doesn't have this same problem as can be seen in this map.

[Ed Hansberry]

No no, I believe you for sure. I only wonder if you should think about trying another network too?
HAH! Arne - in North America, a new network generally means a new phone with a different technology - TDMA, CDMA, etc. It is so pathetic over here. :bad-words:

[Marc Zimmermann]

I only wonder if you should think about trying another network too? I mean, we had the same situation here in Germany and while one network doesn't covered the one area while another did a great job.
Yup, that should be checked before making a judgement about GSM as a whole.

[Arne Hess]

No no, I believe you for sure. I only wonder if you should think about trying another network too?
HAH! Arne - in North America, a new network generally means a new phone with a different technology - TDMA, CDMA, etc. It is so pathetic over here. :bad-words:
Generally new? It seems that in the Albetra area are two GSM networks available...
Beside this you are right... To many wireless technologies in the US... :(

[Jason Dunn]

I think it's far but is it between nowhere and nowhere as it sounds?

Yes, I was in the middle of nowhere. :lol: I truly wasn't expecting the GSM coverage anyway, so that's not the issue at all. :D

[Venturello]

Nice discussion everyone. Just a quick question, where do u get the coverage maps from? Something else, it is a hobby of mine to drive on weekends (got a car for that even), so I have traveled all over the region. The map of Spain, at least in the detail I can see, is not accurate. There are LARGE regions of Catalonia (the eastern tip of spain) and the pyrinees (all the border with France) where there is no coverage - even regions with small towns and villages. Not small zones as in mountain roads or tunnels (duh, I know this far) but whole zones where, if there was an antenna, there should be signal (open, no obstructions). About the polling in this type of networks, I understand the concept of why it is needed.

I also do 'senderism', trekking I think it is called in the US, and when I do buy a pocket pc phone edition (which I will certainly do), I would need to turn off the phone section to save power. This are trips by foot to remote places where in many of them there is no coverage, and many times they are several days long.