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Call quality & signal issues - diagnose & fix when T-Mobile can not.

celticflame

The figures below relate to my experiences described in the thread Better call quality using Solavei SIM on T-Mobile network

-- http://support.t-mobile.com/thread/38418?start=0&tstart=0

 

Mid month, I got a new SIM from the T-Mobile store.  On the subjective side ... it feels better.  Faster connection, better call quality, stronger signal.  The first 2 below readings are from the week after porting -4189 to Solavei.  The last was made from the same location/same settings from around 10PM to 10AM.


Open Signal Maps shows:

                                        Day 1    handsets 24 inched apart                              Day12-same spot

                                    T-M -4190                                      Solavei -4189                   new SIM-4190

Avg signal                    9% /-104 dBm/ 4Asu                 37%/ -99/ 7                   32%/-99/7

time without signal        33%                                               6%                                      4%

time on network       2G 11%, 3G 58%, ? 31%         2G 26%, 3G 74%     2G 5%,3G 91%, ? 4%

-----

I've been a T-Mobile customer over 10 years.  Generally happy with the service but I don't remember T-Mobile ever helping or really addressing an individual signal or call quality problem beyond re-boot ... reset ...  They were not any better in the above current attempt.  Before making the above change, we were planning to leave T-Mobile, and did move to Solavei.  Our service is now far better.  Probably could have been this much better for the past 18 months.

 

I would like to learn from the experiences of others and really explore how to trouble shoot a problem, find what tools are available, what a good signal looks like and how to make real improvements customers like me want to stay with T-Mobile and get the service we are paying for..

 

Please join in.

  • 1. Re: Call quality & signal issues - diagnose & fix when T-Mobile can not.

    Great effort at trying to imporve your service. I will add a few of my observations, having been a T-Mobile customer for the last 4.5 years.

     

    -104 to -114 dBm signal strength (0-1 bars) is generally not 99% reliable inside a building for holding calls, but is fine for 3G/4G data use inside, or any use outside. I'm sure you already know this.

     

    With weak signals on higher frequencies (1700/2100, 1900), the phone choice can make a signigicant difference in performance. My experience is that Motorola and Nokia are the best, while Samsung and LG are the worst, for RF reception. I'm not sure if this has to do with experience/patents, SAR levels, or just lack of effort on the Korean manufacturers' part. As an example, my Motorola Defy will get 10 dBm better signal than my wife's new LG L9 in the same location inside a building for 1700/2100 reception. This makes all the difference in receiving calls and holding calls. It also helps with data throughput rates. I have no experience with HTC, Sony, or the China based phone manufactuers.

     

    So with weak T-Mobile signals inside buildings for many users in the "good" to "moderate" map area,  the answer is either a repeater or wi-fi calling to reach the 99% levels. We went the Wi-Fi calling route and have generally been happy with it. Ocassional outages by either T-Mobile Wi-Fi calling servers or our broadband provider have not reduced our overall experience, because the tower network (near windows inside or outside) becomes the backup. Some might argue that you're paying to support T-Mobile's network with such a setup. To that I say: 1. We have Wi-Fi regardless of mobile phone service. 2. No way can mobile data from any carrier match speed/pings, reliability/signal strength, and unlimited data (200+ GB use) of our broadband Wi-Fi connection. 3. T-Mobile does have inexpensive ($5) low use data plans if you are on Wi-Fi a lot.

     

    We've only had one tower based outage during this time period and it was last Fall. No 3G reception inside or outside on two different 3G phones. Called 611 to report tower outage. Agent created a trouble ticket. 3G signal came back on about 6 hours later. My guess is that the towers were being worked on for the refarm of 3G to 1900.

     

    Speaking of refarm, anyone thinking about using T-Mobile should get a phone compatible with all T-Mobile frequencies (in their market) for the best experience. My experience improved switching from a 2G only phone to a mostly 3G (selectable) phone since November.  Also, I have roamed on UMTS/HSPA 850 MHz (AT&T) in locations where 850/1900 2G/GSM roaming didn't work. Maybe this is a result of the failed takeover 3G roaminng agreement? Granted, I had the Defy locked to 3G in such locations, so it couldn't switch to 2G.

     

    It seems your new SIM card, or maybe coincidental tower upgrades, fixed some of your issues?

     

    The very low cost of our plan ($95/mo. Value Plan for 4 lines), combined with the plan features and post paid "frills," makes T-Mobile the best choice for us. For voice/text coverage in some not covered remote locations, forwarding calls to an Airvoice SIM/line or a PagePlus phone is a nice low-cost backup.

     

    When T-Mobile LTE/Sprint LTE starts competing with AT&T and Verizon, then falling LTE data costs will take care of data holes. This is coming by the end or this year or early next year. Virgin Mobile already has 500 MB 4G Mi-Fi for $5/day. They just have to add LTE to the $85 devices.

  • 2. Re: Call quality & signal issues - diagnose & fix when T-Mobile can not.
    celticflame

    Great info.  Thanks!

     

    The only handsets I tested side by side were HTC G2, My Touch, My Touch Slide and Sensation vs Blackberry.  Blackberry consistently maintained a connection to both WiFi and cellular where the HTC handsets could not.

  • 3. Re: Call quality & signal issues - diagnose & fix when T-Mobile can not.
    celticflame

    The following is an exchange I had with T-M support on SIM cards.---

     

    Tell me all about SIMs.  They apparently do more than network

    authentication.  What SIM options are available?  Why can't we test my

    handsets call quality using each SIM?

     

    The current SIM cards that we offer are GBA and are backwards compatible with all of the technologies we use. The only difference in the GBA SIM cards from our Legacy and UICC SIM cards is the amount of storage space the GBA offers.

     

    How is my T-Mobile SIM different from a Solavei SIM?  Why did changing my SIM in 11-2011 allow me to connect to a tower the same handset did not connect to before the change?  Are some SIMs defective or go bad with use?

     

    Correct, the GBA SIM card is the only type of SIM card that we offer. I apologize but i cannot speak to the specifics of the Solavie SIM cards but yes, our legacy SIM cards did suffer from SIM exhaustion. SIM exhaustion occurs after approximately 90,000 attempts to connect to the network. The UICC SIM cards did not suffer from this and our new GBA SIM cards do not suffer from SIM exhaustion when connecting to the 3G/4G network but have a limited amount of attempts at connecting to the 2G network. The number is much higher than the legacy SIM cards at 360,000 attempts.

     

    On the gold side of your SIM card you will see the letters TM and some numbers. Do you see a TM90xx or a TM91xx or TM92xx?

     

    TM90 is UICC

    TM91 is GBA

    TM92 is GBA

     

    If you do not have any numbers or letters next to the TM you are actually using a Legacy SIM card.

    ---

    I tried 3 new SIMs in each handset since going Andriod.  Each change showed improvement.  I previously thought SIM cards were primarily for network authentication.  Aparently they do far more and, I am a slow learner. 

     

    I "upgraded" 3 BB handsets to Android in 01/2011 .  We had severe problems from the start.  We tried new SIM cards in all.  This helped with WiFi connections and WiFi calling but we did not notice improvement in cellular.  In August 2011 we tried different new Android handsets using the same SIMs.  They were better and far more consistent but still had signal problems support was unable to fix.  In November, I installed the Open Signal Maps app.  I discovered my handset bounced between 3 towers but never connected to the closest T-Mobile tower.  Support couldn't explain this and offered no suggestions.  On the same call, they activated the new SIM cards that came with the new handset.  My next Open Signal Maps reading showed a stable connection to the close tower the replaced SIM wouldn't connect to.  I detailed this in a thread at the time but it has since been suppressed.  I activated new SIM for the other handsets and got the same improvement.  At this point I stopped pursuing signal issues with support.

     

    Cut to December 2012 and I am looking forward to the new year and my T-Mobile indenture coming to an end.  My service was simply not good enough to justify staying at T-Mobile, even at a lower cost.  I decided to do some testing before making a move.  See the below links ...

    Better call quality using Solavei SIM on T-Mobile network

    http://support.t-mobile.com/thread/38418

    Motricity exec to launch MVNO Solavei on T-Mobile's network

    http://support.t-mobile.com/message/214051#214051

     

    Had T-Mobile enabled me to enjoy my current call quality for the past 14 months, I would be on a new contract with new handsets.  Why did T-Mobile allow me this second rate service for so long when achieving this improvement was so simple?  They don't seem to have any procedure in place to test or ensure their customers are getting the best quality available.  Even while they are loosing customers, the current customer is hammering support and has an example of improvement they could follow.  Jessica did suggest new  SIM cards in her first response but I thought I was already using a new SIM.  Even after detailing my problem, I had to ask to discover my SIM was 2 generations old at 15 months.  So it is up to each customer to diagnose and discover what it takes to get the best T-Mobile has to offer.  Open Signal Maps is a great app to start with.

     

    http://opensignal.com/

     

    May the Force be with you!

  • 4. Re: Call quality & signal issues - diagnose & fix when T-Mobile can not.

    So it seems, from your experience, that HTC is not so good for radio frequency reception and old school Blackberry is good? This wouldn't surprise me at all.

     

    I had no UMA connection problems with my Samsung T339, although the cellular antenna in this flip phone is mediocare at best. T-Mobile is reducing 2G/GSM spectrum with the refarm to 1900 UMTS/HSPA, so basically crowding remaining users on a smaller slice. Less GSM spectrum means less available channels in some high use locations and this can mean dropped calls when moving from cell to cell. This was my main reason for switching to my wife's old Defy.

     

    I've encountered some wi-fi calling issues with the Defy that were not there on UMA. For example, Wi-Fi calling will not start (stuck on enabling) some mornings when I turn on the phone, until it connects with a tower first. This moring I had to walk outside and also turn network choice to automatic from 3G only because 3G only wasn't registering on the towers. So then it registered on 2G and quickly switched to 3G and then when I came inside it evabled wi-fi calling. I have also gotten the "W009.2 Unable to connect. Failed Location Update." error, which may be related, and/or associated with E911. I will see if CS can give me a straight answer to the 9.2 error in the Defy forum. So there are definitly issues associated with the Kineto W-Fi calling app. that weren't fully thought out by T-Mobile and I trying to work around those right now.

     

    The latest IMS version of Wi-Fi calling seems to be more reliable than the Kineto app. for Android. My wife's LG L9 is extremely stable on our home Wi-Fi network for wi-fi calls. Call quality is good to.

  • 5. Re: Call quality & signal issues - diagnose & fix when T-Mobile can not.

    Great info. about SIM cards and connecting to towers. Most people assume that closest tower and strongest signal is standard operator procedure and not related to type of SIM card. You're evidence contrdicts this for your location. Other vairables that might come into play include network congestion in your home location (pre-paid and T-Mobile MVNO users included) and legacy networks that were acquired (versus T-Mobile installed towers) which results in tower hopping because of roaming agreements. It sems really hard to say unless one could talk directly to a local/regional network engineer.

     

    What is your experience locking the network setting to 3G/4G only?

  • 6. Re: Call quality & signal issues - diagnose & fix when T-Mobile can not.
    celticflame

    This may be of interest to us techies ... but not most users.  My wife has always left cellular, phone and Internet decisions to me.  This year she said "no more T-Mobile!"  I knew we experienced a very bad 2 years but hadn't realized how frustrated she was with her cellular.  She just want's a phone that works when she needs it without altering settings as she changes locations.  She is OK with Solavei, or, I suspect the T-Mobile service I now enjoy. 

     

    Neither of us is considering an iPhone.  Perhaps T-Mobile could benefit from making a better effort to give long term customers the full benefit of what their current network has to offer.  I know I spent more time with support between 01/2011 and 01/2012 than in all the previous 10 years and ended up here.  How does this benefit either of us?

    umauser wrote:

     

    ... T-Mobile is reducing 2G/GSM spectrum with the refarm to 1900 UMTS/HSPA, so basically crowding remaining users on a smaller slice. Less GSM spectrum means less available channels in some high use locations and this can mean dropped calls when moving from cell to cell. This was my main reason for switching to my wife's old Defy.

     

    I've encountered some wi-fi calling issues with the Defy that were not there on UMA. For example, Wi-Fi calling will not start (stuck on enabling) some mornings when I turn on the phone, until it connects with a tower first. This moring I had to walk outside and also turn network choice to automatic from 3G only because 3G only wasn't registering on the towers. So then it registered on 2G and quickly switched to 3G and then when I came inside it evabled wi-fi calling. I have also gotten the "W009.2 Unable to connect. Failed Location Update." error, which may be related, and/or associated with E911. I will see if CS can give me a straight answer to the 9.2 error in the Defy forum. So there are definitly issues associated with the Kineto W-Fi calling app. that weren't fully thought out by T-Mobile and I trying to work around those right now.

     

    The latest IMS version of Wi-Fi calling seems to be more reliable than the Kineto app. for Android. My wife's LG L9 is extremely stable on our home Wi-Fi network for wi-fi calls. Call quality is good to.

  • 7. Re: Call quality & signal issues - diagnose & fix when T-Mobile can not.
    jon_doh

    I'll be the first to admit I've had my share of problems with T-Mobile and their fake coverage maps and rude customer service.  But I also have to post that I was experiencing dropped calls and reception issues at my house and filed a ticket with them.  I was getting around 107 dbs from a tower a half mile from my house.  It took two tickets, but what I was told was that the technician tilted or repositioned the signal - not sure of the exact technology - due to a terrain issue.  After the adjustment I now get between 92 -97 dbs, which is enough to hold a conversation with very few drops.  My download is between 6 and 7.7 MPS, which I'm happy with.  Although, I have gotten as much as 18 MPS in an area with a better signal (73 dbs).

     

    So, my advice to you is to open up a ticket and keep filing them until they respond.  Maybe I got lucky, but I was pleased that they sent out a technician to the tower and an adjustment was made.

  • 8. Re: Call quality & signal issues - diagnose & fix when T-Mobile can not.
    celticflame

    That's great!  Glad to hear success stories.  Are you taking new clients? 

     

    Could you explain your signal readings, how you measured and what a good or bad signal reading or goal is.  It appears my signal readings above are at best borderline even as T-Mobile coverage maps show me on the line between dark and medium green.  I've had a ticket opened over 45 days now without any action taken or improvement. 

  • 9. Re: Call quality & signal issues - diagnose & fix when T-Mobile can not.
    jon_doh

    Your signal is not in the range sufficient to support voice calls.  Your dbs should be 80 or below.  The lower, the better.  After 80 you're in drop call territory. T-Mobile actually has a tower a lot closer to me than AT&T, yet AT&T delivers a signal down in the 60's, which is outstanding.  The best I've gotten on T-Mobile is 73 dbs as I previously reported. The problem with T-Mobile's crappy network is 95% of the time when I travel I'm getting a signal in the 90's, often even over 100 and having calls go straight to voice mail or being dropped.  I'm also on Edge most of the time and can't get emails.  But even on their 4G network the signal is poor.  They definitely a network issue, but instead of improving their network they waste money running ads dissing AT&T and blow billions moving the cheese from 1700 to 1900 MHZ so they can try and woo AT&T's old iPhone customer base. 

  • 10. Re: Call quality & signal issues - diagnose & fix when T-Mobile can not.
    celticflame

    But, according to T-Mobile coverage maps, I'm right on the line between Excellent & Very Strong signal.  And now is right after T-Mobile engineers spent 45 days eliminating any possible problems at my address.  Inside signal = -103 and outside -93 but I'm getting 2 to 4 bars at these levels.  Are your sure your numbers are valid in Maryland? 

     

    Great information.  What you say matches my experience while not what the bars show.  Many thanks.  For both versions. 

     

    http://www.tested.com/tech/android/557-how-to-measure-cell-signal-strength-on-android-phones/

     

    -100 dbm or less = Unacceptable coverage

    -99 dbm to –90 dbm = Weak Coverage

    -89 dbm to – 70 dbm = Medium to High Coverage

    -69 dbm or greater = Strong Coverage

     

    https://opengear.zendesk.com/entries/22462692-Measuring-cellular-signal-strength

     

    http://powerfulsignal.com/cell-signal-strength.aspx

     

    Perhaps I'll take another shot at T-Mobile's engineers now that I know they are capable of answering.

     

    Signal database --  http://opensignal.com/

    jon_doh wrote:

     

    Your signal is not in the range sufficient to support voice calls.  Your dbs should be 80 or below.  The lower, the better.  After 80 you're in drop call territory. T-Mobile actually has a tower a lot closer to me than AT&T, yet AT&T delivers a signal down in the 60's, which is outstanding.  The best I've gotten on T-Mobile is 73 dbs as I previously reported. The problem with T-Mobile's crappy network is 95% of the time when I travel I'm getting a signal in the 90's, often even over 100 and having calls go straight to voice mail or being dropped.  I'm also on Edge most of the time and can't get emails.  But even on their 4G network the signal is poor.  They definitely a network issue, but instead of improving their network they waste money running ads dissing AT&T and blow billions moving the cheese from 1700 to 1900 MHZ so they can try and woo AT&T's old iPhone customer base. 

  • 11. Re: Call quality & signal issues - diagnose & fix when T-Mobile can not.

    Your numbers are not correct. I've been using T-Mobile for 4.5 years and only 5-10 dropped calls on their network the whole time. Lately I've had some dropped calls on Wi-Fi calling, but that's another story and involves an ISP also.  Even inside many commercial buildings T-Mobile works fine, because they locate towers near such areas due to traffic patterns. Obviously there are old brick and concrete buildings where T-Mobile's signals won't penetrate and only lower freq. spectrum will work. Here are my signal numbers for inside and outside my standard frame home using a Moto Defy:

     

    3G (1700/2100 MHz)- Inside Average -100 dBm. Outside Ave. -95 dBm.

     

    2G (1900 MHz)- Inside Ave. -105 dBm, Outside Ave.  -95 dBm.

     

    2G or 3G (850 MHz or 1900 Mhz)- Emergency Calls Only, -111 dBm, Inside Ave. via AT&T (MNC 310-410).

     

    The number of bars shown on a phone varies from model to model. My Moto Defy will show 4 bars at -91 dBm and 5 bars at -69 dBm near a tower.  Big range there. Some Samsung models have a 6 bar scale and more evenly space out the readings.

     

    Can a user do things to minimize dropped or missed calls with T-Mobile? Absolutely. Keep the phone in a holster and not in your pocket/backpack/purse. Hold the phone with your fingertips instead of wrapping your palm around it. Yes, this simple act can mean the difference between a stable -101 dBm call and a -109 dBm call dropping. Also, look at the diagram of the phone in the manual to figure out where the cellular antenna(s) are and try not to cover them up with your palm if possible. Use of corded or cordless headsets also greatly reduces signal interference.

     

    In an ideal world all the major carriers would have a mix of low and high band spectrum and competition would be intense to keep customers. The FCC mucked it all up with spectrum  auctions/allocation favoring the teleco incumbents and so T-Mobile and Sprint and other carriers have to deal wtih the limitations of higher frequency spectrum. Not all customers want to mess with such details and just want the easy route, regardless of cost. Others are willing to compromise to save a buck or two.

  • 12. Re: Call quality & signal issues - diagnose & fix when T-Mobile can not.
    jon_doh

    @umauser, I meant to type after "90" you're in drop call territory.  80 was a typo.  But don't be such a fan boy, look it up on the internets.

  • 13. Re: Call quality & signal issues - diagnose & fix when T-Mobile can not.

    @jon_doh

     

    No need to look up anything up on the "internets." I went for a walk yesterday in my neighborhood. During that walk I had a landline quality 15 minute conservation on T's 3G using an average signal strength of -95 and the call didn't drop. I made another call from our upstairs bedroom for 15 minutes with a friend (-99 to -103 signal strength) and the call quality was good and it didn't drop. See where I'm going with this logic?

     

    As far as being a fanboy of T-Mobile, when Verizon offers a 4 line BYOD family plan with unlimited talk (due to free options) and unlimited text and 4 smart phone data plans (3 200 MB and one fully unlimited) for $95/mo, then maybe I'll change teams.

  • 14. Re: Call quality & signal issues - diagnose & fix when T-Mobile can not.
    celticflame

    I took a walk yesterday carrying my handset and my old HTC G2.  I walked to the closest T-Mobile "tower" which turned out to be high on 2 phone polls facing opposite directions.  I never got a signal better than -87.  As I got within about 250 feet, my signal jumped to another tower and never re-connected to this tower again on my walk.  Both my HTC G2 anf MyTouch4G get the same reading.  I charged my old Blackberry(always worked well) to see if the signal read same or close.  Charged fine but connected to AT&T network.  I don't have a SIM in the handset.  I tried setting network to manual but it still couldn't find T-Mobile and wouldn't show a signal reading.  The G2 has a T-Mobile SIM no longer activated. 

     

    I took signal readings from many locations Friday and Saturday.  It generally read between -85 and -99.  I got 4 readings below -80 -, 67/23, -71/24, -73/20, -75/20 and several over -100.  T-Mobile's coverage maps show my mother's house in excellent signal area.  I get -89 outside and -96 inside.

     

    I will try to test other handsets in the same locations as my HTC's.  If my HTC handsets are showing accurate readings, T-Mobile's excellent to very strong signal is generally between -85 and -98.

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