Reply With QuoteSounds rubbish to me - I thought the SIM only 'authenticates' you against the provider. You'd think that would be a binary response.
I rang Vodafone customer service today to complain that their coverage is now much worse than five years ago and that I had been paying too much per month for too little, and that I was going to try O2.
Customer services asked me how long since I changed the SIM. Three of four years ago I replied. "Ahh, that might be it, you get better reception with a new SIM card."
As an engineer, previously in electronic engineering and telecoms this one floored me and I can't for the life of me think of why this might be the case, but what do you think? Any experience of this anyone?
Sounds rubbish to me - I thought the SIM only 'authenticates' you against the provider. You'd think that would be a binary response.
I am with Vodafone so will ask the same question.
A damaged or out of date SIM card can give symptoms that look like poor reception. I'd be surprised if that was true of a 3 year old one but I have seen it on an older one of that helps.
Agreed, my first thoughts to. Perhaps though it also contains some details of capability? Maybe with 4G there are now some enhancements not included in the "capability" of the old SIM card, even though the phone (S3) might be capable of them?Originally Posted by racingclub
Anyway the Vodafone shop gave me a blank SIM that I can switch over to at my leisure (once I've copied the contacts over) by visiting one of their web pages. Happy to do that, but CBA'd if the idea is rubbish.
My experience with Vodafone is that when I passed to 4G less than 3 years ago, I had to change my SIM to get 4G. I also changed it 3 months ago because I bought a new phone with nano SIM.
Changing SIM is pretty easy, walk into any Vodafone shop, they will give you one for free and do it for you. Alternatively you can do it yourself on their website, it takes less than 5 min. Of course if you have your contacts on the SIM, its a problem, but in 2016 not sure how many people still store contacts on a SIM.
My SIM is 12 y.o., has had a shocking life and I have recently cut it to size myself. Not the least reduction in coverage.
Oh and I store contacts on BOTH phone and Sim.
I wont go into the tech data on it as its boring, but yes it can.
when you insert a new sim, you are in essence deleting your old sim from the 'system' this in turn forces your carriers network to force an update to the network, making cell towers 'aware' of the new sim, this can improve reception as any new agreements between carriers and their cell towers and any new cell towers since your last sim will be 'aware' of the new sim, allowing it to access them.
in turn 'improving' your reception, in areas you previously had bad reception, this is why they ask.
That makes sense and worth knowing.
Thanks
Are you saying that if my carrier adds a new tower to their cell network, that it won't pick up my phone unless I change the SIM?
That's good to know. Thanks.
Based on that, if you remove your current SIM, insert another (old/unused) SIM, restart phone, then replace back your original SIM - would it force a reset of your original SIM? (I hope that makes sense....)
Sounds daft to me.
It also does not explain LOSS of reception.
Leaving Vodafone is the best thing you can do they are terrible.
I would agree.
I'm stuck with them as I've a work's phone, but their signal quality is pretty poor in many places.
M.
in principle yes, but no where near all the time. Over time and as the sim card gets older, more and more towers are missed, but again this doesn't mean it is de facto, as other users might be lucky and never have a problem, depending on area/network provider/agreements between network providers etc.,
there is a chance the tower will ignore your sim, and another older tower will make the connection, a lot of this has to do with the crossover between 2G/3G and 4G, and the protocols used to 'handshake' between your sim and the cell tower.
it is more common on low power/widespread cell towers, London is a good example, as opposed to high power single towers out in the sticks.
it does explain loss of reception perfectly, if you are not being picked up by your nearest cell tower, you might not get reception or low reception, if you are moving between cell towers, you may move from one with a good reception to one that doesnt pick you up, causing loss of reception.
what I will say is I studied sound engineering and know a few things about telecoms, but in no way am I an expert, and like another poster here who works in Telecoms, you can work in the industry and know nothing about 90% of it, being good at the 10% you know.
the following information was gained during one of my many conversation with my cousin via skype one evening, he lives in Oz and is a big deal in new tech roll outs in mobile comms.
he was at the forefront of of 4G (LTE) and spent a lot of time in Sweden and Norway during this development, and during one of the conversations he told me about this, and the inability of the tech to 'refresh' cell towers to older sim's, this was a couple of years ago, and I know they have been working on it, but as to date it is still an issue.
if anyone is interested in the full tech breakdown on this, I am sure he could send me a couple of lengthy PDF's explaining it, which I would happily share, if he was OK with it.
Last edited by soundood; 6th October 2016 at 21:38.
Yes, I'd be interested in that. Sounds like nonsense, so please educate me.
BTW, what's sound engineering got to do with telecoms?
if you read the post properly you would see I didnt say anything about a link between sound engineering and telecoms, here is the quote,
as you can see 'and' is added in there, and no I wont be doing anything for you as your attitude stinks, go google itwhat I will say is I studied sound engineering and know a few things about telecoms
as a start point go google 'Cancel Location' command cell towers, which covers triangulation etc. and signal strength between towers.
there is a lot to read there, but down that path you will come across the more technical reason that I have tried to explain above.
and to be fair, this is only one facet of the issue, as there are other reasons as to why it can happen.
Last edited by soundood; 6th October 2016 at 23:23.
Thanks. I used to know this stuff fairly well. I'm a bit rusty now but no need for more detail on my account. I didn't realise that the protocols didn't work as intended though.
'dood: I'd be interested in any further information you can provide, thanks. When I put the new SIM card in I'll update the thread with the result.
OK - explain this.
Exact Same location (to within half an inch), same cell tower (there is only one in range). Day one (fine and sunny) 2 bars. Day 2 (overcast) no signal.
Any big trees nearby?
We had some old 2g Sims out there that were providing gradually worse service and reception. When we swapped those for 3g/4g it was much improved.
Clouds are made of water. Water is electrically conductive. Electrically conductive materials attenuate EM radiation. Basic high school physics.
Ok.
Thanks for the effort to put the issue in understandable language.
I understand that I cannot understand that.
I accept that it will be a good thing then, that I will be changing my 10 y.o. SIM for a new one coming week or so.
Makes me happier with the step to a smartphone which I do not entirely appreciate at all. Already had the first agro about it with the charming company who gave me the thing for my birthday this Monday... 'What's all those whatsapp messages you get from women???'
There is no good answer.
I will have it turned off wifi OFTEN!
My old brick was a nice silent partner.
yes this and reflection quality, signal will either reflect of absorb in different weather conditions, into clouds or no clouds, this coupled with the EM radiation all around us can have an affect, but a separate issue from the one above, or a combination of both.
I spend many hours a day talking/recommending antenna to people... believe me it's a mine field trying to understand signal propagation. Just accept that sometimes it'll work and sometimes it won't :-) You can try to shift it more towards the 'it'll work' by applying some basic sensible theories but then there are still no guarantees!
Fresnel Zones ?
indeed, one of my specialties within sound engineering was programming radio mic's, this was when they ran on the old channel 69, I done a lot of work around London, and a job I hated was at Wimbledon Theatre, while Wimbledon Tennis was on,
I would spend days working out Frequency's that could be used without inter modulation problems, using sum and difference calculations to find the sweet spots, then they would add one mic into the mix and it was back to the drawing board.
this coupled with antenna amplitude, was a nightmare, as you would push the signal to cover, then so would others, including Taxi drivers, and all of a sudden you had cross talk from a local firm over your mic's during a show.
I'm with o2 and have had some problems with reception lately, I keep getting txt from them apologising for connection faults, I rang them and was given the same response "change your sim" as it was 4 years old, after reading this thread I'm going to pop in the local o2 shop and get it change today will update when done.
No need to change the SIM. Simply turn "flight mode" on and off. This will register your phone to the nearest tower thus improving the reception. This works for me for years, my SIM is some 15 years old and works perfectly in SONIM XP 3000. For iPhone I have new one nano, but Sonim has better reception in critical areas.
It get's funnier with every repetition.
Multipath.
Yes as support for older 2G networks is lowered this is the only bit of advice that makes sense. It was certainly an issue with 2G to 3G but not sure if it is for 3G to 4G.
If reliable signal more important than cost, use a foreign roaming SIM in an unlocked phone - will use the best available network.
What do you mean by after inserting a new sim it deletes your old one from the system? Also what kind of network update does it force through?
Each SIM card is allocated an IMSI number when a mobile number is registered to it, if you replace your SIM card using your same mobile number you get a new IMSI number. Are you saying in your later posts that new cell towers won't pick up your old IMSI? I'll have a look into this when I get back to work as I've never heard of a new cell not allowing access as it doesn't recognise an IMSI allocated to the home network.
SIM replacements are usually done due to lack of diagnostics by customer services it's an easy get out when they can't fix stuff, almost all SIM replacements are a waste of money. Much older SIM cards should be changed as new tech that wasn't around at the time they were made can be affected, ones that are a few years old don't need replacing. You will need a 4G sim to access a 4G network and the same for 3G, this obviously gives access to more of the available network increasing coverage.
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