MTN Dual sim: Please Explain

Cube

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Can anyone explain what the benefits are of having a dual sim compared to having a calls diverted to a number when the original number dialled is not answered?

Spesifically, I need to know about the costs involved. I know you have to buy a second sim and and there's possibly an activation fee, but do you pay for the divertion of a call from one terminal to another as you would when having a normal call divert option activated on your phone.

If so, what's the point of having a dual sim setup?

I have a big, heavy smartphone (that i'd like to keep stationary) that is used mainly for data applications (internet, document distribution, e-mail, etc on the pc) and a smaller, less capable flip phone for everyday phone calling.

Any info would help as the mtn site is not that accurate, and I can't access mtnsp.co.za via the gprs connection!
 
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the dual sim does not involve call costs.
Efectivley the last handset to login to the network becomes your active phone and is the one that receives the calls. You can get into a mess where the wrong phone is active.

But from what you say you don't want to use the big smartphone for calls, just data. In that event it may be a pain to use the dual sim.

MTN should issue data SIMs that can only be used for data as a 2nd sim on an existing contract. That would be a handy option.
 
So you mean to say that your primary sim is the one last activated? I had hoped that their status remains the same regardless of when they are connected and disconnected from the network, ie set by the SP. Does that mean that the status of the device changes whenever you switch the phone on or off, for example:

Let's say Device A is primary and Device B is secondary.
I then switch of Device A and Device B becomes the primary?

I can see that being a problem. Luckily I hardly ever switch either off.

I do sometimes make calls on the smartphone (when I'm too lazy to reach for the other one).
 
What I learnt about dual sim...

OK, so this is what I found out about Dualsim (on a trial and error basis). Please correct me if I am wrong anywhere:



  1. With Dualsim both cards can make calls at the same time on different devices.
  2. The secondary sim cannot sms (understandable, I suppose)
  3. The secondary sim can use gprs, 3g (although mtn helpline (808) told me it can't. Yet I am utilizing it now)
  4. The secondary sim does not appear to have caller ID (I've asked for it to be switched on on the second sim, and no change so far)
  5. The primary device id stays put. It doesn't appear to change as I thought above. Switching on an off makes no difference.

And for some reason the secondary device keeps telling me the data connection needs to be terminated for the mms to come through. The connection is off and as far as I know no mms has been sent to me recently. Anyway it should come through on the primary device, shouldn't it? I think I'll switch cards and see what happens.

I'll add more when I find more... Hope this is usefull to anyone else...
 
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My experience as follows:

1) If original SIM is "on", it will receive incoming calls .. second SIM does not ring.
2) If you are talking on primary SIM, incoming call diverted to secondary.
3) Both can initiate calls, even simultaneously.
4) Second SIM has no SMS, CLI.
5) By default, scond SIM has no international calls or roaming. I got them to activate international calls, but roaming still does not work.
6) I can set my primary Sony Ericcson P990i to "accept no calls", and all are then diverted to secondary, even though primary is "on" for SMS, etc.
7) Dual SIM is intended for a fixed car phone, although it works in handsets.
 
Hi
Here is how dual SIMS work :

a. When you purchase a SIM, it has three MSISDN (telephone) numbers assigned to it - one for Voice (normally the cell number you use), one for Fax, and one for data.

b. When you activate a dual SIM, you will receive a SIM with two MSISDN numbers allocated - one for voice, and one for data. (If you enable call ID sending when you use this SIM, you will be able to see what the number assigned to it is and people will be able to call you directly on this number).

c. When you turn your first SIM off, the network routes calls bound for this MSISDN number to your second MSISDN number. Turn off can mean that your phone is physically turned off, or diverts are set to "always".

d. If you need to activate your data on the second sim, you will need to get the MSISDN number for that SIM and have it provisioned on the relevant APN on the network's data network.

e. You can SMS from the second SIM provided the number is provisioned on the SMS gateway - again - you need to get the MSISDN number for it first. (you can also SMS straight to the second number)

f. The idea of the second SIM is that nobody gets the MSISDN number for it, because that way you are in effect getting a "free" second line subscribtion, especially considering that you can take calls directly onto that number. Normally if the networks figure out that you are bypassing the billing by doing this, they will block the MSISDN. (although I have only ever heard of this happening once). So, the networks will set the CLI sending to off automatically. But - you can force your phone to send the number - I cant remember off the top of my head what the command is but I remember seeing it in the user manual that arrived with my phone from MTN. I can look it up if you want... I force it from my handset (because my handset allows me to :D )
Hope this helps!
Cheers ~
ScrnScrm
 
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