Since the start of the New Year, I've noticed that my phone (Galaxy S5) goes into 4G mode in some parts of the city, despite the fact that I have a 3G sim card. Likewise, my internet package is 3G. I've run a speed test when I've seen this happen, and the speeds are definitely 4G (e.g. 17 Mb down, 11 up) - my 3G is always much slower than that. This is with True Move.

Has anyone else noticed this? Is this just some kind of glitch or is True Move doing some kind of automatic migration from 3G to 4G?

Thanks,

HeyNow

I'm not sure there is such a thing as a 3G sim. If your phone is compatible and the network allows it, you'll get 4G.

Posted Yesterday, 21:17

Since the start of the New Year, I've noticed that my phone (Galaxy S5) goes into 4G mode in some parts of the city, despite the fact that I have a 3G sim card. Likewise, my internet package is 3G. I've run a speed test when I've seen this happen, and the speeds are definitely 4G (e.g. 17 Mb down, 11 up) - my 3G is always much slower than that. This is with True Move.

Has anyone else noticed this? Is this just some kind of glitch or is True Move doing some kind of automatic migration from 3G to 4G?

Thanks,

HeyNow

I'm not sure there is such a thing as a 3G sim. If your phone is compatible and the network allows it, you'll get 4G.

Technically, your SIM card should advise the phone or device what frequencies (bands), networks, and roaming partners are available to you as a 'subscriber'. So a 4G SIM should work in a 3G Phone, and a current 3G SIM should also be 4G network aware.

But there are other mitigating issues in play here in Thailand.

The latest issue is the shutdown and mobile provider reassignment on the 900 and 1800 frequencies.

While small changes to the SIM can be done OTA (Over The Air), since this involves new frequencies (bands) and technologies then TRUE and AIS are better off just swapping out the current SIMs with newer SIMs as of the December change-over.

I believe another reason there is an issue with 3G vs 4G SIM cards in Thailand is due to a subsidiary concession vs license fee each company has to pay to the government. When they swap out the SIM card of your phone, GSM for 3G, or 3G for 4G, they are also switching you to another subsidiary with a different government billing rate. The customer doesn't see this ...well, except when their account loses legacy benefits.

And don't expect your 3G subscription to give you faster 4G/LTE downloads on an LTE network. They're going to throttle your LTE connection speed to match the subscription speed rate if there is a difference between 3G and 4G pricing.

When AIS turned on their new 4G network in December some people were sent a text allowing them to access the new LTE network via their LTE phone and current '3G' SIM (probably updated OTA), while others, like ME, were told to visit an AIS shop and have their 4-year-old 3G SIM swapped out for a new '4G' SIM. I haven't done it yet as I don't live close enough to any 4G towers to take advantage of the upgrade.

The licensing of frequencies (mobile and TV) in Thailand sure seems like a mess and never ending law suits.

No such things as a 4g sim, like SoiBiker said if phone allows 4g you should get 4g.

Saying that telco's in thailand have a habit of bidding for licenses in newly created companies like Dtac/Trinet, True Move/Truemove-H and sometimes they make you switch sim cars to get the new network.