Thanh
29-09-2003, 10:52 AM
Hello :)
So i got this 5130, which is a GSM-1800 ONLY phone. I use a modified flash file, which still keeps it being a GSM-1800 ONLY, i guess :)
The SIM in that phone is from a GSM-900 provider (Thailand, "GSM advance" or "AIS", network codes 520-01) and the network actually USED is "DPC 1800" or "Hello", codes 520-18. This is possible because AIS bought that company a while ago and the two networks can roam with each other.
Yet on saturday,the following happened:
me and my boyfriend, who is using that 5130 at the moment, went to Mahboonkrong center in Bangkok. There, in the food court on the 7th floor, he wanted to make a phonecall, which he did. And after it, he placed the phone on the table, looked at it and then asked me "what the heck is that???".
I looked at the phone, and instead of the operator logo it displayed "TH 01". I know what that means - the phone seemed to have logged in to the AIS network, which SIM card is inserted. yet - AIS is GSM-900!
I took the phone, cranked up net monitor and went to investigate. And i found that in fact the phone was logged in to that network despite the fact it is GSM-900..!
A look out of the window (it was dark) made me discover the AIS tower just about 15 meters apart at the edge of the building. And i tought "maybe the signal is SOOOO strong that the phone "runs" on a harmonic wave" or something like that, and i kept the phone on the way home. But it hanged on to that network untill we reached our apartment, where in the lift it lost signal and at the room it logged back into the usual "DPC-1800" which then displayed the operator logo.
Now i did a phone call to AIS and demanded to speak with an engineer (which to my surprise was possible!) and that guy not only spoke english but also could assure me that AIS "nowhere in the entire country" uses GSM 1800 in it's own network!
Now, what on earth can cause a 1800-only phone not only to catch, but also to hang on to a 900 network??? This network (TH 01, or 520-01) never comes up on a manual network search.......
Or was there some sort of "frequency hop" caused by the athmosphere? I can remember this strange situation over a year ago, then with a 6510, where at my offce on a sunny day i had the name "Itineris" on my display, instead of my logo.... knowing Itineris as a french network, i was puzzled. I know that electro-magnetic waves can be reflected at the ionosphere, which enabled me as a CB-radio operator to have DX conversations, but normally a frequency of 900 MHz or let alone 1800 MHz can't be reflected anymore, and specially not if it is over thousands of kilometers! yet still my phone cought that net for almost 25 minutes, i wasn't able to make a call on it (beep beep beep) but i could send a SMS which got delievered with almost 3 hours delay!
Can anyone tell me what that was with my 5130..? I am thankfull for any information......
Kind regards......
Thanh
So i got this 5130, which is a GSM-1800 ONLY phone. I use a modified flash file, which still keeps it being a GSM-1800 ONLY, i guess :)
The SIM in that phone is from a GSM-900 provider (Thailand, "GSM advance" or "AIS", network codes 520-01) and the network actually USED is "DPC 1800" or "Hello", codes 520-18. This is possible because AIS bought that company a while ago and the two networks can roam with each other.
Yet on saturday,the following happened:
me and my boyfriend, who is using that 5130 at the moment, went to Mahboonkrong center in Bangkok. There, in the food court on the 7th floor, he wanted to make a phonecall, which he did. And after it, he placed the phone on the table, looked at it and then asked me "what the heck is that???".
I looked at the phone, and instead of the operator logo it displayed "TH 01". I know what that means - the phone seemed to have logged in to the AIS network, which SIM card is inserted. yet - AIS is GSM-900!
I took the phone, cranked up net monitor and went to investigate. And i found that in fact the phone was logged in to that network despite the fact it is GSM-900..!
A look out of the window (it was dark) made me discover the AIS tower just about 15 meters apart at the edge of the building. And i tought "maybe the signal is SOOOO strong that the phone "runs" on a harmonic wave" or something like that, and i kept the phone on the way home. But it hanged on to that network untill we reached our apartment, where in the lift it lost signal and at the room it logged back into the usual "DPC-1800" which then displayed the operator logo.
Now i did a phone call to AIS and demanded to speak with an engineer (which to my surprise was possible!) and that guy not only spoke english but also could assure me that AIS "nowhere in the entire country" uses GSM 1800 in it's own network!
Now, what on earth can cause a 1800-only phone not only to catch, but also to hang on to a 900 network??? This network (TH 01, or 520-01) never comes up on a manual network search.......
Or was there some sort of "frequency hop" caused by the athmosphere? I can remember this strange situation over a year ago, then with a 6510, where at my offce on a sunny day i had the name "Itineris" on my display, instead of my logo.... knowing Itineris as a french network, i was puzzled. I know that electro-magnetic waves can be reflected at the ionosphere, which enabled me as a CB-radio operator to have DX conversations, but normally a frequency of 900 MHz or let alone 1800 MHz can't be reflected anymore, and specially not if it is over thousands of kilometers! yet still my phone cought that net for almost 25 minutes, i wasn't able to make a call on it (beep beep beep) but i could send a SMS which got delievered with almost 3 hours delay!
Can anyone tell me what that was with my 5130..? I am thankfull for any information......
Kind regards......
Thanh