AAAksherly... whilst it is true that O2 (nee Cellnet) and Vodafone are the original 900 MHz operators and T-Mobile (nee One2One or whatever the spelling was) and Orange started life on a then completely different 1800 MHz network, I have it on good authority that O2 and Vodafone utilise 1800 MHz transmitters to fill in the reception gaps.
My early car phone (as in 'screwed to the car') worked on 900 MHz only. My first digital (and portable) phone (Nokia!) worked on 900 MHz only. The first Nokia that worked in North America on this awkwardly different frequency (1900 MHz) was only dual-band: 900 and 1900 MHz, manually switchable. It was Motorola that came out with the first popular phone that switched automatically and then Nokia came out with a tri-band
900/1800/1900. The 6310i is an iconic example. I have still have one (fits into my car cradle) and so do many other people.
It might be that Orange and T-Mobile (& anybody piggy-backing off them like Virgin and Tesco mobile) still only have 1800 MHz transmitters but it would surprise me slightly.
AFAIK all phones sold in the UK (all Europe?) are at least dual-band
900/1800. All digital, of course. As somebody else observed, analogue has been switched off here.
Still, a 1998 phone could still be subject to some compatibility problems.
I hope it works for you. You might also have to do a software update. An old phone can't necessarily handle a modern SIM card.
The reason the phone shows "Cellnet" in receipt of the O2 signal is that is how it is 'hard-programmed'. Dunno what would happen with a Vodafone signal. Probably will show "Vodafone" since the company hasn't changed its name since 1998.
DAS
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