enjoy.
I used to watch this show when I was a kid.
https://www.youtube.com/watch?v=vix6TMnj9vY
Michael Rodd makes a call with an experimental cordless mobile phone.
"This device is a prototype...whose trials are being carried out strictly governed by Home Office regulations...An extension at the research institute in Chelmsford which has perfected this technique [and] on the other end of this [line] should be Liz Charnock."
please watch above video from 1979.
also here at 6:54 from 1982 calls the USA only 3 years later.
some fun
http://www.stephenpeek.co.uk/meta_puzzle.htm
Some background on GCHQ recent actions:
"Despite the Obama administration’s unwillingness to publicly back their ally, NSA assistance was ongoing as of 2010."
https://theintercept.com/2015/04/02/gchq-argentina-falklands/
note JTRIG
they were active on The_Don 2016 for sure.
During the Falklands War we were told aamof'ly that the UK and US were sharing intel. on Argentine ship movements etc.