[PoachedSausage]

I'm curious as to UK end of the link now. I would guess somewhere on the hills around London to get line of sight for a microwave link down to the city.

Having just checked the Ofcom Spectrum Information System [0], it does not appear that they could have a transmitter for the opposite direction due to the frequency allocation to MoD and Amateur. Maybe they have a contract with the shortwave broadcasters to embed trading data into their broadcasts.

[0] https://www.ofcom.org.uk/spectrum/information/spectrum-infor...