Before emigrating to Matlock in the 80's I was B.R.Signals & Telecom's, Southern region. Redhill. on occasion covering Three-Bridges. ( including Gatwick Airport).
The 'Controll computer, including Full shutdown trip-wire under the flightpath' ,was run on a punched tape.
Repair at night (when called out in the wee hours) was sellotape and re-punch with a biro!
Hi Tech or wot? :ohmygod: