The UK’s Radio Times listings magazine is available online from 1923 to 2009. The magazine was once the nation’s vital weekly TV and radio listings title. When last noted on the JURN blog, back in 2014, I think the new online listings had only extended as far back as the 1960s. Possibly there were also no thumbnail cover-scans back in 2014, but there are now.
You can’t actually click through to hear programmes, due to a combination of the trades unions and the surprising and very regrettable lack of tape archives. So if you do spot gems in the listings, like the 26-part radio history of The British Seafarer (1980) with music and FX by the Radiophonic Workshop… it’s gone forever.