Radios were common in my day and management tended to look the other way as long as you weren’t silly. TVs were a different matter, although some people did have portables. At one mainline box a signalman even got a licence for a TV giving the box as the address, which caused some minor problems when he moved on and didn’t change the address. I think the feeling was that you could concentrate on your work with a radio on in the background, but a TV would take up too large a proportion of your attention.
A hundred years ago or so nothing was allowed except official publications: you should be familiarising yourself with them whenever possible. Then the newspaper became tolerated and it spread to books and magazines. You could sometimes make the odd, possibly unfair, judgements about the signalmen at a particular box by which boxes had a stash of girlie magazines: at least one relief signalman made himself unpopular by destroying any he found as he disapproved of them. (Yes, he did destroy them, not take them home.)
Again, in olden days, it was not uncommon for signalmen, who were literate, doing some odd bits of semi-clerical work between trains. This could be filling out wagon labels, doing the stores requisition, filling in wagon returns, etc. Technically this was the station master’s or clerk’s responsibility, but they might be glad of having a few odd jobs done by somebody else, or the responsibility of one of porters, who might be barely literate. Lamps were sometimes down as the signalman’s responsibility, but on other occasions they might do them, although it might be the staff who actually took them out to the signal. And of course there was the habit of keeping the box highly polished.
The above paragraph is a bit idealised. There would be boxes where the station master would rigidly insist on absolute adherence to the rules, sometimes as how he interpreted them, and bring down the full weight of the railway disciplinary procedures on the tiniest infraction. And there would be signalmen who would only do exactly what was in their contract and wouldn’t lift a finger to help or just sat on the chair looking at the block instruments all through the shift.
A story from long before my time. At one station the staff had been trying to push a trolley up the end ramp of the platform when it ran back and spread itself and its load all over the track, with the result that a major express had to wait while the trolley and contents were removed. The signal box was right by the platform end, but the signalman just watched the staff struggling and made not a move to add his weight.