4 ms·
I would think the stray light from a CRT strobing at 50Hz could be picked up by a photodiode and some amplification. The point of the 'detection' was to just s
by joezydeco 7y ago
I would think the stray light from a CRT strobing at 50Hz could be picked up by a photodiode and some amplification.
The point of the 'detection' was to just see if a TV was in operation and not to see what was being watched.
- marshray 7y agoEver seen the flickering light of a television behind someone's curtains? Ever seen an app that can identify what song is playing?
- tantalor 7y agoToo many false positives: recorded videos, video games, computers
- amaccuish 7y agoPresumably you could compare it to a reference signal, i.e. what is being broadcast right at that moment? Hence the TV aerials on the roof of the vans?
- joezydeco 7y agoThere's a bit too much confusion as to what era the BBC vans might have been using optical means instead of RF means. In the 1950s there wasn't much else on British television sets other than the BBC, right?
- ben_w 7y agoIt doesn’t matter, the offence is “watch TV without a license” (and previously was, I think, “possess a device capable of watching TV”), not specifically the BBC. (iPlayer is not important to this discussion but complicates things a bit).
- deleted 7y ago[deleted]