Also, the TV didn’t just send the currently-tuned channel ‘down’ the chain, it also allowed connected devices to inject their own, synced, video back into the TV, so you could be watching a show on BBC1, say, and the VCR could overlay a box in the top-right corner letting you know it had started a scheduled recording off Channel 4. Or, if you used a device like a Selectavision, if you tuned into a scrambled channel the Selectavision would notice, decode it, and send the descrambled version back up to the TV, all without the user realising it. Those clever Frenchies.
Also, the TV didn’t just send the currently-tuned channel ‘down’ the chain, it also allowed connected devices to inject their own, synced, video back into the TV, so you could be watching a show on BBC1, say, and the VCR could overlay a box in the top-right corner letting you know it had started a scheduled recording off Channel 4. Or, if you used a device like a Selectavision, if you tuned into a scrambled channel the Selectavision would notice, decode it, and send the descrambled version back up to the TV, all without the user realising it. Those clever Frenchies.