[Spencer]

The Radio 5 feed was used as the backup (RBS) source for the AM transmitters, so the network operated on a delay to match the satellite so that if one transmitters went onto that backup it would stay in sync with others on the same frequency.

This meant that things like radiocar contributions couldn't use the typical off-air cue feed for the reporter or guest's headphones.

Would they have often used an off air cue in a radio car? My experience of BBC LR radio cars was they had a clean feed from the studio with talkback. It’d also surely be unwise to give guests a feed in which they’d hear themselves coming back in their ears, as if you’re not used to it, it can be very off-putting.