The answer today indicated that the woman knew that the car was not a local car, in spite of what the salesperson said, because the radio presets were all bad. I don’t know that this necessarily proves anything, since if the battery had been disconnected the radio probably lost any presets.
the way I understood it was that different frequencies would display on the radio, which were not local. A radio that has had the battery disconnected is often sent into a “code” situation and requires a special decode number sequence to allow the radio to play again, Security and anti-theft feature on many cars.
Or, the little old lady who drove it only to school and church may not have ever listened to the radio, and never set the stations. To prove to me that the radio was set in a distant city, I’d need to know what city has all the stations that the radio was set to. There should also be wear on the buttons. And of course, the registration history of the car should show where it was registered.
When I heard the puzzler, I thought the answer would be something about the car being too young for it to have belonged to the teacher while the salesman was in her grade (4th?), but on hearing it again, I guess it didn’t say that she had the car while he was in her class.
I think a better answer would be that it was set to rap and death metal stations.
You’re right, however, this is a very old puzzle (I’ve heard it before) that dates back to the days when auto radio presets were mechanical and therefore persisted when power was removed. Back in the old days – quite possibly before you were born – presets were done with ferrite(?) slugs inside tuning coils.
For an old puzzle, you are right it could be the old fashioned radio, probably AM only, where you set it by pulling out the button to set it mechanically.
My current car (with factory radio) and truck (with replacement radio), if you disconnect the battery overnight, they reset to factory defaults spread across the spectrum. Of course, the factory radio in the car is probably pretty difficult to remove.
Now we just have to know whether the radio was ever used…