Hello Jim,
That is indeed weird. Was it ever used in civilian apps? Then there might be a higher chance of finding something at places such as universities. There had been a number of "AM radio on a chip" ICs but most have gone to lala-land. Some might still be used in local pagers or hearing wands.
But it's not unheard of. Once I had to mimic the behavior of a chip as measured on the outside but decided to do it in discretes (cheaper). This was not reverse engineering in a bad sense but it was for the owners of the design.
Regards, Joerg
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