Brian Gaff wrote

You can get readers for the chips, but I do not know the range. I'd look
at those and see if they generate a signal of some sort. I saw something
a couple of years go on Country file where a farmer had an automated
cattle sorter that used rfid to move a metal grille so certain animals
went one way and others the other way.

And plenty of automated dairys read the chip on the
cow and tailor the feed to the individual animal while
its milked and weigh each animal and record that too.

"Adrian Caspersz" wrote in message
...
On 06/08/2019 18:53, ARW wrote:
Any recommendations for one?

Two cats and the owner wants no aliens in the house.


There was someone who used to spam newsgroups with such a product
sometime ago. So not a recommendation no matter what that is.

I'd go DIY, some sort of two-factor authentication.

i.e.
1. machine learning, so that what looks like a cat is identified as being
a cat,
2. having a microchip.

A laser to vaporise subjects that fail that would be a natural upgrade.

--
Adrian C