Cat doors

Hi,

I am in the market for a new cat door. I installed a simple cat door a couple of years ago. It is
not electronic or magnetic - just a typical plastic swinging door that the cat opens by pushing
against it.

The problem is that raccoons have discovered the opening and like to come in to dine on cat food
while we sleep. We have decided to install a more modern door, but have had little luck finding
exactly what we need.

It appears there are 2 basic door types: electronic and magnetic. In either type, the cat wears a
device on its collar that unlocks the cat door. We purchased a magnetic door but found that the
magnet our cat would have to wear on her collar was enormous. She would rip her collar off in no time.

So, we are now looking at electronic/Infrared doors. There are many to choose from and we are
wondering if anyone has had any experience with them. Pros/cons on any particular brands/models.

Also, this needs to be a wall-mountable door. As a carpenter I have no problem constructing a
tunnel to connect the two sides of the door, but most cat doors we have found are strictly designed
to be installed in a door.

Any thoughts/ideas?

--Steve