On 16 Sep 2005 01:08:10 GMT, (Jay Masino)
wrote in ::

I don't think the transponders actually check for warmth.

A transponder contains what is termed a Crystal Oven. This is a small
chamber in which there is a heating element and a quartz crystal used
to determine the transponder's transmission frequency. It takes time
for the oven to bring the crystal up to the specific temperature to
which it is set. If the oven were not thermostatically controlled, it
would not be able to provide a stable reference frequency at all
ambient temperatures in which the transponder operates.