The modern day PIR incorporates a multitude of features and is available in many different versions. Give two examples of these features.

im assuming this is about the difference between dual edge and quad edge elements. Can't see its logic vs pulse count. You could go leftfield and add alarmcom fuzzy logic ir220 into it

I was thinking more about anti-masking ? or I'm Wrong ?

I was thinking about how they work, am might be part of it but am isn't anything to do with how they detect movement, well not at more than a few cm

I've just reread yes it probably is that basic

Ok then so AM is one and what would be the other one having in mind that it will be something basic ?

id go thick and say pet tolerance

hahaha I even didn't think that it is gonna be that simple  But yeah I will go for it  

Temperature compensation?

you are asking a load of questions over a number of posts would it not be easier to lump them into one post?

I have done that Sir  and I was asked to put them separately in single posts by my Master james.wilson 

I know.