On 29/11/2019 16:09, Rod Speed wrote:
I was going to investigate a(n invisible?) break-beam sort
of device that could be set higher than most ground
dwelling creatures

Thats sort of what I am trying to achieve using the PIR.
In the back yard a want to cover the area if someone gets close to my
patio or widows and at the front when someone comes down the path I get
a ding dong from the receiver in house. So narrow cover would be ideal.

At the moment I have tried blocking areas of the lense with strips of
insulating tape but I keep getting random soundings and I know nothing
is out there to set it off.

I have no electronic knowledge which is not helping. There are more
expensive `systems` on the market but I dont want to invest if it aint
going to work.