A round chassis

[Refugee]

There are no ultrasound parts in it.
Those sonic cat scare things don't work anyway. The one of those I do have is a reduced power cattle fence over the seedlings and it works well by reprogramming that the seed beds belong to me.
It is lit though.

[pwdrive]

Looks like it might be fixed to a ceiling?
There's 40 of something in 20 pairs arranged to cover 360 degrees.
Individually mounted on heat sinks?
Looks like diffuser lenses fitted?
The inner pairs are clearly numbered.
Sequential?
As to what it is, not sure...

Lawrence.

[Refugee]

We are getting closer.
It is indeed fixed to a ceiling.

[pwdrive]

Emit, reflect, sense.
?

Lawrence.

[pwdrive]

Would the chassis be an old speaker chassis?

Lawrence.

[Refugee]

It is not an old speaker chassis.
It does emit though.
So are we ready to identify what the chassis was before I recycled it for this project?

[pwdrive]

Vacume cleaner, part thereof?

Lawrence.

[Skywave]

Three guesses:
1. Carbon monoxide or smoke detector;
2. Burglar / intruder sensor / alarm;
3. Doorbell.

Al.

[Refugee]

The original part that now makes up the chassis is 585mm across ans is a little large to be any of the above items in its previous life.
We are getting a little closer to the target device though.

[pwdrive]

Gosh that's a big chassis....
Does it emit visible light?
Is there a counter chip on that board?

Lawrence.