Infrared transceiver

In debug tools> Infrared monitor, it’s interesting how many raw signals are picked up aim it at the iPhone notch. I wish I could see what I’m picking up beside probably security Face ID OR THE AR camera. (iPhone. 12promax)

:face_with_monocle:

@astra. Are you able to view what that function this reads raw?

Seems to pick up a lot just walking

Yes, that is because infrared light is emitted by the sun, FaceID, iPhone’s camera’s autofocus and even some artificial lights, and the Flipper picks it up sometimes.

Well it sure doesn’t pick up the sun haha

But tons of raw readings just walking, stores. Just wondering if it logs anything

Probably all pointless information tho. Just curious

Thanks

I know, this thread is a few days old. But as I was cached by the phrase “Debug Tools > Infrared Monitor”, I’ve started some tests.

Why do you, @AURORAVIII, think the sunlight isn’t picked up?
If I went outside, nothing around me, there are a lot of random RAW signals. Even more, when I point the IR window towards the street (23°C, no clouds) at drive by cars.
If I point the IR window outside though a closed window, no RAW signals where captures though a long time.

IR light is very weak and shielded by a window (you can’t get tan behind a window). Even if it could go through mysterious path bouncing around.

[…]Since the primary source of infrared radiation is heat or thermal radiation, any object which has a temperature radiates in the infrared. Even objects that we think of as being very cold, such as an ice cube, emit infrared.[…]
Source: NASA - Infrared Light.

Next step: Flipper → Infrared → Learn New remote → Save a bunch of RAW captures … And learn it is just random. That is the reason why we have more or less complex protocols, so the TVs won’t switch on/off all the time by space heat.

It would be interesting if a CCTV is emitting a recognizable pattern, to follow up IR to discover hidden cameras - #4 by darkglamb

Edit:
Interesting reading about the used receiver TSOP-75338: https://www.vishay.com/docs/82495/tsop753.pdf

[…]The TSOP753…series is optimized to suppress almost all
spurious pulses from energy saving lamps like CFLs. AGC3
may also suppress some data signals if continuously
transmitted.[…]

I wonder how to understand page 2, table 3, ‘Supply current’: […]Ev = 40 klx, sunlight[…]
Does this mean: “When the output is static 0.45mA, we are most likely in sunlight”?

Edit2:
After reading the Datasheet, I was even more curios. I’ve hat to walk 4.19 km to test everywhere.
Now we’ve got 28°C, a little cloudy, but much direct sun. The first 3 km, nothing. The Debugging Tools > Infrared display seemed to be frozen (everything around was very hot) … I’ve started to think of a reason. The Flipper is warmer than this morning. Maybe there was a IR source at my walk from the car to my office …
But after roundabout 3 km, the first RAW signal: 43 … Okay. I was just walked through a small forest, and hit the water border of a lake. Along the border I’ve got a plenty more signals (not as much as this morning), until the forest stops and I’ve had to walk at the pier, under the direct sun, again.

So the sensor is sorting out sunlight but only if it is enough. I don’t think the lake is direct involved, maybe because it makes the environment a little colder, so the random IR light is less static.

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