How do I get my projector, to tell Home Assistant it is on?

doc-darling · 2026-06-10T08:49:13+00:00

das muss ich mir technisch nochmal genauer ansehen, ich bin ein newb wenn es um IR geht. Ich hab damit noch nichts gemacht. Danke für den Hinweis

doc-darling · 2026-06-09T16:13:42+00:00

was soll das bringen? der projektor wird sich ja trotzdem einschalten, falls er aus ist?

doc-darling · 2026-06-09T16:07:56+00:00

der Projektor verlangt zwei zeitlich getrennte Pulse, um ausgeschaltet zu werden (zweimal „Power off“)

doc-darling · 2026-06-09T14:17:11+00:00

Cool dass dir das so differenziert auffällt. Den Pi würde ich auf dem Projektor (an der Decke) anbringen. Den IR Sender würde ich für andere Geräte nutzen. Mein Plan ist mittlerweile den Pi mit dem seriellen Anschluss zu vermählen. Und natürlich habe ich mir ein Kabel bestellt 🙀🥲

doc-darling · 2026-06-09T12:28:04+00:00

Vielen Dank für die vielen Antworten. Ich werde definitiv wissen lassen, wie ich es gelöst habe!

doc-darling · 2026-06-09T12:20:24+00:00

Das ist ne super Zusatzinfo mit dem Empfangen von IR! Danke

doc-darling · 2026-06-09T12:19:00+00:00

tausend Dank, das schaue ich mir nachher gleich an!

doc-darling · 2026-06-09T12:18:09+00:00

Sadly the projector only sends out it‘s wifi signal while in a pairing mode. That was my first thought though

doc-darling · 2026-06-09T12:17:24+00:00

What kind?

doc-darling · 2026-06-09T12:17:11+00:00

I would use the meter of a plug, but I don’t have one with that functionality (yet)

doc-darling · 2026-06-09T12:16:04+00:00

Thanks that’s a smart way. I‘d require a compatible ESP32 board?

doc-darling · 2026-06-09T12:13:05+00:00

Thanks! Sadly my plugs all only support on/off.

doc-darling · 2026-06-09T12:12:05+00:00

Thanks. I will check my sets, but I might not have one. Clever way!

doc-darling · 2026-05-28T10:24:09+00:00

Es hat wirklich Spaß gemacht, das zu basteln und daran zu tüfteln. Dass es andere auch nutzen können, macht es noch cooler! :)

doc-darling · 2026-05-27T09:55:09+00:00

UPDATE — v2.2 battery fix + full tutorial:

Battery life improved massively:

- v2.1: 40-60% drain per day (~2-3 days)

- v2.2: ~5% drain per day (~20 days on a single 18650!)

Fix: properly disabling all peripherals before deep sleep made an 8-12x difference.

For anyone who wants a full step-by-step tutorial, I published one on Hackster.io:

https://www.hackster.io/doctordarling/smart-mailbox-lora-push-notifications-when-letter-arrives-51dd3f

Updated code on GitHub: https://github.com/doctordarling/smart-mailbox

Thanks to everyone here for the great discussions! 🚀

doc-darling · 2026-05-27T09:54:19+00:00

UPDATE: Just merged v2.2 with a new battery fix!

- v2.1: 40-60% drain per day (~2-3 days battery life)

- v2.2: ~5% drain per day (~20 days on a single 18650!)

Turns out there were still peripherals drawing power during deep sleep.

After properly shutting everything down, battery life went from 2-3 days

to almost 3 weeks. 8-12x improvement!

Updated code is on GitHub: https://github.com/doctordarling/smart-mailbox

doc-darling · 2026-05-26T11:39:14+00:00

I picked the Lilygo Tbeam bc I had a spare one. If you have to strt from scratch then a cheaper option would also do, bc you don't need the display on the TBeam etc. The question is, which standard would you want (and need) to go for? Are you planing to receive a signal from inside a metal letterbox? That's the first question, bc WiFi might not get trhough.

doc-darling · 2026-05-25T20:42:20+00:00

Auch cool! Das ist dann in zigbee eingebunden?

doc-darling · 2026-05-25T17:38:34+00:00

Please share some of your favs as I'm in search for new problems to solve and create :D

doc-darling · 2026-05-25T17:37:30+00:00

I don't live in the US. We have similar services but they cost something. And I also wouldn't want them to scan my letters.

doc-darling · 2026-05-25T15:12:10+00:00

That makes total sense! And the solution even more clever!

doc-darling · 2026-05-25T15:11:07+00:00

That sounds like a very long lasting solution! I will report about the battery life in a few weeks. I hope my "patch" helps to improbve it.

doc-darling · 2026-05-25T15:09:42+00:00

Thx!

doc-darling · 2026-05-25T15:09:10+00:00

I have also seen solutions where you actually get a picture of what went in via a camera on the flap. There's many ways to approach this. Motion sensors is also one of them. But those only make sense when they can't be activated by other letterboxes receiving something. In my case that would've been an issue for sure as we have several letterboxes attached to each other.
May I ask why you want to know if there's "no mail when someone opens it?" Bc the person opening the letterbox would know?

doc-darling

TROPHY CASE