Suggestion to buy SIM800L

I would use a SIM800 to send SMS messages when trigger start in Home Assistant: anyone have experience on it?

I found these types:

  • ch340k v15
  • ch9102 v1.4
  • cp2104 v1.4

anyone can give suggestion on which SIM800 to buy? any other suggestions?

I do. Using a esp paired with a cheap sim800l and esphome on is it capable of doing this job.

No ideas what this types are? Any links? There are ready made esp boards which host a sim800 modem so no need to wire things together yourself.

esphome. It allows you to directly send messages via HA service :point_down:

Please see this link:

€ 3,01 10% Off | LILYGO TTGO t-call V1.4 / V1.5 ESP32 modulo Wireless SIM Antenna SIM Card modulo SIM800L

You have some suggestion when using HA+ESP+SIM800?

This is a ready made board which combines a esp32 with a sim800 module. Should be very easy to get this working with HA.

Install the esphome add-on in HA and create a new node with the wizard (choose the generic esp32 module) and add the yaml code presented in the docs:

If esphome is new to check out the getting started guide:

Which power supply do you used for SIM800L?

Any issue with radio signal strength?

It’s written in the linked docs (very prominent in a box on top :warning:) what power requirements the module has. :page_facing_up:

No - but that depends heavily where you are and the distance/obstacles to the next radio tower :tokyo_tower:

Be very careful with the cheap as dirt modules linked above. I had one similar to those. It worked at first, then suddenly died. I went to check what the problem was, went into the attic where it was located (better signal) and was greeted with an intense smell of burnt electronics. The module was heating up like crazy with the pcb starting to look charred. Thankfully I was around when it happened. No idea how bad things would have gone if I was away / sleeping.

At that price point there is a good chance that these chips are counterfeit or scrap ware that didn’t make the qa tests. I ended up replacing it by a SIM800 module by waveshare. Bit more expensive (~20€) but at least the chance for it to burn down my house are lower… I also added a slow acting fuse into the power supply line. If it pulls more than an amp for more than a few seconds, the fuse blows.

Which module you say could have problems?

SIM800L single module or SIM800L+ESP32?

The small red ones. And possibly others too, there are many shady ones on Ali/ebay/Amazon. No idea about that ESP combined thing, I don’t use ESP’s.

Sidenote, if you want to reply to someone, then you need to hit the reply button under that users’ post, not the global thread reply button. Otherwise the user won’t be notified. I just stumbled over your reply by accident.

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