I want to enter the world of 433mhz lol but I am a bit lost.
I want to set up an alarm system with door/window sensors and a siren that can be controlled and read by HA
Every posts and tutorials on the web suggest to use sonoff RF bridge; the old one which is no longer available.
What gateway can I use instead that is compatible with home assistant?
Do the alarm panels on aliexpress
ex. https://www.aliexpress.com/item/1005005099651246.html
has an exposed API so that I can read sensors readings or trigger the siren with http requests for example and interact with HA?
That is usually the issue with RF devices. They might not be that controllable or readable.
RF is proprietary standards, so you start with a white paper and have to figure out the standard used yourself.
Besides that you are looking into tackling an alarm systems which often will use rolling codes, so makes them hard to be hacked with a learning remote, but this also makes them equally hard to implement into any system that do not have the algorithm for the rolling codes.
Look into a standard that is supported by HA, like Zigbee, or a system that is already with an API to integrate with.
thx for ur reply. Yeah I am finding that 433mhz seems complicated as opposed to zigbee. I was leaning towards 433mhz because the sensors are much cheaper than zigbee one.
side question : some zigbee sensors say they work only with a tuya zigbee gateway. Some even mention it won’t work with zigbee gateway but tuya zigbee
is tuya zigbee and zigbee different?
Zigbee is a communication standard for IoT, but it is not completely required to follow it strictly, which makes it flexible, but also open to strange implementations.
I have no Tuya Devices, except a few, that I knew beforehand I could reflash with open source firmware, which I have done.
Some like Tuya, I do not, but I just resent the products on a hunch, so others might provide some more info on the inter-interoperability of general Zigbee and Tuya Zigbee.
I have 2 Rflink with ESPRFLink added, and 2 Sonoff Rf Bridge flashed with OpenMQTTGateway. The Sonoffs are limited in what protocols they can decode.
An Rflink can be easily built for €20 to €25, and much more versatile then the Sonoff.
Be careful with those kerui door/windows sensors, they only support open notification, there is no close notification ! There are 433Mhz door/window sensors from digoo and blitzwolf that support both open en close notification.
Broadlink pro is decent for sending out 433 Mhz signal, but not for receiving data. It only receives data when in learning mode, not during normal operations.
This is hard to say, because it depends on your building and the stuff inside it and other electrical devices that can cause noise.
You might need multiple RF transceivers to get good enough coverage and you need to control the signals on the RF transceivers, so the signal is not handled multiple times.
Zigbee is a mesh network, so it can be extended with smart plugs, bulbs and other mains powered devices, which act as routers (the zigbee word for an extender) to expand the coverage.
I think you need to be aware of what you are going into by choosing RF devices for your project.
You might get your RF transceiver up and running, but when you receive a signal from one of your devices that says “State:H” then you need to be able to understand that to react to it.
You also need to be able to know what other states or messages you can get, so you do not end up in a situation with an unknown, but important state.
The problem with “State:H” is that anybody with a RF transceiver close by can capture and transmit this code and if it means disarm the alarm, then you are f***ed!
The countermesasure to this is to use rolling codes, which will send “Rabbit” instead and the next time it will send “Bear” and then “Frying Pan” and they are all the same message.
Once Rabbit is used, then it can’t be used again and same with Bear and so on.
This means when you before could just figure out with State:H meant, then you now have to figure that out maybe like 1024 or many more times and the same for State:Y and so on.
So if the devices are using rolling codes, then you need the algorithm or you are lost or the devices need to be made by the same vendor with this rolling codes already installed.
When using RF devices, then understand that many of them is just one way communication, so they report in when they want and there is often no way of getting a message the other way.
That means a door sensor will report when the window is being opened or closed or when the battery is low, but if you missed that message, then there is often no way of asking the sensor to resend its last message to get to know the state.
Some devices from the same manufacturer have an intelligence built into the devices that allow the devices to also listen for messages the other way, but this devices are more expensive, because the devices then need to be able to both transmit and receive and because there is a logic that have to be followed, then the devices can typically not be mixed with other manufacturers brands or even other product lines from the same manufacturer.
This dependency on a certain manufacturers specific product line means that you need to buy up a reserve or be really sure that the product line is still produced in the future, because standing with a broken door sensor 1 year later and realizing you have to add whole other system in to replace that single sensor is a hard one to swallow.
I would not buy a RF433 Mhz alarm panel, 99% chance you never get it to work with HA. Door/window sensors, PIR’s etc are OK, but it is because I had them long time before I started with HA that I use them. If buying new, I go for Zigbee.
thx. It seems that it can easily turn into a nightmare to configure and maintain.
I think I might look into zigbee instead as you and everyone has suggested