Sonoff ZBBridge - Sonoff Zigbee Bridge from Itead

Hardware
143

Hi your link says out of stock?

144

Yea, the few only lasted a day or so. I will have more soon - sign up for an email when they come. Iā€™m waiting on a pcb order that took longer than usual. The parts are in transit now should hopefully arrive later this week.

145

Can you ship outside US?

146

Yes - Iā€™ve been doing this via US Postal Service ā€œinternational first class parcelā€ delivery is 1-3+ weeks. Prices range ~$14-19 depending on destination.

Iā€™ve seen some packages make it to destination in 4-5 days (London, UK) others sit waiting for a flight in the New Jersey/New York area for a week or more. Or seem to drop off tracking as they pass on to other postal systems.

147

thank you. Iā€™ve registered. Weā€™ll wait for the notification.

1 Like
148

This inexpensive Zigbee 3.0 USB dongle from ITead is now available for $6.99 (US) directly from China:

https://www.itead.cc/zigbee-3-0-usb-dongle.html

Looks like a limited first production run so maybe not get greedy and perhaps let developers order first?

149

Good to know this USB Zigbee 3.0 dongle is now available, but I expect some important disadvantages:

  • The antenna / radio design is probably not delivering a satisfying Zigbee RF coverage within a medium sized house. This may cause connectivity loss to sensors or the need for 1 or more Zigbee repeaters in the house.
    These issues have been described earlier in this thread.

  • Also, this USB dongle usually needs to be plugged into your computer running your HA software. This is not ideal if you want to install your Zigbee transceiver at a centrally located place in your house, connected hardwired to a LAN.

150

But that is how Zigbee is designed to work. Non-router devices should really not connect directly. See:

Also note that coordinator have limits on directly connected children devices, so be sure to use routers!

151

Yes, but it should not be the intention to install (mains powered) zigbee devices in a network solely for the Zigbee repeater function and improve Zigbee coverage around the house.

I would expect from a decent Zigbee coordinator at least a decent antenna design (incl gains) and Zigbee RF range around it. And preferably with a UTP/LAN connection.

152

This inexpensive ITead Zigbee 3.0 USB dongle is very cheap for what you get, but clearly has its limitations in practical use for a mid-sized or larger house / outdoor coverage.

153

Yes it really is so. Please read ZHA documentation which tries to explain the purpose of router devices:

https://www.home-assistant.io/integrations/zha/#using-router-devices

Zigbee is designed to take advantage of network mesh function to extend range + coverage.

This is by design as a solution to the fact that Zigbee devices are low-power and operate at 2.4GHz so their signal penetration through walls is bad. Creating a network mesh with Zigbee routers is how you are supposed to extend range and coverage, at least if talking about low-powered Zigbee devices for home automation.

As a general rule, you want to have a backbone with a few good/stable always-on devices acting as Zigbee Router spread around your house that makes up the core of your Zigbee network mesh.

As an example; IKEA even bundled a Zigbee signal repeater with its battery operated window blinds.

Yes everyone buying a Zigbee coordinator device should try understand that each implementation will be different, and a great quality fully positional external antenna on a Zigbee dongle can compensate for a lot so everyone should keep that too in mind when comparing implementations with onboard circuit-board antenna versus SMA-connector or IPEX/uFL + a high-quality external antenna as well as several choices of USB-to-Serial/UART chips when it comes to USB adapters.

Antenna design and quality can and normally do make a night and day difference, however they can not compensate for an underpowered radio, but fact is that the EFR32MG21 ITead use is not underpowered.

EFR32MG21 is newer (released later) and on paper the EFR32MG21A020F1024IM32 is more powerful plus have slighly more onboard resouces than the CC2652P, but I think that in practice for average users in a real-world scenario the MCU raw specification of Silicon Labs EFR32MG21 and Texas Instruments CC2652P on a data-sheet comparison will not be as important as antenna quality and antenna positioning.

https://www.silabs.com/wireless/zigbee/efr32mg21-series-2-socs/device.efr32mg21a020f1024im32

https://www.ti.com/document-viewer/CC2652P/datasheet

  • Zigbee Stack = EFR32MG21 support EmberZNet versus CC2652P supporting Z-Stack
  • Both have separate bootloader firmware as standard so can be reflashed without debug adapter.
  • Flash Storage = EFR32MG21 has 1024KB flash versus CC2652P 352KB flash + 256KB ROM
  • RAM = EFR32MG21 feature 96KB RAM versus CC2652P featuring 80KB RAM + 8KB SRAM
  • CPU core = EFR32MG21 80MHz ARM Cortex-M33 versus CC2652P 48-MHz Arm Cortex-M4
  • Both feature 2.4 GHz amplified radio with maximum 20 dBm power transmitter (TX) output
  • Zigbee receive sensitivity (less is better) = EFR32MG21 -104 dBm versus CC2652P -100 dBm
154

I really donā€™t think it will be limiting in the real-world as the chip it uses should offer much better radio performance than other USB adapters, but of course it would be a better product with external antenna.

You should compare it to the popular ConBee II cannot support more then five Zigbee 3.0 child devices.

Again, best practice with any Zigbee mesh network is still to always have a mains operated device acting as a Zigbee router installed in each and every room that has a battery operated Zigbee device.

Make you a deal; I wonā€™t praise it more based on its specs if you promise to not doom it in advance.

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155

OK, I appreciate the additional comments above and think it all makes sense.

Question: this $7 ITEAD Zigbee 3.0 Dongle (with EFR32MG21 MCU), does it has a possibility for soldering a connector to the print board to screw an external (high performance) antenna to it?

156

And if so, do we know of someone already tested this?

157

The only person that I read about who got one in advance is @digiblur but believe he is busy helping kirovilya pre-alpha test the new EZSP implementation for zigbee-herdsman which will add EFR32 / EmberZNet support to Zigbee2MQTT and IoBroker. See [WIP]: EFR32 EmberZNet EZSP adapter by kirovilya Ā· Pull Request #317 Ā· Koenkk/zigbee-herdsman Ā· GitHub ā€¦though I think digiblur mentioned that he plans on testing it and blog about it.

158

I did test it with the Zigbee2mqtt dev branch and ZHA and it works with both. I am doing some range testing and such with this one as well.

PXL_20210317_180514297
PXL_20210317_1805142972688Ɨ1857 1.57 MB

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159

No. I have a picture of it here. https://www.digiblur.com/2021/03/zigbee2mqtt-with-sonoff-zigbee-bridge.html?m=1

160

OK, is the conclusion that no connector for an external antenna can be soldered to the board of this new Zigbee dongle?

161

I am sure with a little work it could be done. But is it worth the time? Nahā€¦ Get a cc2652 series.

162

Of course you can, soldering SMA or IPEX/uFL connector used to be a common practice before such USB sticks models were available. Google CC2531 + antenna hack or antenna mod or modification:

https://www.youtube.com/watch?v=RYlvXglUnGc

https://notenoughtech.com/home-automation/testing-9-external-antennas-with-cc2531-zigbee-coordinator/

https://blog.maxwellfarrior.com/2019-11-23/zigbee2mqtt-3/

https://hackaday.io/project/163505-cc2531-usb-adapter-antenna-mod

If I remember correctly; Mat from NotEnoughTech did some real-world range testing on the Sonoff ZBBridge getting results that he was very impressed by, and it only has this type a basic FPC antenna:

https://www.itead.cc/2-4g-wifi-fpc-antenna-with-ipex-connector.html

Look forward to reading your test result as on paper the EFR32MG21 chip have a more powerful radio,

@digiblur Any chance that you consider doing an antenna modification with the new ITead stick?