Sonoff RF Bridge extended range

Theengs OpenMQTTGateway Radio frequencies gateways 315mhz, 433mhz, 868mhz
1

Hi,
I have a sonoff rf bridge and i need to replace the receive antenna cause i have rf module that the bridge didn’t get the code .
any idea ?

2

Hi,

How far is it from the bridge?

3

10 meter i think… the problem module is like 20 meter from bridge and the bridge is in my warehouse

4

Could you indicate what brand/model of module we are talking about ?

5

https://www.aliexpress.com/item/33000556137.html?spm=a2g0s.9042311.0.0.281d4c4d9Gahtd
this product.

6

oh, unfortunately this is one of the more powerfull that I know.

The different possibilities are:

  • add another rf bridge in your wifi coverage but closer to the sensor
  • move your existing rf bridge, but I think you already think about it
  • Modify the RF bridge receiver antenna
  • Modifiy the sensor emitter antenna
  • FInd a more powerfull door sensor (I haven’t done some db test with my range yet)
7

this is what i am looking for… can you help me with that ??

8

OK i have been modified the antenna its now recognize over 50m…
i just remove the left antenna(near the buzzer) and take network wire(1 from the 8 wire) and soldering it to board and its now much longer. the wire is about 60-70 cm long.

1 Like
9

Great!

You were lucky if you get better performance without having done some math. Indeed the antenna length should be calculated following the wavelength of the frequency.
But if it works I will let it like that :slight_smile:

10

Well the happy was too early.
I managed to improve the absorption slightly but probably not enough because I can’t absorb the module that is farther away.
I’d love to get you the antenna size calculation formula.

11

Theoreticaly 17.3cm
here is some reading:
https://www.meteocercal.info/forum/Thread-Looking-for-best-Antenna-model-your-opinion-on-exotic-designs

1 Like
12

@1technophile I tried to mess with the antenna but unsuccessfully, there is probably an antenna power limit.
Anyway I ordered another board called GT-38, but unfortunately I can’t operate it.
Is there any chance you have experience with this board?

13

Unfortunately no :frowning:

15

Sorry to comment on an old post but I’m still stuck with it.
I bought another RF bridge I put it in a box with another WIFI module and less than 4 meters away it receives the signal from the RF sensor.
I’m already crazy about it … I bought a SRX882 433Mhz module and it’s not that long term either, is there a way to make good reception for RF products?
I was told that there might be a problem in the sensor that has a really short antenna, it has an LED. Will I turn off the LED that will give more power to the transmission?

Apologies again for all questions but I can’t finish this project !!!

16

I don’t think so.

Do you power it with 5V?

17

Sure with 5v… but now its look like the moudle didnt work… does he need the CS pin connect to 5v also ?

18

That’s what I used as a source of information, take a look.

19

Just FYI, for my previous automation hardware ( X10/CM15 receiver, which was also 433Mhz) I had build a ground plane antenna and added a generic VHF/UHF/FM 20db signal amplifier. It was working perfectly and added subtantial range (200+ft).

http://www.shed.bz/tutor/CM15mods/CM15mods.html

The antenna is still in the attic.
I now have a full Sonoff/Tasmota system and I’ve ordered an extra Sonoff bridge to test it out;
just need to add a connector for the coax cable and bypass the stock antenna.
will report back if it works out.

If someone tries it meanwhile, let me know the results.

Hope this helps,

20

Thanks for sharing. Please update us when you test your new hardware as limited range is one of the very important issues with basic RF components and every chance of improving it is a huge benefit.

21

For sure Will do, thx