Sonoff RF Bridge extended range

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.

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

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@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?

Unfortunately no :frowning:

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 !!!

I don’t think so.

Do you power it with 5V?

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

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

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,

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.

For sure Will do, thx

For anyone interested, here’s my feedback:
I modified the Sonoff bridge and reinstalled my quarter wave ground plane antenna (see above - located in the attic as my house has aluminium siding, much better reception);
I am now getting anywhere between 100 to 150 feet reception range; signal is loud and clear from all sensors, indoors and outdoors. Modified both my units (Tasmota/Portisch and OMG/Pilight)
Here are a few pictures of the Sonoff mod; have a close look at the hole placement as it could interfere with other components + small tape to avoid contact between receiver antenna and connector.
Use the nut to find hole placement (first 2 pictures), small hole first then drill 3/8.
You can probably use other/simpler antennas like the good old universal telescopic TV antenna but will surely have to fine tune and range will shorten.

Feel free to provide feedback on your own experiences/results.

Cheers.

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That’s interesting. So you connected your external antenna parallel to the internal one, is that correct?

Correct.
I built the ground plane antenna for 433mhz (vs 310mhz for North American X10) and the results are similar: couldn’t get good reception (especially outdoors - bridge located inside the house) and now I get around 150ft (no line of sight). Really worth it if you have sensors far from the bridge and/or outdoors.

Thanks for confirming. I take you used 433Mhz in your calculations?

Correct. If you don’t want to invest time in the custom antenna, I guess you could also test with a telescopic antenna first to see the improvment in range and go from there; One thing is for sure, the connector is really useful.

so where or what you connect to rfbridge ? can you upload image off the external ANT ?

Like this. See links above for DIY details.

Hi!

Occasionally I had problems controlling the roller shutters in the distant corners of my house, so I tried to add an external “WiFi router style” rod antenna to my RF Bridge (Tasmota+Portisch) the same way, but connecting it to the TRANSMIT module. It was described as specific for 433MHz RF, and it is 17 cm long, so I was hopeful.
Practically it did not help, the range dropped to the half of the original and I even could not restore the it after removing it or reverse the modification.
Checked and measured whatever came to my mind, but no success. Any idea what could I destroy?

On the other hand, in your picture you have connected the negative pole of the connector to the ANT point of the RECEIVE module on PCB, and the positive pole to end of the internal antenna, which is not even connected to the ground (or anything on the PCB, it only holds the coil in place).
Based on my (limited) knowledge I would connect the positive to the ANT and the negative to the GND. What was your idea?

I’m completely new to RF technology, so any advice would be highly welcomed!
Thanks!

I can’t comment on the transmission power and/or potential hack as I use the device solely to receive signal.
However, I can confirm that the above mentioned mod+ground plane antenna added significant reach (from 30ft indoors only to 250ft indoors/outdoors).
Would have to check regarding ground location but since the results are there not sure I’ll bother…

Hopefully someone can jump in to assist you regarding RF transmission power.
Cheers,