Sonoff Bridge question

I bought a Sonoff Bridge kit with 433Mhz mag switch and PIR sensor. I am flashing them all with Tasmota when the flash adapter arrives that I ordered from Jon. There are a couple YouTube video’s online showing the process and they all seem to just temp solder a cable onto the bridge pins and remove it after programming. I flipped the LED up and soldered a riser in so I could use the adapter as it was and in doing so, I de-soldered the LED because it was in the way. The question is… Is there any reason you could think of that the LED needs to be in there after everything is up and running? I really didn’t want the glowing light on it anyway so if deleting it isn’t going to be an issue, I am not returning it to the case. I mean, I assume all it is for is a visual indicator that it is on and linked anyway, right? And it is a power drain.

I’ve never personally ran across an issue with removing led’s from various devices to keep them from sticking out like a sore thumb @ night (i even have a modified arduino & a wiznet shield with the LEDs adapted to a removable cable because my wife has epilepsy and the fast flashing when uploading new code bothered her, they both function 100% normal with them removed) I’d say run it!! worst case if it doesn’t work u can always put an IR led (to absorb minimal current) on some leads and make it disappear in the case… (you won’t see the IR but this should be unnecessary tho in your scenario) Let us know if it works!! Looks interesting for budget access control!!

Okay. I didn’t figure that the LED had any part of the function of the board short of just indication of state. I will know when it isn’t working because well, it won’t be working :smiley:

In almost all cases, this will be fine. LEDs don’t normally have any influence over the logic of how a circuit works.

However, there are 2 interesting exceptions that I can think of. They shouldn’t apply in the case of the Sonoff Bridge, but they’re worth keeping in mind for the future.

First, I’ve seen LEDs used to do double-duty as a light sensor. It’s crude, but an LED has almost the same electrical characteristics as a photodiode so you can use them to detect illumination!

Second, and more relevant to ESP8266 circuits, one trick I’ve used a few times is to use an LED and resistor as the pull-up on the GPIO0 strapping pin as shown in the attached schematic. In this case the LED is providing bias to the strapping pin, which keeps the ESP8266 from going into bootloader mode at start-up. In normal operation the LED doesn’t illuminate, but if you press the “PROGRAM” button it will turn on. This provides visual indication that you’ve triggered bootloader mode.

So in that case, the LED is actually part of the logic of the circuit, and removing it could stop the processor from booting normally.

I think you’ll be fine in this case, but there are always oddball exceptions!

1 Like

I have searched far and wide, and elsewhere online but alas, I could not find the answer to the question: do you know of a natural gas (methane, butane, propane etc) 433MHz detector that is compatible with the Sonoff RF Bridge?
I’ve already ordered the RF Bridge, Sonoff-compatible door contacts and smoke-detectors but I’m having trouble finding a gas detector as details about what kind of 433MHz signal it sends out are never explained in the item description.

Many thanks

This one maybe?