Welcome • User Guide
ToS • Privacy • Canary
Donate • Bugs • License

©2026 Poal.co

423

So I picked myself up a shiny new Arduino WiFi Rev2 and updated the firmware to the latest 1.2.8.

Trying out some simple sketches. I'd like to set the hostname for my sketch so I use the example:

WiFi.setHostname(“MyArduino”); // attempt to connect to Wifi network: while (status != WL_CONNECTED) { Serial.print("Attempting to connect to SSID: "); Serial.println(ssid); // Connect to WPA/WPA2 network. Change this line if using open or WEP network: status = WiFi.begin(ssid, pass); // wait 10 seconds for connection: delay(10000); }

Of course, the hostname as reported by the router never changes, it's aways "arduino-abcd" with the abcd being the MAC. That's not a deal breaker, but it looks like Arduino has had some problems with this for a while. Anyone use these and get this to work?

edit: Don't suggest I use ESP stuff instead. Those have serious issues with RF noise, and they're not good for my applications.

So I picked myself up a shiny new Arduino WiFi Rev2 and updated the firmware to the latest 1.2.8. Trying out some simple sketches. I'd like to set the hostname for my sketch so I use the example: ` WiFi.setHostname(“MyArduino”); // attempt to connect to Wifi network: while (status != WL_CONNECTED) { Serial.print("Attempting to connect to SSID: "); Serial.println(ssid); // Connect to WPA/WPA2 network. Change this line if using open or WEP network: status = WiFi.begin(ssid, pass); // wait 10 seconds for connection: delay(10000); } ` Of course, the hostname as reported by the router never changes, it's aways "arduino-abcd" with the abcd being the MAC. That's not a deal breaker, but it looks like Arduino has had some problems with this for a while. Anyone use these and get this to work? edit: Don't suggest I use ESP stuff instead. Those have serious issues with RF noise, and they're not good for my applications.

(post is archived)

You are currently inside a comment thread.
Click here to see all the comments (12).
[–] • 1 pt

you must use the models with the metal shielding over the uC.

That does absolutely nothing. I've tried multiple models with a shield, including 07, 12, and ESP32 in the castellated package. They leak EVERYWHERE, including the antenna. I can take a relatively deaf SDR stick, put it in the next room 30 feet away, and still see the 318MHz peak from an ESP32 with a metal shield. My garage door opener is even more sensitive, it can see the emissions from anywhere on my small patch of ground. FCC certification for an intentional radiator in this case is meaningless, it just means that it does what they say it does.

I suspect the emissions from the device itself were interfering with the device I was banging, but I don't have any way to prove it. The project was abandoned and the stuff went in the resale bin.

[–] • 1 pt

It's worth point out, not all of the modules are the same. ESPs are FCC certified in specific uses and the shielding is the requirement which allowed them to do so. I do know some are more noisy than others. I can't speak to any specifics of what you're seeing.

You have a spectrum analyzer?

[–] • 1 pt

I had access to one at the time. My initial problems started showing up here in my home lab, when certain devices operating at 3x0MHz started to malfunction. This included a consumer garage door opener manufactured by a company that primarily does commercial devices (320MHz) and an old X10 RF control system (310MHz.) I tracked it down by scanning the band with a cheap SDR radio and finding a wideband noise source at ~318MHz. This was tracked to the ESP12 devices I had on the bench running life tests, and I confirmed it with my then employer's RF lab, which gave me access to several HP spectrum analyzers. Didn't even need a probe for this, a piece of cable free air was enough to give a peak on the analyzer.

It didn't matter which module I chose, 8266 or 32, shielded or not. They all emit 318MHz. The modules are shielded on one side only, so you get leakage out the back, out the holes for the antenna, off the connections, and off the antenna itself. For all intents and purposes, there is no shielding on these. I can hold an ESP32 within a few feet of my garage door opener and watch the receive lamp come on and stay lit. (it's looking at raw input signal, doesn't care if there's modulation on it.)

The FCC certification falls under part 15C, and covers the WiFi band emissions only. Looking at the test report for 2ANHN-ESP8266, there is a spur at 319.9MHz. Since my SDR radio wasn't very accurate, this is probably closer to what it actually is, and they're seeing it with one module. My test was with 10+, and it was enough to saturate the area with enough noise to knock both the above-mentioned devices off the air. There are multiple other spurs, but since they aren't on restricted frequencies no one cares - they're noted and that's it. But...the module they used is some oddball design, so chances are none of the currently available devices have any certification beyond the ESP chip itself. That there's no ID printed on the shield of the modules with such seems to support that.

So there's nothing I can do. The ESP chipset is great if you don't have any other devices in the general radio spectrum, but as there are commercial devices operating there, they're useless for some applications.