Introduction: LOG WiFi Analyzer

About: Lazy Old Geek

I found this partially started project from several years ago. I’m not sure why I never submitted this but will attempt to do so now.

So the other year this Lazy Old Geek (L.O.G.) found this Instructable:

I think the author did a great job so I decided to make my own.

He used a NodeMCU ESP8266. I didn’t have one but I think they’re based on the ESP-12. Well the ESP-07 is very similar to the ESP-12 so I ordered a couple of them. I also bought some 2mm male headers and some female headers so I installed male headers onto the ESP-07 and took female header pins and puts some wires on them so they would fit in a breadboard.(see picture)

Step 1: Hardware:

Instead of an Nodemcu, I used an ESP-07.

My display is a 2.8” ILI9341 display probably purchased on ebay. This is slightly bigger than the one in the original.

Step 2: Printed Circuit Board

Okay, I designed a PCB with a 3.3V supply, 2.2mm header pins for ESP-07 and a connector for the display.

Attached are the Eagle Cadsoft files I used to make the PCB and the schematic.

WARNING: The schematic in the picture does not agree with the Eagle files. I lost the Eagle files using the AMS1117 3.3V regulator shown in this picture.

The attached Eagle files are using a 1N5817 diode to drop the 5v to 4.4(?)v for the ESP-07. For my setup, it seems to work okay but I know it is out of spec. I do not recommend using a diode (and am not sure why I did it).

If you happened to want to use these Eagle files, then you're probably able to make changes. Please change the schematic and board to use a 3.3v regulator.

This PCB also requires a USB-Serial adapter with RTS and DTR as explained in this Instructable:

Step 3: Arduino Sketch

These are the libraries I used for the 2.8” display:

Libraries: Download zip files:

Start Arduino:

Click on <Sketch><Include Library><Add .Zip Library...>

Find the above zip files, open and download

I am currently using Arduino version1.8.12.

The easiest way for me to install the ESP8266 is using Board Manager using this method:

When I did some testing with the ESP-07 I I select “Generic ESP8266 module”.

However, this did not work for this Sketch, so for Boards, under the heading ESP8266(2.6.3), select NodeMCU 0.9(ESP-12 Module or NodeMCU 1.0 (ESP-12 Module)

The Board setting defaults seem to work fine.

Yes, I know that this is not an ESP-12 but I guess they’re close enough so that it works.

I think I rewrote the original WiFiAnalyzer code but don’t know what I changed. It might be for my display or differences between ESP-07 and NodeMCU. In any case, it does work but the credit goes to the originator.

My code is the attached: MTSWiFi.ino.

Step 4: Some Remembrances + Conclusion

I noticed something about the ESP-07 on this board. The ceramic antenna is removed and there’s a cable attached to the external antenna. The ceramic antenna is removed so that there is no signal mismatch if two antennas are connected at the same time.That jogged some memories. My plan was to put a directional antenna on it so that I could see where each signal was coming from.

I had it connected to a directional patch antenna, see next pictures.

I think I may have had the antenna mounted on a tripod.

I can’t remember the results. I suspect they were basically insignificant so I may have just dropped the idea.

So I learned something today. I took a sample from my LOG Wifi Analyzer(see attached) and another from my Smartphone WiFi Analyzer (see attached)

The significant difference is NVR9ca3a93 on Channel 14.

After sleeping on this, I had a Eureka moment, did some research:

As the table indicates, North America does not allow channels 12-14. So that explains why my Smartphone does not show it and obviously the LOG WiFi analyzer does.

What it doesn’t explain is what is the WiFi device with SSID of NVR9ca3a93?

Well, I’m going to make an assumption that this is the the ESP-07 SSID in my LOG WiFi Analyzer.

TIP: One thing I do know is that the ESP-03s that I have have an AI_Thinker SSID. As shown in the pictures, this is the one in my IP-Clock. So I'm guessing that the ESP-07s have an NVR?? SSID.

Conclusion: Despite all the unknowns and doubts this WiFi Analyzer works.

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