[600MRG] Radio Noise Data Logger

[Michael Mussler]

Here’s a plot I made of the neighbor’s grow light noise. I recorded the data using an Arduino Uno micro controller and a Data Logger “Shield.” It rectifies and filters the audio output from my Elecraft K3 running with the AGC turned off. The radio was tuned to 3490 kHz, just below the 80m ham band. The Logger Shield has a real-time clock feature that provides date and time stamps for each data entry. It can be set up to record data at any time interval; I’m recording the relative noise level every minute continuously 24 hours per day. The data is saved on a self contained micro SD card, the same cards many digital cameras use to store photos. The .csv files on the memory card can be accessed using a computer and one of the popular spread sheet programs. 

I am sharing this plot in the hopes that it will give others a tool for identifying and tracking down noise sources in their radio environments. You will note a 20 hour on, 4 hour off characteristic with this particular noise source. Googling "20/4 Lighting Cycle" brings up several blogs that discuss this timing characteristic as a popular indoor marijuana cultivation lighting regime.

If you would like the circuit and program details, please contact me off-line. I’m happy to help anyone faced with similar radio noise problems.

73
Mike Mussler, AI8Z, WD2XSH/12