Disturbance from 230V with my RF receiver module

Hi!

I have an Arduino Uno with 230V Relay Modules, a simple 433MHz RF Receiver ($1 eBay) and a roller curtain/shade running on 230V.

On the test bench, without using 230V shades, it works perfect. But as soon as I connect my shades, the RF messages are often lost - resulting in unsmooth up/down.

I haven't done any measuring, but I guess the 230V has some noise going throw the relay module (through signal cables or gnd) back to the Arduino.

How can I solve this? Any suggestions? Filters?

When building my project box, I was concerned with the EMI produced from power switching, so I isolated the best I can by having all my DC circuits in one area, and the AC in another area, and only the relay module itself has been located in the AC section. I have my Mega and breadboard mounted to a piece of plexi that has been taped off on one side with aluminum ducting tape. In my studies, it was suggested somewhere to put my Arduino into a faraday cage, but for my project, this was not practical so I tried the tape method and it seems to be keeping the EMI isolated, but then again, I'm not using any wireless devices and my voltage is only 125 VAC.



The receiver aerial. Is it near your 230volt wiring/relays?
You could try moving the RF receiver away from the 230v wiring, or use a "sleeve" aerial, made from a few meters of thin coax.
I could post a "recipe".
Leo..