We are currently undertaking EMC pre-compliance tests with a P1 based product here in Melbourne, Australia.
The Device Under Test first failed at an EMC compliance lab. We have come back to our premises and have been able to reproduce the issue using our (newly purchased) Spectrum Analyser, but not in a Faraday cage (as yet).
The emissions tests are failing when there is NO WiFi Access Point to associate with.
The attached spectrum analyser display shows the issues between Marker 1 and above Marker 2.
- Marker 1 = 2484 MHz (top edge of WiFi 2.4 GHz band)
- Marker 2 = 2502.8 MHz
I note that the P1 was in SAFE mode, ie our application firmware was not running. The spectrum analyser was connected directly to the P1’s external antenna connector.
Has anyone got comment on this, especially Particle engineers? This is a real problem for us.
We will repeat this test with a Photon module and report back shortly.