Japan Qualification of nRF52832 Product

[EddieR]

Hi all,


I am trying to certify a device with an nRF52832. No issues with US and EU, but for Japan we need to have a constant transmission on channel 17 (2440 Mhz). I attempted to use the "Radio Test" example (modulated and unmodulated TX) and the "Direct Test Mode" app from SDK 17.1.0. Both apps produced transmissions that our test house called "too wide". We tried both our custom device and a development kit, but both produced the same result. Below is an image of readings from two devices, one with with advertisement channels transmitting and another with channel 17 transmitting. Our goal is to have the transmission on channel 17 be a similar width to the advertisements. Is there something I am configuring wrong, or using the wrong test application? Any help would be appreciated.

Thank You!

[Simonr]

Hi

We recommend using an unmodulated carrier from the radio test sample project. The result should indeed not look as wide as what you're seeing, so our guess is that the radio test or spectrum analyzer isn't configured correctly.

Best regards,

Simon

[EddieR]

Hello,

Thanks for your reply. I tried the Radio Test project, but even in the nRF Connect RSSI Viewer app the transmission is leaking into channel 18. Below are my Radio Test configurations and what I'm seeing from the RSSI Viewer. Is that what I should expect to see in the RSSI Viewer?

Thank You,

Eddie

[Simonr]

Hi

This is done using a custom nRF52832 board, correct? Have you done any antenna tuning on your end, or are you able to recreate this behavior on an nRF52 DK for example? My guess would be that your board isn't tuned correctly, but it could still be that the test process isn't set up correctly.

Best regards,

Simon

[EddieR]

Hello,

We have tested with both our custom board and a few nRF52 DKs. All produce the same result. Below is a test with two DKs, one constantly advertising (this DK is a littler further away) and the other using a hex provided by Nordic to transmit on Channel 17. We also tried swapping DKs (and our custom board) and it produced the same results.

Below are the settings on our spectrum analyzer:

I have also attached the hex file that was used.

Mod-radio_test_4_Ed.hex

Thank You,

Eddie

[EddieR]

Simon,

The spectrum analyzer was incorrectly configured and now looks correct. Thank you for your assistance.

Sorry about all this,

Eddie