nrf21540 output power

[Reginaldo]

Good afternoon everyone, how are you?

I'm using custom hardware, Nrf52833+Nrf21540, already reviewed by and tuned by Nordic. We are going to carry out the tests for product certification, but I am having some difficulties in preparing the test.

I'm using the DTM example, from NCS with the overlays for Nrf52833.
x:\ncs\v2.6.1\nrf\samples\bluetooth\direct_test_mode.

I can change channels, physical layer, package type. However, the transmission power is not what was expected, in this case 20dBm. Below are images of our electrical diagram, overlays, configurations and signal analysis.

It will be an error in measurement or configuration. 

Note: The measurement was made by connecting the cable directly to the antenna output, at the point marked in red on the electrical diagram.

    

Thanks in advance.

[Reginaldo]

Note 2: Using the DTM application, I set the Nrf52833 output to 0dBm.

[JONATHAN LL]

Try to use the Radio test sample in stead, it will let you control both the devices and also works well for testing unmodulated single channel. 

https://github.com/nrfconnect/sdk-nrf/tree/v2.7.0-rc3/samples/peripheral/radio_test 
https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/nrf/samples/peripheral/radio_test/README.html#user-interface 

Note: The measurement was made by connecting the cable directly to the antenna output, at the point marked in red on the electrical diagram.

Also do you know the loss in the cable you are using ?  Should not be that much as you are seeing but for accuracy of the measurement test setup it can be good to know. 

Regards,
Jonathan

[Reginaldo]

Thanks