DTM without external clock source

[Jake]

I made a board without external 32kHz crystal. So, I changed NRF_CLOCK_LFCLKSRC source to NRF_CLOCK_LF_SRC_RC, which is used in ble_stack_init.

Now, I need to make DTM firmware. Should I change clock source in DTM software? If it is, what is the point to modify? I couldn't find.

[sage]

Hi, The reason why Jake asked this question is due to the spurious emission fail. We are under certification testing but failed. the test item is measuring the spurious emission during RX mode. the specification requests -54dBmW however, my board shows -52.28dBmW@channel 0(2402MHz). the testing was conducted using DTM firmware with nRFgo studio application. we set the TX power @ 4dBm

Could you please give us any tip on this?

[FormerMember]

Okay, I see. Are you testing against the Korean teleregulatory requirements? Which chip do you use, nRF51 or nRF52?

I could be very useful to see your schematic and layout (altium or gerber files). Could you upload it here (if it is okay to make it public) or create a new support case from www.nordicsemi.com and refer to this thread?

Note: For testing the radio it is easier to use the radio test example in the SDK.

[sage]

Yes, it is a requirement from KC program. we'll open a ticket in the support site rather than open our design file.

[sage]

we are using nRF51822 extended temp version

[sage]

I have just submitted a support case with the hardware design files. please take a look at it and let me have your opinion as soon as possible. Thanks alot