Custom Board - Wire Antenna

[User1321]

I have made a custom PCB with the nRF52832, following the circuit reference, I used the C3 and L1 for tunning the antenna. Instead of a chip antenna I placed a wire in the track to create an antenna and evaluate performance, but when I flash the BLE example son my board nothing happens, no advertising is done. I have changed the antenna length but, while scanning from my phone I don't see my board advertising.

Currently, I don't have the Vector Network Analyzer to evaluate the impedance matching, instead, what I have done is to change the antenna length but nothing.

Does anyone have any idea what could be happening? In theory, since it is a wire antenna I should be able to see at least any advertising, right?

[run_ar]

I would expect you to see something even if the antenna is mismatched. Could you check with a debugger if you initialize the Softdevice correctly and are able to start advertising?

[User1321]

Yes,Softdevice is being initialized properly, in fact, once tthat he program is started, it conitinues running (forced led blinking) without any restart. 

I am starting to think that it is related with the crystal oscillator of 32768Hz oscilator.

BLE cannot work without it, rigt? How can I check if the crystal is not working properly? 

[User1321]

It might be also that the 32MHz crytal is not placed properly, if that is the case, how is it that all the peripherals are working properly, before I was just testing the uC without the BLE capabilities, now that I am facing the problems, I think it might be something related with the crystals, is it possible that all peripherals (including timers) work fine eventhough the 32MHz crystal is places wrongly? Is there anyway to test this?

[run_ar]

You could try changing to the 32kHz RC oscillator. remember to use the 500 ppm setting. If that works, and the 32 kHz crystal does not, you can take a closer look at this crystal.

[run_ar]

Are you using any peripherals that require the hfxo? or could you have been running on the internal rc?

In general you should check the datasheet of the crystal oscillator and make sure you are using the correct size load capacitors. You could also upload your schematic and layout if you want us to take a look at it.