thank you for the reply. i changed it to 3nh. but still not detecting. I programmed the firmware again with no issues. but no bluetooth is seen even at very closer distance. my pcb is 1.6mm thick, would that cause such a problem. i'm sorry for my silly questions, im not an electronics engineer.
do i need to change the pcb or am i missing something? Is there any other procedure to be done after programming the cc2540.?
these are the crystals im using
https://www.digikey.in/en/products/detail/abracon-llc/ASFL1-12-288MHZ-EC-T/687856
https://robu.in/product/ysx321sl-32...d-smt-metal-surface-quartz-crystal-pack-of-2/
Thanks IVX I finally got it working. I had few more PCBs, soldered same components to another , and it worked!!!
I hooked up input and output to an audio interface and measured response.
with PEQ OFF and with only cross over it looks fine. HP 20Hz 12db/oct and LP 80Hz24db/oct.
but when I just turned on PEQ with no filter inside the xover range. settings on phone looks like:
but the response is
it seems to be adding a 10Db boost at 45Hz. while its not given in the xover settings.
then I added a PEQ 55Hz Q10 -2Db and it looks like this :
on Phone:
But the response from the device:
we can see that 55Hz PEQ there , but that huge boost at 45Hz is still there. what is going on.. what am i missing. Im using android phone.
