Low RSSI Fanstel BC833M vs PCA10100

[qwertynoon]

I build device based on Fanstel module BC833M with pcb antenna.

Communication with this device is very bad. I have test the same code in BC833M and origin Nordic devkit PCA10100 and get a crazy defference.

PCA10100 connected to android in range above 200 meters. But Fanstel BC833M only 20 meters.

WHY?????

They have the same SoC nrf52833 and the same signal +8db

Whats wrong? help me please

[Stian Røed Hafskjold]

Did you follow the reference design for the BCM833M module? If possible can you please post the board layout? Thanks.

If you followed the BCM833M reference design and all other guidelines, I think you will have to direct the question to Fanstel.

[qwertynoon]

I have asked them. They lold they have good communication. But it is a terrible. Up to 25 db difference between fanstel and pca10100. Maybe somthing wrong with UICR bytes? I have erase all chip

[Stian Røed Hafskjold]

The default UICR values are fine, no need to change anything in there. Usually you have to place the antenna outside of the PCB or at least make sure that there is no ground plane underneath.

[qwertynoon]

Antenna connected to ground in fanstel module. F invert antenna. No ground. I have tried even without pcb (wiring only) but it has the same result -60db at 2 meters

[qwertynoon]

But what if I erased this UICR data? Will this be an obstacle to the normal operation of the radio at maximum power?