hackrf

The Hackrf only works reliable at higher sampling rates. However the raspberry pi can handle higher speeds but can not execute all SDR transformations. Also the Hackrf is a halfduplex device, you have to switch sdrberry to halfduplex data transfer. That is tx and rx data cannot be exchanged at the same time.

The config below configures the sdrberry to use halfduplex and with a samplerate of 8Mhz which is decimated to 0.5 Mhz The decimation configuration is:

0 = 1
1 = 2
2 = 4
3 = 8
4 = 16
5 = 32

[hackrf]
audiobuffersize = "4096"
bandwidth = "1750000"
dc = "0"
decimate = "4"
gain = "50"
halfduplex = "1"
if-gain = 21
samplerate = "8000"
samplerate_tx = "8000"
span = 192

I have tested this on a pi5, for pi4 maybe a higher decimation factor is better.