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YateBTS / BladeRF kalibration

« on: December 23, 2017, 01:52:28 PM »

Hi Guys

I'm trying to calibrate my x40 as per the wiki on github

~/kalibrate-bladeRF# kal -s GSM900
Actual filter bandwidth = 1500 kHz
rxvga1 = 20 dB
rxvga2 = 30 dB
kal: Scanning for GSM-900 base stations.
GSM-900:
        chan: 92 (953.4MHz + 11.503kHz) power: 27093.53
        chan: 93 (953.6MHz - 672Hz)     power: 25353.03
        chan: 94 (953.8MHz - 680Hz)     power: 20875.63
        chan: 95 (954.0MHz - 667Hz)     power: 8527.52
        chan: 100 (955.0MHz - 672Hz)    power: 9893.46
        chan: 101 (955.2MHz - 667Hz)    power: 12172.33
        chan: 102 (955.4MHz - 667Hz)    power: 19865.76
        chan: 103 (955.6MHz - 667Hz)    power: 25914.98
        chan: 104 (955.8MHz - 676Hz)    power: 28278.21
        chan: 105 (956.0MHz - 667Hz)    power: 30534.90
        chan: 119 (958.8MHz - 667Hz)    power: 36344.74
        chan: 120 (959.0MHz - 667Hz)    power: 32870.62
        chan: 121 (959.2MHz - 667Hz)    power: 31070.63
        chan: 122 (959.4MHz - 919Hz)    power: 28242.02
        chan: 123 (959.6MHz - 667Hz)    power: 26128.25
        chan: 124 (959.8MHz - 672Hz)    power: 21426.78

....


~/kalibrate-bladeRF# kal -c 93
Actual filter bandwidth = 1500 kHz
rxvga1 = 20 dB
rxvga2 = 30 dB
kal: Calculating clock frequency offset.
Using GSM-900 channel 93 (953.6MHz)


Found lowest offset of 436736.125000Hz at 953.600000MHz (457.986708 ppm) using DAC trim 0xffc0


This seems a little excessive compared to the what the wiki suggests, is this a workable value to set as a trim in the cli ?

(by the way when i do kal -c 103 it hangs and doesnt seem to calibrate - no dots for progress)

Many thanks!

Xarion