How to fix the error: Tx Calibration: MCU error 4 (SXT tune failed)

Projects Lime Suite
41

Hi @BlackF,

Thanks for update.

1 Like
42

hello ,my limeSDRmini HW v1.2 many years ago it stopped working (unsuccessful calibration). Now LimeSuite version: 20.07.2-gf2d96ff0 and LimeSuite version: 23.11.0+dfsg-2build2

[ RF Loopback Test ]
->Configure LMS
->Run Tests (TX_2 -> LNA_W):
  CH0 (SXR=1000.0MHz, SXT=1005.0MHz): Result:(-69.1 dBFS, -7.68 MHz) - FAILED
->Run Tests (TX_1 -> LNA_H):
  CH0 (SXR=2100.0MHz, SXT=2105.0MHz): Result:(-71.4 dBFS, -7.68 MHz) - FAILED
->RF Loopback Test FAILED

=> Board tests FAILED <=

Any ideas? Is this a hardware issue?

43

I tried gqrx to look at neighboring FM transmitters, but there was silence at waterfall. Therefore, I dare to assume that one SKY13411-374LF is not working correctly.

Should I check if RFSW TX/RX signals are coming to RF SWITCH or just replace chips? If there are no signals, the problem may be software related.

Screenshot from 2025-03-16 16-51-39
Screenshot from 2025-03-16 16-51-391128×776 116 KB

44

I blew off the commutator microcircuit with a hair dryer. And connected the antenna directly to both transformers - the result is negative. The receiver is silent.
I make a suggestion - the problem is related to the software. I have already tried all available firmwares, I will try again (Altera USB blaster it is ready)))).