SDRGREEK STORE is not on the approved WiKi list of dealers it may be possible that you may, have a knock-off or clone.
Which selftest failed? Did you preform the signal level setup? Did you connect port 1 and 2 correctly? Did you turn on the calibration signal to 30khz?
You need to give more info than just the selftest failed.
Clyde KC7BJE
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