I have recently purchased a DSO138 from Banggood and based on viewtopic.php?f=18&t=511
(no tear drops) it is a fake. Interesting- it has the updated firm ware. At least the reported number is ...-50.
It worked for a few days, now I am trouble shooting no trace on the 3.3V 1k Hz test signal and abnormal -10.69 vs target -8.08 at
TP25. The voltage at L1 is also -10.69 instead of the target of -8.11V. Rest of test points are close to target with 9.36V input. Any suggestions?