Oscilloscope Signal Generator with 2.4" LCD Display 154 PRO Digital Oscilloscope Portable 500Khz 40Ms/s Sampling Rate 18MHz Bandwidth Built-in 1000mah Battery Handheld Oscilloscopes with X1/X10 Probe

I bought this to adjust my subwoofer amp gains. Worked great. No distortion.

The unit has a very nice display, the scope function works well, the component function works well, and the function generator seems to operate flawlessly. The only negative point that I see on this instrument is that the voltage tester is not polarity insensitive. You can damage your instrument if you do not connect the positive and negative terminals up correctly on the voltage input connector. I wish the manufacturer would address this issue.

Great meter for the money.

Bought it 4 times

I had great hopes for this device based on the previous reviews. I charged the unit before testing it. The three connectors will not fit any of your other test cables, but a BNC adapter and clip leads were supplied. I connected the oscilloscope to the signal generator and set it to a 1kHz sinewave. The oscilloscope showed a square wave. The changed the generator frequency to 20kHz. The scope image didn't change. Triangle wave also showed as a square wave. I then tested a NPN transistor and got reasonable results (not verified). I then tested a N-Channel MOSFET transistor and got reasonable results. I turned the unit off. Upon showing the MOSFET test to a friend, the device indicated the MOSFET was now a Zener diode. Nothing would change that. With no device connected it still indicated as Zener diode. I never connected it to any outside device, but the poor instructions hinted that you could break it by apply a negative input. It got returned the very next day without difficulty.

Good tool using for car audio, cheap is fine i only needed it for a few short uses and it did the job.

everything was there and works as it should

I really wanted this to work for me but the accuracy on this device is bad. Playing any test tone hz the device would read anywhere from 5 to 10hz off. That is bad since the whole point of a osciliscope is to measure a constant frequency to determine its wave form peaks. If that waveform keeps jumping around then its impossible to make sure your circuit or equipment settings are accurate.Device also freezes up and locks display when voltage changes too much from the reading your trying to read. Like if your at 1v read mode and your input voltage changes to 5 volt the screen freezes up and you have to hit the clear button but that resets everything and you gotta pain stakingly navigate the menu with the tiny buttons again to get back to the settings you want.Not for people who wants to really troubleshoot and measure stuff accurately. This is more of a toy for kids to learn about electronics.Returning item.