LCD Handheld Digital Oscilloscope Kit - 2 Channel 2.8'TFT Mini Automotive Oscilloscope Bandwidth 120Mhz Digital Oscilloscopes Portable 500MS/s Sampling Rate, Vertical Sensitivity 10mV/div~10V/div

This hand held oscope has performed well so far. I used it once to setup lissajous signals and it did not disappoint. The battery held up well while adjusting signals for a few hous. The menu is easy to navigate

Hand-held Zeeweii ScopeWhat I like:VersatileMostly relatively easy and intuitive to useOn-screen display of trigger level and triggering position on waveformDigital measurements of signal (voltage, frequency etc)Different colors for the two channelsGood accuracy - time base agrees with my analog lab scope, generally within a percent and good agreement of vertical scales.Has XY modeBuilt-in function generatorBattery life appears to be goodNice carrying packWhat’s not so great:Relatively low resolution display, although good enough for most purposesInstruction manual lacks comprehensive information and specificationsFlimsy case protectorThis is my first experience with a device like this. For most test equipment, I prefer analog devices to digital ones, and If I had to choose, I would not give up my 4 channel 100 MHz lab oscilloscope, which has served me well for many years. However, for an instrument that’s very portable and can be used to make quick measurements in the field, this Zeeweii unit seems to be quite serviceable. It appears to have some ability to examine portions of waveforms in detail, although these are not as sophisticated as the B intensified and B delayed functions in my lab scope. I made some relatively crude measurements of frequency response, using my 100 MHz lab scope as a reference. Up to about 80 MHz, both scopes agree. Above that, the response of the Zeewai unit seems to have a slight peak, through 115 MHz, but by 120 MHz its response has dropped to zero. I think it’s fair to say that the unit can be relied on quantitatively through 80 MHz and is qualitatively useful to about 110 MHz or so for sinusoids or waveforms having relatively narrow bandwidths.It has a video output which is just barely mentioned in the manual. It appears to be a 625 line raster with a 25 Hz frame rate, most likely PAL. The scope did a good job of measuring the frequency of the color burst at 4.44 MHz, which is very close to the actual PAL frequency of 4.433 MHz. I plugged it into the composite video jack on a small HDTV and, somewhat to my surprise, the TV recognized it and produced a color image of ZEEWEII.Best resolution when using the FFT function occurs when as many cycles (or as long a time span, for aperiodic signals) as practical are displayed. My first impression is that, of the various choices, the linear option on the FFT menu is the best. The resulting FFT plot is difficult to see through the display of the input signal, and no units are provided along the x axis, which should be frequency. This is just based on a relatively short period of time playing with the function, and possibly I will learn additional things about it with time. At this point, though, it doesn’t seem to very useful.The function generator can be set to give any of a number of waveforms including sine, square, triangle and sawtooth waveforms, as well as what appears to be (sin x)/x, a random output and half- and full-wave rectified sine waves. The sine wave works up to 10 MHz, with other waveforms up to 2 MHz. The square and sawtooth waveforms in particular show some ringing at higher frequencies. Just for fun, I measured the harmonic distortion of a 1 kHz sine wave to be about 2.5%, mostly second harmonic, so you probably don’t want to use it as a source for evaluating audio equipment. The 2.5% figure seems to hold constant at frequencies between 20 Hz and 20 kHz. All of these signals have a DC offset, which in the case of the sine wave is 1.25 volts, and a peak to peak voltage of 2.5 volts.After 7 hours of operation, mostly with both channels in use and the signal generator on, the battery charge, as indicated by the icon, had dropped to about 20%.I haven’t had it long enough to be able to say anything meaningful about its reliability. Based on the assumption that reliability will not be a problem, I’m giving it four stars instead of five, mainly because a higher resolution display would be an improvement and a good manual would be helpful. I’ll be keeping it.08/26/2023

Starting out years ago nothing like this existed for 100$. I have a tektronix rm561a beast that was used by NASA to develop the Saturn v, it works but analog vacuum tubes are hard to come by. Then I have a 20mhz bench top machine. I wanted something I could save wave forms with and portable as I needed to troubleshoot something at work. This works so well I'm thinking I should get rid of my 20mhz bench unit. The power in this handheld unit is insane YouTube has a hour long video talking about button combinations and features. Yet simple enough to pull out adjust the time base, and v/div without a manual

I'm really impressed with this little portable Oscilloscope from the MakerHawk store on Amazon. It's a small but highly capable 2-trace scope with a built-in signal generator. The kit comes with the scope itself, TWO 1X & 10X probes with an adjustment screwdriver and spare colored identifier rings (to make it clear which probe is attached to which input while working with them), a pair of cables for connecting to the signal generator output (plugs to the generator on one end, and alligator clips on the other end), a cable to allow output of the oscilloscope display to a composite video input of a monitor or TV so equipped, a USB cable to charge the scope from any USB power source, and a pretty well-written instruction manual that adequately describes all the functions of this tool. All these are packaged in a high-quality zippered semi-hard case for safe carrying and storage.I used to have an old (practically antique) old oscilloscope several years ago that took up a lot of room, was really heavy to carry around if needed, made a lot of noise while operating (from loud cooling fans), and because it was so old only ONE of the two channels worked properly. I finally ended up selling it to a vintage electronics equipment collector, but a few times since then I've had opportunity to regret that decision when it would have been helpful to look at a waveform in electronic equipment I was trying to repair. But now with this model I don't have to regret getting rid of the old one any longer. And this new model is FAR more capable than the old one (having some capabilities that I haven't ever heard of, quite frankly), with a greater bandwidth, FAR superior portability, the aforementioned frequency generator, and waveform storage capabilities (and the capability to download the waveform bmp files to a PC through USB). I also love that the display show not only the waveform, but also the amplitude (at different measuring points) and frequency of the waves!The waveform generator provides sine, triangle, sawtooth, square, and what I will call a random modulating waveform for lack of a better term. A few of the pictures I included with this review show some of these waveforms. All the available waveforms allow setting the frequency and some of them also support changing the duty cycles of the waves.My old scope had several knobs for making the necessary adjustments to be able to effectively monitor the waveforms in a circuit, so I was used to just turning knobs until a steady display was on the CRT. This new one doesn't have any dials, but it has buttons that do most of the same things, as well as menus of settings to control everything else. The controls are actually very well implemented once you know where everything is. I like how the LCD display shows the two different traces in different colors to facilitate keeping track of which waveform is which.As I said, I'm thoroughly impressed by this little scope, particularly at what I consider to be the low cost. It's a well-built, compact, and capable unit. I'm so glad that I now have it at hand when I need it!