handheld oscilloscopes bandwidth tested. hanmatek ho52 and "tablet osciloscope"
I build it probably 10 years ago, um based on adcmp 580, cheap, its basically a very fast comparator. It can generate it basically can get a pulse in and the pulse out is 37. picoseconds typical typical rise time, so its good for measuring Bandit of an oscilloscope. So we, the formula for measuring the bandwidth on oscilloscope, would be something like 0.35 or 40 for modern oscilloscope, and you divide that by the rise time you can get the rise time in. If you get the rest time in microseconds, then the bandwidth uh will be in megahertz, so um. Basically I have this uh. We will start with this tablet oscilloscope. So it has a nice touch, interface um. They claim uh. It has 100 megahertz and one giga samples per second um. I wasnt able to get that so uh, first of all, um it doesnt always so, if I increase the the time base to 10 nanosecond per division, it doesnt always trigger so its already having so 15 nanoseconds uh per division. It triggers well, but at 50 10 nanoseconds it doesnt trigger well Im gon na try to catch one of the, so one of the pulses again this is this – is I played of this. This is not super normal, maybe Im doing something wrong. Uh anyways lets see if I can catch one of the pulses playing. Maybe we can play or trigger here not getting the pulse so um anyways, you can see quickly here maybe um.
So this is this is at 15 nanoseconds per Division. I was able to previously catch up Pulse, so lets play a coupling here. Lets go to a c coupling. I have a 50 ohm Terminator here its doing something very weird that this so it definitely doesnt function very reliable at this frequencies, so anyways uh. If we try to do the rice time, lets try it here, then we get around 15 nanoseconds uh lets say at 10 nanoseconds lets round it 15 nanoseconds um. So this Bandit, if you divide 0 with 35 by 15 nanoseconds thats, going to give you between 20 and 30 megahertz so no way this is delivering 100 megahertz, so um yeah um. Is this oscilloscope good, um yeah? Maybe if you dont mind um not getting the entire frequency, it doesnt really work well at that high frequencies. So lets look at another one because they are not not well bad, so this is uh hanmatec, h, 052 Ill try to connect it one hand okay. So this is pause now lets try auto set see what it does. Okay, so we got. We got the pulse Im gon na try. We got the pulse its one kilohertz going coming from my signal generator. I also have the input signal on this oscilloscope. So this goes into the signal: generator uh and the basically theres a comparator here and a very high rise pulse, which is in like a problem when what a couple of water magnitudes higher than what? What were trying to measure uh goes into this oscilloscope.
And I have a 50 ohm Terminator because Im not sure if its um oscilloscope can terminate by on their own um so anyway, lets see. Lets see the rise time here were gon na go to horizontal menu. Uh were gon na raise a time base. Actually is the other way around so were gon na start seeing okay, so the limit reached Im gon na pause, it um Im gon na, go to my cursor measure, cursor okay, so we get 3.6 nanoseconds, so 0.35 divided by zero. Three point: six nanoseconds! It gives us around the 100 megahertz bandwidth on on a single Channel um. Now, if I enable the another Channel trying doing that, okay lets run Okay, so you see were getting half a bandit. So in conclusion, uh yeah uh this oscilloscope with chip oscilloscope, I hit the miss uh, make sure you you measure the bandits one you get you can build. Such fast pulse generate in a simpler way or you can get some other generator. Anyways hope hope this helps.