Get nearly 200MHz without any modifications!
All tests are made with unmodified Hantek DSO5102B.
I make short test becouse many peoples do not use direct cable with termination to scope from DUT.
Most of times peoples use probes of course. So, what is important: scope BW alone or probe+scope BW?
(of course both are important but in practice normal use is with probes.)
Now I make only one "big trick". I did not use probe GND wire. I use normal universal probe adapter to connect center and GND just on the probe tip. (It is BNC and it have hole for probe and it connect GND and tip)
All (I hope) know that making HF measurements using probe GND wire give very bad effect. So normally we use some kind of tip end what connect GND directly. (With Hantek probes there are not these any included in package, not even small "spring" style what price is 1/100 yuan)
This test do not tell anything about this situation when use "long" GND wire.
For some compare I make also test with Agilent/HP old "not bad" probe with Hantek.
Both probes LF compensation I make for exactly same square shape with scope own 1kHz signal.
Hantek P150 probe (labeled as 100/6MHz).
Now with 1:1 setting. Signal 0,5 - 10MHz.
Same hantek probe 10:1 setting. Signal 1 - around 280MHz
I use step sweep and stepping is stopped after around every 50MHz advanced as "poor mans markers".
same test but now HP/Agilent "150MHz" probe 10:1, sweep stop around 250MHz (sorry, my mistake)
Hantek P150 probe, now mediumfast rising and falling pulses. (pulse generator specs: rise and fall time <=1.3ns not good but enough for this purpose)
(if all is exactly ok, pulse looks symmetric... so there is not perfect frequency response over 0 - 1GHz /
But there is scope freq response shape with probe together and lot of transmission line mismatches and also pulese generator itself is not perfect. It is HP8161A with "fast" option (not 50MHz model).
Same test with HP "150MHz" probe. (littlebit better pulse shape but not big advantage. DC/Ac do not make any difference with this pulse freq)
Conclusion: Not bad. In this price class Hantek with own probes is really good. It is not Tektronix, it is not Agilent but... it is reasonable good scope for normal hobby and also professional use for signals under 100MHz.
(also I have make fine adjustment for CH1 and 2 compensation capacitors (inside scope front end) as perfect as I can do but this do not affect these probe tests becouse all they are made using scope lower voltage band.)
Also I test with probe own GND wire. (later pics - but both are really bad (of course) and nearly as same class)
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So if you do not really need advantage what mod may give, do not mod a: if you want factory 3 year warranty, b if you are not sure how to do mod. (fail may give lot of troubles - but still it is "repairable" if you follow exactly what all information you can get reading carefully this forum... in this case Rigol is littlebit different)
But remember, samplerate do not go faster.
This is also very good scope in its price class.
(with mod you get 2ns/div but scope is just same speed, it is only "zoom". You can do it with computer... draw nev vlines with 2ns/div and stretch picture with irfan wiev or other. It gives just same effect. Scope real speed is just same before and after mod.)
Understand aliasing specially if use FFT. With this kind of freq response shape there is lot of and littlebit more aliasing.. nearly as garbage collection. And modification make it more bad. Lot of more bad. If want make good, it need do just opposite as modification. It need reject BW and make it more like brickwall shape. (but who cares FFT quality... maybe not so many)
If you use scope in high temperature. Room temperature high or if air do not flow very free around scope.
Maybe it is good in this case install small fan inside scope. (no need full speed, you can reduce nominal speed example x0.7 - 0.9 (depends fan type and quality) and you get low noise and it still helps airflow inside scope. It need only small extra amount of air. (example double speed if compare natural free air flow and exance rate) In this case I recommend fan take outside air and flow is to inside. In this case you can put small filter before fan so all dirty do not free travel to inside. In normal 22Celsius room temp some components work quite high temp. Clearly over 70C case temperature. It is not good to go any more high. They may last but maybe fail rate start grow.