Några veckor tillbaka publicerade vi en kort artikel om den nyligen släppta Keysight 1000X, ett oscilloskop som markerar Keysights sent men välkomna tillträde till den hacker-centrerade postnivåmarknaden. Förståligt utlöser detta intervall en stor spänning, eftersom det lovar att få några av den avancerade stamtavlan av den allmänt kända 2000x samt 3000x mönster ner till ett mycket budgetvänligt pris. Nu kopplar det med möjligheten att hacka sitt bandbreddslås, liksom allt detta väsen är väl motiverat.
[Dave Jones] från Eevblog fick händerna på en, såväl som att genomföra en UART-dump såg sortimentet 200 MHz bandbredd trots att det var märkt som en 100 MHz-modell. Han fortsatte sedan att hacka primärkortet för att låsa upp ett ookumenterat 200 MHz bandbreddsläge. Detta gav en stor förvirring: några angivna [Dave] fick en “pre-hacked” -version, andra antog alla 100 MHz-versioner verkligen ha en lagerbandbredd på 200 MHz.
Vid sidan av bandbredds oro undrade många hur det skulle gå mot den nuvarande inträdesnivåstandarden, Rigol 1054Z. Är extra kostnad samt färre kanaler värda Keysight Badge?
Keysights svar på våra frågor såväl som förvirring var garantin att skicka oss en utvärderingsenhet. Tja, efter att ha tagit det såväl som att leka med det, har det tydligt en hel del Keysights high-end excellens trickled ner till den här nedre versionen. Men den här enheten var inte utan några dumma firmware-problem och Damning System Crashes! checkas ut på hela utvärderingen nedan.
Utanför lådan:
Förutom räckvidden innehåller lådan en nätkabel, två sonder, ett bra ljust gult kuvert, inklusive kalibreringscertifikat samt en vänlig pekare att det är riktigt keysight nu och inte Agilent eller HP. De medföljande proberna är trevliga. Silikonledarna känner sig riktigt bra för beröringen, liksom är en trevlig förändring från den styva PVC-isoleringen som vi utnyttjas. Probe-specifikationerna är inte något spektakulärt, du kan byta dämpning mellan x1 såväl som x10, såväl som kapacitiv förpackning i x10-läget är en måttlig 10 pf.
Intressant är att alla 100 MHz variationer av intervallet är misstänkta med 200 MHz-sonder som standard, men återigen hänvisar till högre än annonserad bandbredd. Är den här smarta annonseringen att motivera hackning den till lås upp det ofokumenterade 200 MHz-bandbreddsläget, eller bara en knep för att avskräcka den 70 MHz-varianten som endast levereras med 75 MHz-prober? Oavsett avsikt är det en lovvärt gest.
Första intryck såväl som layout
Som någon som har en Rigol DS1054Z, tog den 1000x responsiviteten mig överraskad. Detta intervall är snyggt. Alla menyerna är snabba, liksom det inte är uppenbart trögt om skärmen är rörig med båda kanalerna, FFT, samt en mattefunktion. Det är uppenbart att den ganska lägre samplingsfrekvensen såväl som bandbredd visar sig vara en promenad i parken för den medföljande megazoom Asics, annars vana vid en mycket mycket mer grusande bearbetning i de högre slutområdena. Vem som helst som hatar det tröga svaret som uppstår när motstånd av vågformer på lågsändningsområden välkomnar all denna hastighet.
Väl utlagd: Analysalternativen noggrant grupperade
Menyerna samt val är utlagda extremt och är pragmatiskt grupperade. Förstå HP har gjort scopes eftersom tidens gryning, det här är definitivt ingen överraskning. Knapparna svarar exakt som du förväntar dig, såväl som mycket mer betydligt är konsekventa över räckvidden. Om du till exempel trycker på såväl som håller en knapp, som motsvarar någon typ av alternativ / funktion i alla typer av menyskärmar visas en hjälp som diskuterar valen samt belyser alla typer av detaljer.
Dessutom navigerar en dubbeltryck alltid dig till föregående meny. Alla variabla ingångar är färdiga med en enda roterande knopp. Accelerationsapplikationen är utmärkt, infact det allra bästa jag har sett på ett räckvidd. Alla roterande knoppar har en mittknapp, vilket gör det extremt intuitivt att ställa in standardvärden om det behövs.
Den tidigare generationen av sortiment av inträdesnivå plågades med skrämmande skärmar med låg upplösning. Tack och lov har detta förändrats såväl som 1000X har en bra stor skärm som är skarp såväl som tillräckligt ljus. Det är verkligen tröstande för att se marknaden kollektivt omlokalisering bort från små tvivelaktiga skärmar i nedre ändoffer.
Math-funktioner
Matematikfunktionerna är inte något markbrytande. Du får alla typiska matematiska funktioner du kan förvänta dig såväl som några fascinerande andra. Du har två resultat som du kan arbeta med: f (t) är den visade matematiska funktionen medan g (t) är en mellanliggande matematikfunktion, att efter att ha definierats en gång kan användas inom vilken typ av efterföljande matematiska beräkningarna. Det här är inte något nytt men jag gillar den metod de har gjort det. Rigol gör till exempel dig Redefine the intermediate function for each different operator, which is unnecessarily convoluted.
One of the extremely fascinating math function included is the low Pass Filter. view the video below, to see the range demodulate an AM signal, utilizing only the math functions!
Can you discuss why this works?
Bandbredd?
Bandwidth: 133MHz
Right, lets get this out of the way. What is the out of the box bandwidth of the 100 MHz version anyways?
To test this, I’ve utilized my reliable Marconi 2030 RF Signal Generator to output a 1 V Pk-Pk signal. I then determine the -3 dB (0.707 V) point on the scope.
The bandwidth measurement concerns about 135 MHz, an expected security margin for a 100 MHz scope. Out of curiosity, I determined the amplitude at 200 MHz as well as it concerned about -7 dB (0.45 V).
Overachiever: frequency Counter
Whilst investigating the out-of-the-box bandwidth, I was pleasantly amazed by the hardware counter in the scope. I thought, like the Rigol 1054Z, it would begin to stop working around 100 MHz: wrong! I cranked up my RF signal generator method beyond the -3 dB point of the range however the hardware frequency counter continued to work. In fact, it worked absolutely fine as much as about 435 MHz! I suspect this would continue to work even higher, as well as was primarily restricted by the falling amplitude because of the restricted range as well as probe bandwidth. It would be fascinating to see exactly how far it continues to work in the 200 MHz “unlocked” version.
Waveform Generator as well as training Signals
The 1000X includes a rather capable built-in 20 MHz function generator. Not only can it produce all the typical square, sine as well as triangle waves however likewise has a 20 MHz noise waveform, a pulse, as well as even just DC. The generator can swing between +/- 12 V into a high impedance load, so any type of amplitude as well as DC balance out combination within that variety is valid. The output impedance is 50 ohms, therefore the output drops to +/- 6 V for a 50 ohm load.
Rather disappointingly, the sine wave is the only waveform that goes to the full 20 MHz. The square as well as pulse waves are restricted to 10 MHz, as well as even then they look awful. The ramp wave goes as much as a simple 200 kHz. This is a 20 MHz generator, as well as no more.
A extremely great addition to this is the capability to apply different modulations to the sine as well as ramp waveforms. You can do FM, AM as well as FSK with variable modulation depths. It’s great fun to observe the spectra of the different modulated waveforms on the FFT!
Closely associated to the wave generator are the training signals offered on the probe calibration connector. These signals are intended to shed light on a variety of waveforms that a beginner can expect to find across as well as provide you a possibility to polish up your set off configuration skills. For example, you can see the impact of noise coupled into a waveform. A great method to test your FFT skills as well as modulation theory is to try one of the RF waveforms. The different digital as well as glitch waveforms assist you comprehend the much more obscure however powerful triggering modes on the range such as envelope triggering in pass/fail mode. numerous of the training waveforms likewise let you modification parameters.
Seeing that the training signals contained much much more fun waveforms compared to the actual waveform generator, I rather slyly, tried to utilize both at the exact same time. Unfortunatey, this did not work. You cannot utilize both the training signals as well as the waveform generator at the exact same time. As the training signals include a great deal of arbitrary signals it is remove Keysight are routing the waveform generator to the calibration connector as well as leveraging the DDS-type generator employed for the arbitrary waveforms.
This made me think, is it possible to somehow customize the data system as well as include your own arbitrary waveforms? Examining the inbuilt file-system exposed some data with “.arb” extensions that cannot be checked out or written to. Nonetheless, it is remove that even though the waveform generator does have the capability to produce arbitrary waveforms, this is disappointingly restricted by Keysight. For example, the generator on the 3000 X-Series, with otherwise similar specs, enables you to specify arbitrary functions. I bet the 1000X has the exact same hardware, albeit restricted out of caution to avoid unnecessary toe-stepping of the higher end market.
Frequency reaction Analysis
FRA: common Setup
One of the features I was truly thrilled about was the frequency reaction Analysis. This is essentially a stripped-down version of the Power analysis Module offered in the 3000 X-Series scopes. It can allows you utilize the interior waveform generator in conjunction with both channels to determine the frequency as well as phase reaction of a circuit, from DC to 20 MHz. Although alittle range, this is a very great function to confirm audio grade filters, opamp GBP, PLL loop filters, as well as so on. The dynamic variety is extremely impressive, I have determined it working fine down to about 20 uV (-79 dBm!)
So what precisely is this helpful for? let me tell you about the time it saved me a great deal of headache. I was developing a laid-back PLL loop filter; as you do I started with simulator as well as proceeded to optimise through trial as well as error by altering a few components. I discovered that a specific 1 uF capacitor in my junk bin provided spectacular results, which was not attainable with the other 1 uF capacitors I had. So what precisely is going on here? exactly how might I see the impact of this wonderful 1 uF capacitor on the general filter?
Sweeping the filter with the special capacitor exposed a region where the acquire would plateau, purchasing me some phase margin as well as leading to a steady loop. Clearly, this capacitor had extremely high ESR. however exactly how much exactly, so this might be duplicated repeatably with one more capacitor? utilizing the markers, I determined the begin of the plateau at about 3 kHz, leading to a specific time constant as well as ESR of 50 ohms. equipped with this knowledge, I tried a different capacitor as well as added a 50 ohm resistor in series as well as voilà the loop was steady with practically similar results!
FRA: unknown however steady 🙁
FRA: understood however unsteady :/
FRA: understood as well as steady 🙂
Although an uncommon as well as thus much welcomed function for a low end scope, it is unnecessarily restricted. For example, you cant set the sweep resolution or add a DC balance out to the sweep waveform, even though the Wave Gen has these capabilities.
Furthermore, the firmware is likewise not as polished as I would expect, as it cannot differentiate a phase shift of -180 degrees from +180 degrees. This implies any type of time your phase hits -180, the plot erratically jumps to +180 leading to a very confusing phase plot. This ought to have truly been ironed out before the release.
FFT- FTW!!
Smartly grouped
The FFT or quick Fourier transform is an progressively appropriate function of all contemporary scopes. In the past, entry level scopes utilized to conceal it deep within some obscure math function menu, embarrassed by the crusty performance that would follow. now however, even low end scopes have moderate bandwidth in the few numerous megahertz, higher than needed sampling rates as well as enhanced ASIC power; all of which have enabled the FFT to be much much more usable. Infact, the 1000X is so positive of its performance that it flaunts the FFT by providing it a
physical button of its own.
The FFT function, has a great deal of adjustable parameters which is extremely great to see. You can go into a span, as well as a centre frequency, as well as it will determine as well as tells you your bin resolution. Also, not only can you carry out the FFT on either channel, you can likewise carry out the FFT on an intermediate math function! This is far far much better than the FFT offered on the Rigol.
FFT: 100KHz Carrier, 10KHz sidebands
Even though the screen is rather large, state you want to turn on two channels, carry out a math function between them as well as then carry out the FFT on the result. exactly how would you potentially screen all of those traces on one screen without it appearing like a huge mess?
This brings to light one more good function of this scope. You can turn all the channels off, eliminating any type of indication of them on the screen however still carry out all the math functions on them. This is fantastic as well as is very different to the Rigol 1054Z where you cannot hide a channel, rather only either turn it totally on or turn it totally off through relay action. The 1000X does not seem to turn the channels off physically at all. instead it just hides them. This implies if you are just thinking about taking a look at the spectra of a signal, you can utilize the whole screen, in all its glory, to look at the FFT. None of that split screen nonsense!
The FFT choice on this range is extremely well implemented apart from a few quirks. For example the scope, for some reason lets you set a rather ambitious as well as outright silly span of 500 GHz. one more bit inconvenience is the option of the colour white for the FFT waveform that corresponds with the option of text colour. If you now position the FFT trace at the bottom of the screen to maximise the visible dynamic range, you end up covering a few important parameters! I likewise discovered that the range was prone to glitch if the FFT was fiddled with excessively. Once, I couldn’t get a few of FFT parameters to vanish even after turning the FFT off, leading to mess of overlapping text strings on the screen.
Update Rate
Keysight is vi