Giveaway of the fastest Hantek DSO5062B in the world!

[tatus1969]

I've just upgraded to a more modern 4-ch scope, and told him above that I am now prepared to release him and let him find a new home.

A few words of his behalf:

He is a bit aged and could need some health care: his channel A seems to need a touch up of the modifications that I gave him - most probably a cold solder joint from thermal cycling. It works most of the time and I have been using it daily until yesterday.

The topic is is meant like this - AFAIK, he is just that: https://www.eevblog.com/forum/testgear/hantek-tekway-dso-hack-get-200mhz-bw-for-free/msg979548/#msg979548

He even had an appearance on "TV":

I thought I'd make a totally biased and unfair giveway: I'm giving him away and just want to have my postage paid (UPS from Germany). Just post please what you need his ridiculous 250MHz bandwith for 

[capt bullshot]

I thought I'd make a totally biased and unfair giveway: I'm giving him away and just want to have my postage paid (UPS from Germany). Just post please what you need his ridiculous 250MHz bandwith for 

I'd give him a try with the Leo Bodnar fast rise time pulse generator to see if it performs better or worse than a vanilla Tek 200MHz DSO. And postage from Germany to Germany shouldn't be too expensive anyway. Next I'd just put it onto the pile of TEA ... is this biased and unfair enough?

Of course, I'd post the results here.

[tautech]

Bump for tatus1969

And just one member wants his generous offer of a free DSO ! 

[capt bullshot]

Little competition here, anyway, I've decided to build up some more biasing:

I'd offer an heavily used and somewhat damaged (but still useable) Hioki (Yokogawa branded) 10MHz / 150A current clamp as a swap item for the ridiculously fast Hantek. For no particular reason (except this forum) I believe you might find this thing useful. The item failed calibration at low frequency. It's some percent low at lower (< maybe 1kHz) frequencies, but still OK at higher frequencies, most probably due to a slightly damaged core. The clamping mechanism is worn out, but cable ties help.

https://www.hioki.com/en/products/detail/?product_key=5724

It requires an external +/- 12V supply and a maybe expensive LEMO connector.

[tatus1969]

Should I say "and the winner is!..." (any guesses)? 

Capt bullshot, thanks - that's a very welcome swap for me (for no obvious reason  )!

[ResistorRob]

I'm going to cry that I missed this, lol.  I've been wanting to get an oscilloscope for years, but a string of bad luck keeps me in the poor house!
I'm willing to sell my kidney on the black market for a Siglent 1104X-e 

[tatus1969]

I'm going to cry that I missed this, lol.  I've been wanting to get an oscilloscope for years, but a string of bad luck keeps me in the poor house!
I'm willing to sell my kidney on the black market for a Siglent 1104X-e 

Bummer... I closed this "contest" early because there was little response. If you go for a Siglent, then make it an SDS2074X - these are also hackable just like that Hantek (althrough this is an analog stage circuit hack which voids the warranty). I got mine for 768€ (net, display model) and am very happy with the 300MHz 4ch scope that I have now (sorry tautech ). These scopes are amazingly fast and feel rather like a real analog scope.

[capt bullshot]

It's arrived, so as promised the results of the comparison Tek vs Hantek on the Leo Bodnar fast pulser:

https://www.eevblog.com/forum/projects/yet-another-fast-edge-pulse-generator/msg2552778/#msg2552778
The waveform looks pretty nice there.

Using the signal generator, CH1 shows a -3dB BW of about 200MHz, CH2 about 230MHz.
It's not very usable at these frequencies, since the displayed traces are quite unstable, I guess it's due to the sin(x)/x interpolation that cannot be turned off (except in equal time sampling mode) and the rather poor trigger jitter. One has to turn on averaging to get a stable result.

The 10MHz square wave looks ringing where it isn't, same sin(x)/x issue.

[tatus1969]

Using the signal generator, CH1 shows a -3dB BW of about 200MHz, CH2 about 230MHz.
It's not very usable at these frequencies, since the displayed traces are quite unstable, I guess it's due to the sin(x)/x interpolation that cannot be turned off (except in equal time sampling mode)

Exactly. Their sinx/x filter also seems to have wrong parameters, because it's that what's limiting the available BW in the end. That's why I made all my rise time measurements with equal time sampling mode, you get a dot cloud then and have to use cursors to manually measure the rise time (or BW with a function gen). Would be curious if you get my advertised ridiculous BW then 



By the way, I also got your current clamp. Looks awesome! Now have to get that plug, or decide to snip it and put sth different on.

[capt bullshot]

I did the rise time measurement in ETS mode, see the other thread.

I've repeated the CW bandwidth measurement in ETS mode, results see pictures. The signal generator was set to 10MHz, and output amplitude adjusted to a 200mV RMS reading on the scope. Then the amplitude was increased by 3dB and frequency cranked up until the reading was 200mV again (peak of the sine wave was at the same grid line).
It's 200MHz and 230 (maybe 240) MHz again.
Using averaging instead of ETS gives nicer waveforms and quite similar amplitudes. There's some other "interesting" stuff going on: Set to 4k Samples and averaging, it shows a nice waveform at 200MHz. Now set the memory to 40k or more, and the waveform kind of collapses.

Edit:
Risetime (20/80) using the cursors results in 2.2ns and 1.95ns, roughly the same as the built-in measurement.

[tatus1969]

How have you connected the signal gen / pulser to the scope, did you use my 50 ohm adapters that I had sent you? They are required to achieve the 1.5ns target.

[capt bullshot]

I'd used one of my own 50 Ohm feedthrough terminators and got these results.
A few minutes ago, I did repeat the test using one of yours, and I've got 1.5ns risetime using ETS and the cursors.

But using the signal generator, the BW is less with your terminator, and the amplitude was wrong (had to set the generator to a lower level to get the same 200mV rms). So, I measured your terminator, and it's 100 Ohm 

This works with the pulse gen, since it's directly connected to the terminator and the scope (no cable at all), but not with the sig gen, the cable impedance mismatch creates some bumps in the frequency response.

Tested your 100 Ohm terminator at my fastest scope (1GHz TDS580) with the pulse generator: 16% overshoot, 0.53ns rise time.
My 50 Ohm terminator: 28% overshoot, 0.33ns rise time
Another 50 Ohm terminator: 31% overshoot, 0.4ns
Internal 50 Ohm termination: 11% overshot, 0.29ns (posted this somewhere in the Leo Bodnar pulse gen thread)

[capt bullshot]

So what's inside your terminators? I'm really tempted to open them up.
Both show 100 Ohm with the DMM (DC resistance), one shows 50 Ohm on the TDR, the other one 94 Ohm.
Now, that's too much of possible permutations to find the best frequency response, since I don't know which one of your terminators I've used to determine the -3dB BW.
Anyway, using another (homebrew) fast edge generator, I found that other "interesting" behaviour again:
With 4k memory selected and averaging active, the difference in rise time to equ time mode is rather minor.
Increasing the memory depth setting, the rise time gets notably slower 
Looks they've done something wrong in the firmware ...

[tatus1969]

But using the signal generator, the BW is less with your terminator, and the amplitude was wrong (had to set the generator to a lower level to get the same 200mV rms). So, I measured your terminator, and it's 100 Ohm 

Sounds like it has gone bad internally, I made it from two 100 ohms resistors in parallel. Do both of them measure 100 ohms?

Now set the memory to 40k or more, and the waveform kind of collapses.

The firmware seems to be somewhat indecisive regarding the sinx/x parameters, sometimes it even flips between two filter BWs at the very same setting. Almost as it would try to judge what make sense most.

Risetime (20/80) using the cursors results in 2.2ns and 1.95ns, roughly the same as the built-in measurement.

That's puzzling me, I was definitely measuring 1.5ns and my pulse generator was slower than Leo Bodnar's (~ 500ns). I dug up my latest modification pdf and attached it here. Could that be also related to the vertical gain? The scope uses one of these digitally controlled PGAs so the BW can depend on the vertical setting. And I also used a vertical setting that does not have the relay based attenuator in the path. I just saw in my document that I even managed to get 300MHz in conjunction with active probes (last page).

[tatus1969]

So what's inside your terminators? I'm really tempted to open them up.

That's a rebuild of an idea somewhere here in the forum, using stock BNC stuff and adding ceramic resistors to the path.

[capt bullshot]

Checked the terminators again: One is 100 Ohm all the time, the other one shows an intermittent failure: sometimes 50 Ohm, sometimes 100 Ohm. Looks like one of the resistors is broken.

So using the slower homebrew pulse generator (with an differential PECL output stage),
I can see 1.5ns on CH1 with my 50 Ohm terminator and get the very same trace with the one of yours when it decides to be 50 Ohm. With the 100 Ohm one, I get a slower risetime - but in contrast to the Leo Bodnar pulser which I did directly plug onto the terminator, here's a short (15cm) run of coax cable involved.

Anyway, enough confusion for today ...

[capt bullshot]

One last test for today:
On Ch1, with the internal attenuator switched into the path (500mV / div and greater ranges), I can achieve 280MHz BW vs 200MHz with the attenuator out.
On Ch2, there must be something gone wrong, since the BW drops below 200MHz and shows at some frequencies a distorted signal.

Now testing with the Leo Bodnar pulser, I get 1.4ns on Ch1 and heavy ringing on Ch2 - clearly something is bad here.

So, yes it's ridiculously fast and the fastest Hantek DSO5062B in the world!

[tatus1969]

Now testing with the Leo Bodnar pulser, I get 1.4ns on Ch1 and heavy ringing on Ch2 - clearly something is bad here.

I've never seen such behavior, that must have happened during transport. It's not too unlikely because some of the modifications that i made were very tricky and might not be long lasting:

So, yes it's ridiculously fast and the fastest Hantek DSO5062B in the world!

[tatus1969]

I finally had the time to put my new current probe into service, but only after having upgraded it Thanks again capt bullshot, much appreciated!
I was a bit worried of using a switching converter, but my scopes confims 23mA(rms) measurement noise, which perfectly matches the specified 25mA(rms) of the current clamp.

[capt bullshot]

At work, we've got several homebrew supplies for them, all made with a simple 230V -> +/- 12V SMPS module and no additional filtering - never noticed issues with that.

Anyway, your DC/DC might be a little weak (depending on the max. current you want to measure), the spec says:
Power supply   ±12 V ± 1 V, 5.5 VA max.

Due to the compensation method, one must assume that the current draw isn't symmetrical or constant, but vastly dependent on the measured current. For a large DC current or a current pulse I'd expect the clamp to draw up to (ballpark) 0.5A off one rail (don't know the internal turns ratio, but they're using a 1A capable Power Op Amp to drive the compensation winding).

[tatus1969]

Ouch, as this also means that I might trip USB overcurrent then. Good to know, thanks for pointing that out. I'll keep an eye on that!

[tatus1969]

new current probe at work