Video Review & Teardown of the Analog Arts SL987 USB Combo Instrument

[nctnico]

1GHz with a 100MSa/s ADC is not completely impossible. You may use a comparator and a TDC to determine the exact triggering instant and then accumulate over multiple acquisitions. HP did that in the 54600 series and manged to get >100MHz bandwidth out of a 20MSa/s ADC.

As I mentioned in the video, such a system requires either a coherent precision time-base signal or an entirely different architecture. The problem arises from the fact that the instrument makes mistakes on computing the actual frequency of the signal being applied once it is above Nyquist. And it can only do this on periodic signals (and if the period fits within the captured memory). It is essentially trying to reconstruct the aliased signal from multiple periods.

IMHO the oscilloscope bit isn't much and the claim of 1GHz is way overstated. Without 50 Ohm inputs that is impossible to achieve. BTW: about a decade ago I've made something very similar (see my avatar picture) with up to 1Gpts per channel and 10 bit resolution. I cancelled that project due to Rigol introducing cheap oscilloscopes.

It's a pity the reviewer didn't go deeper into the logic analyser and more importantly the pattern generator. If I look at the prices the logic analyser and pattern generator capabilities are interesting. I'm still looking for a good digital pattern generator solution which can generate UART, SPI, I2C, etc patterns from a simply GUI.

edit: typo

[nctnico]

I downloaded & installed the software to have a look at the pattern generator part. It is pretty basic. It allows to generate sine and triangle waveforms and set/clear signals to 0 and 1. However the way signal generation is implemented is rather clumsy. You have to select a function and then click which bit of that function is to be put on a certain signal. Also no way to set the output level which made me loose interest in this device.

[zapta]

In this episode Shahriar takes a close look at the Analog Arts USB based mixed-domain instrument. The SL987 offers an oscilloscope, arbitrary waveform generator, FFT-based spectrum analyzer, pattern generator and logic analyzer in a compact form factor.
The teardown of the unit is presented along with the datasheet of every major component on the PCB. Some design limitations and concerns are presented along with basic performance verifications.

Excellent review. I liked the depth and the style. Thanks for doing it.

[JasperNL]

It would have been interesting to hear what you thought about it. As I said, I feel bad about the review and I have given them a chance to address the issues and get back to me.

Don't feel bad about it. I like the way you reviewed this piece of junk. First the block diagram with the theory of operation. Then you compare the used components with the claimed specs. At his moment you discovered some major problems with the system architecture. Finally you take some actual measurements to confirm the problems. Thats just perfect. You discovered the problems before you turned it on
You point out the problems, gave the benefit of the doubt and the chance to solve the problems. Analog Arts should be lucky with your gentle review! 

[Hugoneus]

I have to say, this review has caused a lot of headache! The YouTube comments are     

I added my observations to the comment section too. A $1260 dollar product should be a serious product in my opinion.

A kind EEVBlog member has pointed that people who are questioning my review have had their account created on the day (or the next day) the review was released. How disappointing...

[MadTux]

WTF, 1260$ for a 50MHz Scope and a AWG with broken offset and a 15MHz square wave that looks like a sine wave?!! LOL. 150-250$ would be more appropriate. Any old HP 16500 will beat that thing for a fraction the price.

Maybe someone should create a list of equipment you wouldn't want to buy (D-105 reference, that thing, HP instruments with German HP ASICs inside, HP 8116A, 8112A etc. ....)

[macgyver0815]

That review made my day - thank you Shahriar   
Please don't feel bad about the reaction of that company (and their troll postings on youtube) - it was an honest review and in my opinion you were VERY polite and they should be thankful for that.

What reaction did they expect from an expert that can even track down issues in $50k microwave equipment?
I guess they haven't watched your other videos before sending you the unit for test

[JoeN]

I finally just got to this review.  I just stopped 8 minutes in to see if anyone here had commented on it so far because I thought there might be a comment or two.  I'm not sure I can even continue.  I have never been a fan of "cringe-comedy" - it's hugely unpleasant for me to see Jack get embarrassed by his own self for the 100th time (Jack Tipper, not Jack Bauer).  I'm getting the same feeling now watching this video and it makes it hard.  How the heck did they manage to melt a relay?

[amyk]

For a company that claims:

Analog Arts is a private high-technology company headquartered in Massachusetts, USA. Formerly known as Edge Technology, the company was founded in 1992. It specializes in high performance digital and analog signal processing and advanced test measurement systems. Analog Arts products range from custom board level solutions to complete stand-alone equipment. Throughout its history, Analog Arts has been committed to offer reliable and cost effective solutions to challenging ideas. Relying on a pool of highly experienced and motivated scientists and engineers, Analog Arts has become a world resource for outstanding engineering. As a recognized leader in signal processing and measurement equipment, Analog Arts has provided designs, products, and services to scientific, military, and commercial companies throughout the world. The company designs, develops, tests, purchases parts, manufactures, and packages all products in the United States.
We customize our technology for particular applications. With features like, 140 dB of dynamic performance, 100 GHz sampling rates, 28 bits of resolution, and super high bandwidths, our solutions have satisfied a wide range of applications including radar, communication, automotive, medical, and satellite.

You have to wonder how they could be this incompetent?
$1260 and the best and most expensive product in their range? Yikes.

I agree, this seems more like what some random Chinese company would do...