I haven’t written in AEONS! And I figured, “Hey! What better way to begin my two-zero-one-zero archive than by bragging…..oops!….I mean blogging about one of my new acquisitions”. I’ve recently bought myself a DSO. Not the fancy Agilent or Tektronix scopes; I bought myself something much more affordable – a DSO2090. I’m pleased with it. Very pleased. And, since there are very few reviews about it online, I’ve decided to write one.
I had initially decided to build my own DSO, but as I soon found out, building test and measurement equipment is no child’s play. I tried in vain to get my hands on a decent ‘scope on eBay, but most of the scopes were out of my budget, and the ones that were in, wouldn’t ship to India. A lot of manufacturers make USB scopes – PicoTech and BitScope being the notable ones. But again, too expensive. And I really got sick of trying to use my soundcard as a low cost ‘scope. So after much forum-trawling and late night ‘research’ I settled on the DSO2090. Do note that the price of this instrument can vary from 160 bucks to over 300 bucks on the net!
The ‘2090 is a good piece of equipment. It’s priced reasonably well (obviously, a lower price would be better! :-P), and it has most of the functions that higher end DSOs have. A few words of warning – don’t expect the ‘2090 to match up to a dedicated bench DSO. The ‘2090 is more like a tool that the moderate-to-advanced-level hobbyist, rather than a test engineer at Texas Instruments, would have.
Ripped from the seller’s (www.getbetterlife.com) eBay page
I still haven’t test driven the socks of the DSO, but I have managed to get my fingertips dirty. Read on for the lowdown.
The ‘2090 is a USB driven, two channel digital signal oscilloscope. Mine is a Hantek clone. It can measure at 100 megasamples per second (MSps), and has a bandwidth of 40MHz (for a nice explanation about the difference between sampling rate and bandwidth go here, and also read this).
- 100MSps real time sampling
- 2.5GHz equivalent sampling (also called ‘ETS’)
- 40MHz (-3dB bandwidth)
- 8 bit resolution
- Max input voltage 35Vp-p
- Vertical deflection: 10mV – 5V @ 1x probe (9 steps)
- Horizontal deflection: 4ns – 1hr (38 steps)
- Trigger: external, or either channel (edge based, single, normal)
- Several convenient measurements (P-P, frequency, RMS, etc)
- Math (add, subtract, multiply, divide)
- Saving screenshots (JPG, BMP
- Logging (DAT, Word, Excel)
- Nice demo function
- Other useful features
I ordered my DSO2090 from a China-based site. The cost was the lowest from among all the web-based dealers, AND more importantly, shipping costs weren’t atrocious. The base price was USD161.20, and shipping was USD29.71, for a total of USD191.91 (~INR 9,324). Customer service on the site was very prompt and courteous. Shipping to Gurgaon, India, took a little long – 10 days. But in all fairness, it was the Christmas week. Packaging was very good, and the DSO came unscratched and unharmed. I had no issues with customs (both Bombay, and Delhi released the parcel in less than 3 hours).
The scope is totally USB driven – no external power required. The cable supplied is a USB ‘Y’ type cable – One for power and data (black), and the second (red), to supply additional power, if necessary.
Two BNC clip probes and a few probe accessories come as part of the kit. The probes supplied are compensated 1x/10x probes. Considering the price, they’re very good quality.
At the back of the scope there are two metal tabs – “Ground” and “Cal”. The calibration tab gives a 2Vp-p square wave at 1kHz.
The body of the DSO is plastic, and build quality is fairly good.
As with almost all digital T&M equipment these days, the ‘2090 can be interfaced with custom software. As a bonus, sample C++, VB, and LabVIEW programs are included on the driver CD.
Below are a few screen shots of some measurements.
A 50% 6.13kHz PWM from the Super Probe that I built some time back.
What the DSO2090 is NOT:
- a Tek or an Agilent ‘scope
- a full-fledged DSO with benchtop features
- a standalone device
- a super-accurate device that you can trust your life (or other’s lives) on
What the DSO2090 IS:
- an awesome hobby ‘scope with lots of features
- a very low price test and measurement device
- very portable
- a very cool device that will enhance your geek image
The final word? If you’re a poor student hobbyist like me, and have reached the stage where you ‘absolutely need’ a way of seeing what signals are zooming around in your circuit, then the DSO2090 is certainly for you. There are variants to the ‘2090:
- the DSO2150 (150MSps/60MHz)
- the DSO2250 (250MSps/100MHz)
- the DSO5200 (200MSps/200MHz)
- the DSO5200A (250MSps/200MHz)
I find that the ‘2090 is the best value for money, and it fulfils my need, at least for now :-D . A recommended buy for those looking to purchase a ‘scope.