Title is misleading. This is not a 4-channel oscilloscope in the classical sense. Should be called a 2-channel oscilloscope + 2-channel logic analyzer.
Nonetheless, it's perfect for small hobby projects and the price is right.
I don't understand why they only have 4KSamples Storage per channel. The ARM chip should be able to handle more RAM.
Specially for the Logic analyzer part. If you want to analyze some serial protocol (Serial, SPI, I2C etc.) you are really limited with only 4k.
I use now the Logic Analyzer from http://www.saleae.com/ It's a dumb device and everything is done on the PC. But for simple applications it works fine.
Actually, it's specced out at 72MHz max sample rate. The actual bandwidth spec is usually higher and is dependent on the ADC. Would be nice for the OEM to spec out the two separately.
Yeah, actual (acceptable) bandwidth is probably close to 1/4 the sampling rate. They're fudging terms around here. It's probably somewhere close to 20mhz analog bandwidth.
Specifications and reliability. Industrial vs. commercial spec parts, wire wound resistors, temperature compensation devices, 5ppm oscillators, lots of reasons.
Some of the old tektronix wiring really is a thing of beauty. The tektronix 360 modules are so lovely.
A few years back I managed to buy a cheap digital voltmeter that was actually wrong. As in: consistently off by 20% or more when measuring voltages in the range of volts. (!)
Ever since I've been trying to figure out how much to spend to get a voltmeter that is guaranteed not to suck. I figure it probably still needn't be very much, but I still haven't chosen one, because I've managed to spook myself. I tell you, on the day after you catch your test equipment giving you egregiously bogus misreadings it is hard to resist the impulse to spend the money on a Fluke or Textronix.
I bought a $50 microcontroller based DMM (much better than "dumb" dmms) from circuit specialists forever ago here:
http://circuitspecialists.com/prod.itml/icOid/9455
It works really good. Comparable to fluke handhelds but not in the same league as the fluke 4/5 digit bench DMMs.
Keithley stuff is great too, more science based though. I've used everything from their picoammeters to their general purpose DMMs.
Apart from the accuracy, build quality, etc. one of the reasons I bought my Fluke DMM is that I was working with some high power circuits (like 600VDC at 60+ amps) and I trust the Fluke more than a random cheap meter not to blow up. There's a reason the fuses for a good multimeter cost more than the average discount instrument.
That is only a part of the story for medical tech. The stuff would be expensive even if sold at cost.
In my experience, medical devices cost a lot to make because a lot (if not most) of the hardware is custom, the amount of required testing and documentation/traceability is stupendous, and the sales volume is comparably low.
The high manufacturing cost (per unit) combined with the high fixed cost (per product) drive the prices up pretty quick.
Their stuff is hackable - the previous 2 channel oscilloscope they made got incrementally more features in it's firmware revisions, and they published the code- see here: http://code.google.com/p/dsonano/
They're a startup, based in Hong Kong (last I checked).
Seeedstudio makes neat stuff, and they're part of the whole electronic hobbyist renaissance (along with sparkfun, Make magazine, etc.) They offer neat stuff, at good prices.
It's perfect for what it's intended for. Audio frequencies and sub 1MHz signals (so I can watch servo outputs and PWM signals from Arduino or RC gear, but not RF or processor bus stuff).
I'm not _quite_ interested enough to save ~$50 by being a beta tester, but if the early reviews turn out positive and it seems this'll let me watch signals on 16MHz microcontrollers I'll happily fork out $200 for one later.
Perhaps this isn't "web startup/entrepreneur" relevant news, but it's _certainly_ "hacker" news...
New ones are, but I got my Tektronix 2430A for free (with all opts) because someone was getting rid of it. Usually you can grab one for around 300. More importantly, it can still be calibrated, traced to NIST, it has a higher bandwidth, and I know that my probes are all going to be up to spec without capacitance problems. On the other hand, it's a lot bigger than this device, but I'd say it's probably just as reliable (and probably still more serviceable). No Math/FFT stuff though.
tl;dr: I'd get this for convenience or as a second device, but I wouldn't really trust it.
Not any more, you can get chinese 2 channel 50-60MHZ DSOs for $250. If you do your homework you can find the same ones that are badged HP or Agilent here
Basically, Rigol spec'd out a 100MHz scope and then crippled it in software to have a cheaper 50MHz model to sell without having two separate hardware lines.
> Basically, Rigol spec'd out a 100MHz scope and then crippled it in software to have a cheaper 50MHz model to sell without having two separate hardware lines.
Agilent is about to do the same thing. Based on some leaked sales collateral they are pitching software upgradeability of bandwidth as a selling point for their upcoming line of entry-level oscilloscopes.
(Hmm, Agilent is currently rebranding the Rigol scope in question as their entry level. I wonder if Rigol will be building the new line for them?)
Nonetheless, it's perfect for small hobby projects and the price is right.