SparkFun Forums 

Where electronics enthusiasts find answers.

All things pertaining to wireless and RF links
By kosullivan
#102975
Thanks very much! Personally I don't think the guys at Sparkfun are the kind that get too worried about that sort of thing anyway :)
Hah! I love a company that sells oscilloscopes and has the slogan "Live healthier and more beautiful life". 10 points :)
By mac
#102982
13.56 x 2 Msamples/s is the absolute minimum you need to reconstruct the signal with a sin(x)/x approximation.
In reality you need at least four times, up to 10 times the shannon limit. Why? because mostly you seek for non-linearities or higher band harmonics.

And yes 32k (in fact 14k for DSO from hantek) is small, but it's enought to cover 1400 15Mhz cycles at 10x sampling. Learn how to generate triggers, even with high end agilent scope I have to generate accurate triggers to capture small event and navigate trough long events.

And hantek DSO have a crap software, better get a rigol.
By stevech
#103145
mac wrote:And hantek DSO have a crap software, better get a rigol.
Isn't the Rigol line a LOT more expensive than, say, my $140 DS2090? The Hantek software, recently updated, is fine for my light use purposes.
By kosullivan
#103146
I've taken the risk after talking to a few different people that sell that Hantek DSO-1200 and gone with it.
I have a choice of using it standalone with nice tactile buttons and screen which has so far been the biggest criticism I've seen for USB scopes, or I can plug it in and get all the nifty software features. Finally I'm quite a traveler, so the appeal of a handheld unit is too much to resist.

I also got it for USD$688 so I'm pretty happy with the price and there's a 30-day 100% return (except shipping) policy so at least it gives me the option of seeing how good this baby will fly.
The biggest concerns I have are a) 32k memory; and b) It's a new product so I'm trusting the reviews given to me by salesmen that the people who bought it so far are happy. One guy in particular gave me fairly straight-up answers about it so we'll see how it goes once I throw a few contactless APDU's @ 13.56mhz at it!

Thanks for all the answers/debate people, I'll post a reply with my thoughts on it once I've had a good play.
--Ko
By kosullivan
#104226
Hey guys, my DSO-1200 just arrived and I thought I'd give you my first impressions.

First of all I'm really happy I paid extra for this model instead of a software-only. The user interface was generally pretty intuitive to learn and navigate around. There are definitely a few things I'll be asking Hantek to consider for a future update, but overall I'm very happy with the usability of it.

I noticed that CH2 behaves a little strangely. When there are probes attached but not connected to anything AND the scope is plugged in to the wall, there is some really noticeable noise bleeding from the power supply I presume. Simply attaching the probe ground to something or removing the DC power and this goes away however, so I can't really complain.

It's a bit annoying that some settings don't seem to save on reset, but it's firmware so hopefully it will be fixed soon and it isn't that big a deal.
There is about 1.5-2mV of ADC noise which I'm told is perfectly normal for this end of the market.

Anyway, I'm learning as I go so I may have missed something, but generally it's worked on my basic tests (monitoring RS-232, SPI, ISO7816, some misc LFO sources).

I realise there aren't any decent reviews of this sucker yet so if anyone wants me to try a quick test on it post it up and I'll see what I can do.

Cheers,
ko
By foxkid
#105659
I have a Tek 7904 mainframe, as well as a 7603 mainframe (storage scope). I pick up plugins at ham fests and on eBay.

Without doubt, the calibration stinks, and sometimes something fails. But, the total money spent is < $400. With the plug-ins I have, I'm limited to 200 MHz, although faster ones are out there.

Generally, looking at an RF signal to determine modulation problems is difficult (other than for modulation percentage of AM, which nearly no one uses). Would you use the scope simply to capture samples, and then follow with signal analysis on your PC?

Since the frequencies are low (13 MHz-ish), width is also low (< 2000 Hz?), maybe you could use a general coverage receiver and feed the audio into your PC for analysis. Many ham digital protocols are decoded this way, including some fairly sophisticated QAM schemes.

I agree, though, that there is absolutely NO substitute for a scope. An old, uncalibrated scope is vastly superior to no scope.

-- Carl