On Fri, Mar 5, 2010 at 10:52 AM, Sebastien Lelong < [email protected]> wrote:
> Hi again, > > > 2010/3/5 vasile surducan <[email protected]> > >> Seb, >> >> you are going too fast again, but that's because of your age... you'll >> cure about it after 30. >> > > If you mean after the age of 30, since I'm almost 33, I guess I'm incurable > :) > Well, let's try then after 40.... :) > > >> The toy you have pointed at isn't an 1MS/sec, but 1MHz analogic bandwith >> which is totally different. >> > > I don't understand, it's written "Max sample rate 1Msps 12Bits", doesn't it > mean 1 mega samples per second ? There's also "Analog bandwidth 0 - 1MHz"... > Yes, you have right, they probably changed the page since I've visited it (or I didn't noticed the sample rate) it was a time ago when they posted a preorder announce. I remember it has a TL082 operational amplifier on input, which is a 4Mhz bandwidth and around 13V/usec slew rate. This means an 1Mhz sinusoidal signal could be displayed OK, but I have some doubts you can see the correct rising time of an 1MHz rectangular signal. That was about. > > >> Take a look to the schematic, try to understand it and you'll see that is >> less than 500Ksample/second (my appreciation is 200Ksample per second. >> >> A decent analogic tektronix of about 100MHz analogic bandwith has exactly >> the same price... >> > > $89 ??? Where ?! > I'm browsing the ebay, last week or so a guy who bought the DSO nano, sold it after a few days since he bought it. At that time he asked $76. If you search for pictures and movies about how it works you'll find nowhere a picture with it's display at 1MHz. See here: http://cgi.ebay.com/ARM-DSO-Nano---Pocket-Sized-Digital-Oscilloscope_W0QQitemZ130371110394QQcmdZViewItemQQimsxZ20100304?IMSfp=TL100304201012r9086#ht_3246wt_754 You can find many tek which is a very decent scope (I have one of those too in my basement). The best scope for hunting noises it's the combined analog-digital scope, hard to find these days. Why? Because aquiring noise is a damn problem. Most scopes, including some high end digital Tektronix becomes stupid when are measuring low level noise (say 10-20mV), one of this stupidity is that with an appropiate timebase selection it can display a 50 or 60Hz oscillation on the crystal, when you know exactly that you have a 20MHz crystal... Then adjusting the time base you can see the real 20Mhz signal... that's called unfiltered Nyquist. So if you buy a digital scope be sure it has a good FFT, else you'll see the right hand of our God instead of noise. An analogic scope will never lie you, and almost always have a higher sensibility than a digital one, because it does not have so many aggressing signals inside (caused by the fast digital boards) and it was build in respect with EMI rules (meaning havy with iron shields and not that nowaday damn metalised plastics). Vasile > > > Cheers, > Seb > > >> >> Vasile >> >> >> On Fri, Mar 5, 2010 at 8:24 AM, Sebastien Lelong < >> [email protected]> wrote: >> >>> Hi guys, >>> >>> >>> Thanks for your replies ! "it depends on what I need", and usually I >>> reply "I don't know !"... except: >>> >>> - cheap >>> - small (a big fat analog oscilloscope really isn't an option for me, I >>> just don't have room for this, but thanks a lot Vasile) >>> - easy to use, just turn power on. I don't like USB oscilloscope, they >>> work under windows (not Linux) and always require to a laptop near >>> >>> Now the real thing I don't know is how much MS/sec I need. For instance, >>> one usage was observing power spikes. I needed this on a circuit, a friend >>> helped me debug this, I really couldn't have fixed this without a >>> oscilloscope. Highly frustrating. This is a typical usage for me. I would >>> also need to see digital signals, like i2c, maybe serial,... well, I don't >>> know, but I feel this is for a very basic usage ? I also think by using an >>> oscilloscope I would better be able to understand what's going on behind the >>> scene, visually. The fact is I'm a software guy, not an hardware guy, and >>> probably won't ask myself very complex things (most complex thing for me >>> remains Ohm law :)). >>> >>> From what you say, Mike, this 1MS/sec DSO isn't good, not serious because >>> too low right (far above 5MHz) ? Here are some I had a look at the beginning >>> of this topic, if you have any advices...: >>> >>> - http://www.owon.co.uk/pdsSeries.asp : PDS5022S and PDS6042S are >>> affordable I think >>> - http://www.rigolna.com/products_ds1000.aspx : same for DS1022C and >>> maybe DS1042C. What is interesting is you can buy separately a logic >>> analyzer module. If needed... >>> >>> >>> Cheers, >>> Seb >>> >>> PS: reading this thread, I can see I said "About crossplatform GUI >>> toolkit [...] you can >>> use wxpython (I don't like this too much)". Ah ah, Jaluinoide is built >>> over Editra using wxPython, and I now like it quite much :) >>> >>> >>> >>> >>> 2010/3/5 vasile surducan <[email protected]> >>> >>>> If you need a real analogic scope ( a russian one) I can send you one, >>>> even a french one will be less expensive than the postage.... >>>> >>>> Vasile >>>> >>>> >>>> On Fri, Mar 5, 2010 at 7:41 AM, vasile surducan <[email protected]>wrote: >>>> >>>>> NO! >>>>> >>>>> >>>>> On Fri, Mar 5, 2010 at 6:23 AM, Sebastien Lelong < >>>>> [email protected]> wrote: >>>>> >>>>>> Hi guys, >>>>>> >>>>>> Un-burying this topic, with a pocket DSO from seeedstudio.com: >>>>>> >>>>>> >>>>>> http://www.seeedstudio.com/depot/micro-digital-storage-oscilloscopedso-nano-p-512.html >>>>>> >>>>>> Only one channel, analog bandwidth 0 - 1MHz, max sample rate 1Msps >>>>>> 12Bits, but tiny, and not expensive. >>>>>> >>>>>> What do you guys think ? Sounds reasonable ? >>>>>> >>>>>> >>>>>> Cheers, >>>>>> Seb >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> 2009/1/16 Joep Suijs <[email protected]> >>>>>> >>>>>>> Hi Seb, >>>>>>> >>>>>>> The schematics is on the polish site. Enclosed a PDF. >>>>>>> >>>>>>> - I used an atmel324 - pin names are the same, numbers are different. >>>>>>> - I intend to 'upgrade' the design to support pre-sampling and 128k >>>>>>> storage (in stead of 32k) and run at 20 MHz. This means the circuit >>>>>>> around the 7400 and 4040's will change a bit and there will be a >>>>>>> stack >>>>>>> of 4 memory chips - with a decoder on top - on my board. >>>>>>> (waiting for the memory to arrive - bought them for just over 10 euro >>>>>>> including shipping at ebay). >>>>>>> >>>>>>> Joep >>>>>>> >>>>>>> >>>>>>> 2009/1/16 Sebastien Lelong <[email protected]>: >>>>>>> > Ho Joep, >>>>>>> > >>>>>>> > Looks nice ! Waiting for schematics ! >>>>>>> > >>>>>>> > >>>>>>> > Seb >>>>>>> > >>>>>>> > 2009/1/16 Joep Suijs <[email protected]> >>>>>>> >> >>>>>>> >> Hi Guys, >>>>>>> >> >>>>>>> >> As mentioned before, we're working on a logic analyser. Hardware >>>>>>> is >>>>>>> >> atmel-based, programmed in c and pc program is c#. So it is >>>>>>> off-topic >>>>>>> >> ;) >>>>>>> >> >>>>>>> >> There has been quite some progress on the C# program and we almost >>>>>>> >> duplicated the functions of the original program. See >>>>>>> >> http://code.google.com/p/protocolviewer/ for more info. >>>>>>> >> >>>>>>> >> Joep >>>>>>> >> >>>>>>> >> >>>>>>> > >>>>>>> > >>>>>>> > >>>>>>> > -- >>>>>>> > Sébastien Lelong >>>>>>> > http://www.sirloon.net >>>>>>> > http://sirbot.org >>>>>>> > >>>>>>> > > >>>>>>> > >>>>>>> >>>>>>> --~--~---------~--~----~------------~-------~--~----~ >>>>>>> >>>>>>> You received this message because you are subscribed to the Google >>>>>>> Groups "jallib" group. >>>>>>> To post to this group, send email to [email protected] >>>>>>> To unsubscribe from this group, send email to >>>>>>> [email protected]<jallib%[email protected]> >>>>>>> For more options, visit this group at >>>>>>> http://groups.google.com/group/jallib?hl=en >>>>>>> -~----------~----~----~----~------~----~------~--~--- >>>>>>> >>>>>>> >>>>>> >>>>>> >>>>>> -- >>>>>> Sébastien Lelong >>>>>> http://www.sirloon.net >>>>>> http://sirbot.org >>>>>> >>>>>> -- >>>>>> You received this message because you are subscribed to the Google >>>>>> Groups "jallib" group. >>>>>> To post to this group, send email to [email protected]. >>>>>> To unsubscribe from this group, send email to >>>>>> [email protected]<jallib%[email protected]> >>>>>> . >>>>>> For more options, visit this group at >>>>>> http://groups.google.com/group/jallib?hl=en. >>>>>> >>>>> >>>>> >>>> -- >>>> You received this message because you are subscribed to the Google >>>> Groups "jallib" group. >>>> To post to this group, send email to [email protected]. >>>> To unsubscribe from this group, send email to >>>> [email protected]<jallib%[email protected]> >>>> . >>>> For more options, visit this group at >>>> http://groups.google.com/group/jallib?hl=en. >>>> >>> >>> >>> >>> -- >>> Sébastien Lelong >>> http://www.sirloon.net >>> http://sirbot.org >>> >>> -- >>> You received this message because you are subscribed to the Google Groups >>> "jallib" group. >>> To post to this group, send email to [email protected]. >>> To unsubscribe from this group, send email to >>> [email protected]<jallib%[email protected]> >>> . >>> For more options, visit this group at >>> http://groups.google.com/group/jallib?hl=en. >>> >> >> -- >> You received this message because you are subscribed to the Google Groups >> "jallib" group. >> To post to this group, send email to [email protected]. >> To unsubscribe from this group, send email to >> [email protected]<jallib%[email protected]> >> . >> For more options, visit this group at >> http://groups.google.com/group/jallib?hl=en. >> > > > > -- > Sébastien Lelong > http://www.sirloon.net > http://sirbot.org > > -- > You received this message because you are subscribed to the Google Groups > "jallib" group. > To post to this group, send email to [email protected]. > To unsubscribe from this group, send email to > [email protected]<jallib%[email protected]> > . > For more options, visit this group at > http://groups.google.com/group/jallib?hl=en. > -- You received this message because you are subscribed to the Google Groups "jallib" group. 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