abcmann Posted January 21, 2009 Report Share Posted January 21, 2009 Hi, I found this today.....it looks really good for the most purposes. Better than a soundcard scope.http://jonw0224.tripod.com/ppmscope.htmlSpecifications and Goal Feature List:-------------------------------------------------- FeatureCurrent Version (v.2.01)Goal VersionSample RateVariable, single shot 1 MHz max, interlaced 151 kHz maxVariable, single shot max 1 MHz, interlaced max 417 kHz, repetitive 5 MHzBandwidth500 kHz500 kHzNumber of ChannelsTwoTwoSample Depth256 bytes per channel, 128 bytes per channel when interlaced256 bytes per channel, 128 bytes per channel when interlacedSample ModesSingle shot and interlacedSingle shot, interlaced channel, and repetitiveCalibrationVoltage offsetVoltage per division and voltage offset calibrationConfiguration SettingsConfiguration of default and saving of settings for future useConfiguration of default and saving of settings for future useHardware ConnectionAny parallel portAny parallel, serial, or USB portCouplingAC and DC, reflected on PCAC and DC, reflected on PCChannel gainGain of 1, 2, and 5, reflected on PCGain of 1, 2, and 5, reflected on PCTriggerVariable level, slope, and timingVariable level, slope, and timingFrequency SpectrumYesYesWaveform ReconstructionTriangle, square, point, and sincTriangle, square, point, and sincXY viewYesYesChannel offset and volt per division settingsYesYesCursorsYesYesMath functionsOnly addition and subtraction of channelsAddition, subtraction, auto period, auto peak-to-peak, etc.Waveform exportComma delimitedBitmap and comma delimitedI'll build one :Dbye Quote Link to comment Share on other sites More sharing options...
stryd_one Posted January 21, 2009 Report Share Posted January 21, 2009 Nice find. Much faster than this one: http://www.midibox.org/forum/index.php/topic,8218.0.htmlShame it's windows only :(Keep us posted on your build! Quote Link to comment Share on other sites More sharing options...
abcmann Posted January 22, 2009 Author Report Share Posted January 22, 2009 ill do that. i dont know if it helps, but there is the c sourcecode in the package. perhaps anybody can use it to run it under linux. Quote Link to comment Share on other sites More sharing options...
Max Romantschuk Posted January 22, 2009 Report Share Posted January 22, 2009 there is the c sourcecode in the package. perhaps anybody can use it to run it under linux.Unfortunately rather unlikely unless the code was written with portability in mind... But depending on how it interfaces with the hardware Wine might be an option. Quote Link to comment Share on other sites More sharing options...
Goblinz Posted January 22, 2009 Report Share Posted January 22, 2009 I wonder if that power supply scheme could be useful for other midibox hardware that requires +12 /-12 V ???? Do we have the numbers to get some PCB's made up? Quote Link to comment Share on other sites More sharing options...
philetaylor Posted January 22, 2009 Report Share Posted January 22, 2009 Do we have the numbers to get some PCB's made up?If a PCB manufacture is planned then i'm in!I'm sick of my crappy Velleman handheld scope......Phil Quote Link to comment Share on other sites More sharing options...
diablojoy Posted January 22, 2009 Report Share Posted January 22, 2009 would also be very interested in this I do need a scopevery soon Quote Link to comment Share on other sites More sharing options...
stryd_one Posted January 22, 2009 Report Share Posted January 22, 2009 ill do that. i dont know if it helps, but there is the c sourcecode in the package. perhaps anybody can use it to run it under linux.I didn't actually check the code but the comments said that he had decided to use Window API GUI controls, so porting it may not be so simple (possible though) Quote Link to comment Share on other sites More sharing options...
Goblinz Posted January 22, 2009 Report Share Posted January 22, 2009 If a PCB manufacture is planned then i'm in!I'm sick of my crappy Velleman handheld scope......PhilI may be getting a vocoder board fabbed at somepoint this year so think I'll add a scope board in at the same time if there's room so I can see it working.People should be aware that they'll need to use mains voltage to feed the transformer, something that I'm a little bit wary of myself.Another point is that the listed BOm comes to $110 + the cost of the board and encloure... A second hand scope could be bought of ebay for less than this. Quote Link to comment Share on other sites More sharing options...
Jack Posted January 22, 2009 Report Share Posted January 22, 2009 Hi!Before you pay over 100€, please check this for less money:main: http://www.fpga4fun.com/Hands-on_Flashy.htmlusb: http://www.fpga4fun.com/Hands-on_Flashy_USB.htmlshop: http://www.knjn.com/?pg=info&src=FlashyBest RegardsJack Quote Link to comment Share on other sites More sharing options...
Goblinz Posted January 22, 2009 Report Share Posted January 22, 2009 A simple digital oscilloscope recipeUsing parts from KNJN.com, here are the basic items of our recipe. * 1 x Pluto FPGA board, with TXDI and cable (item#1121 = $41.95) * 1 x Flash acquisition board (item#1205 = $39.95) * BNC connector + Male/female connectors 2x8 + Nylon standoffs/screws (item#1250 + #1275 + #1270 = $10.85)That's about $92.75 so far. Not much difference.The one mentioned earlier can be used as a function generator and as a power supply too. Quote Link to comment Share on other sites More sharing options...
MRE Posted January 22, 2009 Report Share Posted January 22, 2009 Look over the FPGA4FUN project again. It is essentially pre-built for one thing. (Two built modules connected together.. 5 minutes to make this thing, another 5 to download the fpga software to the board).For another, and this is the most important part: 100MHz vs 1MHz. To be honest, that 100Mhz might actually be 50 if you want any accuracy. Nyquest says you need at least 2 or 3 samples to per cycle before you can trust it. So I would take anything over 33Mhz with a grain of salt. That is still WAY better than 1Mhz.To spend more than $20 dollars on something in the 1-5 Mhz range is silly.(Hand-held semi pro 5Mhz+ scope-on-the-go gear is excluded ;)If I were choosing between the two, Id spend the bucks, forgo the time and (marginal) troubles of building the kit, and enjoy the higher freqs of the FPGA4Fun project.It also looks like a two channel version is possible with a bit more work (and some cash).As well as the option for LCD output.Finally, function generators are not that hard to get, or build when you really need one on the cheap.I would assume everyone here would back me up on this:When it comes to o-scopes... speed speed speed.My handheld 5mhz unit isn't bad. 5Mhz is good enough for most basic bench work. Its portable and not tied to a laptop. And it runs on batteries for hours. The problem with it is that, while it can sample up to 5Mhz, the screen refresh is more like 1Hz. That makes it impossible to use on all but the most stable and repetitive signals.FPGAs are MUCH faster than a PIC for something like this. They were designed to be the digital signal taskmasters for the analog world. FPGAs eat, drink and break signal processing. Go with it, forget the PIC. (although, if you really need that function gen, there are HUNDREDS of cheap projects for 1MHZ and lower signal generators for PIC.) Quote Link to comment Share on other sites More sharing options...
MRE Posted January 22, 2009 Report Share Posted January 22, 2009 It should be added that regardless of which project you choose, you will need to add significant signal conditioning and ranging circuits if you want to work with anything outside of 'digital' (0 to 5 volt) ranges.The front end signal conditioner from the first project is a good start. With some mods it could be attached to the FPGA4Fun design. Id still want to add a range circuit in front of that, before connecting to the probe, in order to protect all the expensive electronic circuitry. Quote Link to comment Share on other sites More sharing options...
JMS Posted January 22, 2009 Report Share Posted January 22, 2009 FUNCTION GENERATOR: (and other DIY nifty projects)http://www.nuxie1.com/guides/fungen-v2-kit.htmli started building this a while back, i even have the g-code to cnc out a board backed up somewhere. i cncd out a prototype board, drilled all the holse, soldered in the socket for the xr2206. i ordered some xr2206 samples... i never did much with the rest of the project except look at it sitting on my bench half done. i think it would be a DOPE! sound generator if attached to the midibox and a small app written, which could display the the waveforms maybe even?here is a link to the post with a video of the code being tested on my mini mill and a pic or two... http://ohiopctech.com/dp/?q=node/136(sorta) OFFTOPIC: just got my mbhp_core running with an lcd today, ready message on the lcd about an hour ago! so i'll be building some kinda function generator soon to be interfaced with this core. (and teaching myself asm in the process so i can try to code the app for it.) Quote Link to comment Share on other sites More sharing options...
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