#qi-hardware IRC log for Saturday, 2014-08-23

DocScrutinizer05wpwrak: tale care, that's how allergies are triggered10:40
DocScrutinizer05take*10:40
wpwrakoh, i've had that pollen allergy for a good while already. just not in this mix so far. one of the less welcome effects of global warming, i guess.12:45
wpwrakand if i was a klingon, i'd be happy with how this day started: killed two mosquitos even before my first cup of blood wine ;-)12:46
DocScrutinizer05fsck mosquitos. They almost ate me in holidays13:24
DocScrutinizer05exposure to allergens while your immune system fights bacteria or virus *can* trigger an allergy. actually it's one of the most common ways how allergies are triggered, it seems13:26
DocScrutinizer05otoh while you're exposed to a heavy ammount of allergens you're sensitized to, your imune system pays less attention to flu and other germs13:27
DocScrutinizer05and actually suppression of the allergic reactions is crucial to allowing your immune system to "forget" the allergy over the years13:29
whitequarkI think it's not "forgetting"13:29
whitequarkit's just shifting immune response to the one which is not annoying13:29
DocScrutinizer05it's "forgetting" like you lose immunity to a disease you suffered13:30
whitequarkIgE->IgG or something like that13:30
whitequarkmaybe more than one mechanism13:30
DocScrutinizer05well, yes that might be details I'm not knowing of. Sure the immune system still might counteract the allergen, but on a level that doesn't make you suffer ill effects13:31
DocScrutinizer05much of all this is about histamine release13:31
whitequarkI've also was curious about how they "desensitize" you by repeated exposure to allergen13:32
whitequarkand turns out it's not actually desensitization, just making sure a different type of response occurs.13:32
DocScrutinizer05guess why they call the antiallergica also anti-histaminica13:32
DocScrutinizer05:nod:13:32
DocScrutinizer05immune system is incredibly complex machinery13:33
DocScrutinizer05and eats amazing amounts of energy from your daily nutrition13:33
whitequarkI'm astonished it works at all13:33
DocScrutinizer05indeed13:34
whitequarkthe thing it does with DNA is mind-boggling13:34
whitequarkbrute-forcing protein configurations to find a proper antigen, basically13:34
DocScrutinizer05hehe13:34
DocScrutinizer05they fight cancer this way now13:34
whitequarkantibody*. like a massively parallel computer, except it doesn't compute, it tests it against the antigen right away13:34
DocScrutinizer05teach immune system to attack the cancer cells13:35
DocScrutinizer05by sensitizing them on a particular property of the cancer cells13:35
whitequarkyeah13:36
DocScrutinizer05not yet commonly used since it's "customized medication" which is extremely expensive13:37
whitequarkand because cancer is alive in first place because there's few things for immune system to grab onto...13:38
DocScrutinizer05that's the trick, the scientist helps the immune system by giving some "hint"13:38
whitequarkyeah I know, it's just that it doesn't work on "all" cancer13:39
DocScrutinizer05yeah, prolly not13:39
whitequarkyou're lucky if it works on yours13:39
DocScrutinizer05another thing they try is a virus that only "works" on the cancer cell DNA13:40
DocScrutinizer05quite ambitioned13:40
DocScrutinizer05ambitious*13:41
DocScrutinizer05and if the virus doesn't already kill the cancer cells, it might at least "tag" them for immune system to spot and attack them13:42
DocScrutinizer05the immune system's "problem" is: it can only see the cell hull and the proteins on there. It can't know about the DNA inside13:43
whitequarkyes. you don't have to tell me, I almost graduated in bioengineering ;p13:44
DocScrutinizer05:-)  Not teaching you, I thought some others might be interested readers13:44
Action: whitequark looks around13:45
whitequark*crickets* *tumbleweed*13:45
Action: DocScrutinizer05 looks in wpwrak's direction13:45
DocScrutinizer05also I'm happy to check my pretty annoying half-knowledge against somebody who really understands that stuff13:46
DocScrutinizer05NB I not even considered graduating in biology or chemistry13:46
whitequarkI definitely wouldn't pitch myself as an expert in the area13:46
whitequarkbut I know some basics13:46
DocScrutinizer05prolly more than I do13:47
DocScrutinizer05e.g. the antibody shaping is sth I once maybe heard about but for sure wasn't in my active knowledge vault13:48
whitequarkthat's in 2nd year curriculum today, but I think it is pretty recent research13:49
DocScrutinizer05that's special detail knowledge I find very intriguing but alas had no time to look into as much as I would like to13:49
DocScrutinizer05and the semi-popular-science reports I usually listen to or read are not dealing with this kind of detail13:50
whitequarkDocScrutinizer05: https://en.wikipedia.org/wiki/Antibody#V.28D.29J_recombination13:50
DocScrutinizer05ta13:50
whitequarkthis is a pretty good overview13:50
DocScrutinizer05:-D13:50
whitequarkhttps://en.wikipedia.org/wiki/V(D)J_recombination even13:50
DocScrutinizer05much appreciated13:50
whitequark1987. how the hell do you discover such an enormously complex mechanism even without good computers?!13:51
whitequarkoh, I see, he sequenced a lot of DNA and observed the recombination directly13:52
DocScrutinizer05wow13:52
DocScrutinizer05I also only know cloudy factoid fractions about that two-stage sensitizing to allergens13:53
whitequarkthe general idea is that first you have the antigen presented to your immune system, and it doesn't cause any reaction, but makes it memorize the antigen13:54
DocScrutinizer05first stage: get exposed but do not suffer from ill effects. Just "lern to know" the allergen. 2nd stage: on a second exposure to same allergen the immune system actually starts taking action13:54
whitequarkand then at some random point in future boom! you get anaphylactic shock13:54
whitequarkyeah.13:54
whitequarkcorrect13:54
DocScrutinizer05I just have *no* idea *why*13:55
DocScrutinizer05hand-over from one cell type (T-cells?) to another ?13:55
DocScrutinizer05I used to know this, but have forgotten the details13:56
whitequarkyes13:56
whitequarkYour body produces IgE designed specifically for that particular allergen, but you won't experience a reaction yet.13:56
whitequarkIf you are atopic (meaning, youve inherited a predisposition toward allergic disease), your T cells are quick to stimulate B cells13:56
DocScrutinizer05IOW I once watched a report that explained it. But only one report13:56
whitequarkWhen stimulated, B cells develop into plasma cells13:56
whitequarkPlasma cells produce IgE antibodies, which are targeted to that specific allergen13:56
whitequarkThe IgE binds to special receptors on mast cells13:56
whitequarkYour system is now sensitized. Your mast cells are like little bombs that are armed and ready for detonation.13:56
whitequarkhttp://www.nature.com/nm/journal/v18/n5/fig_tab/nm.2755_F1.html haha, nice diagram13:57
DocScrutinizer05wow, amazingly complex and intriguing, this stuff (not diagram, pending to watch it)13:58
whitequarkand also: "The mechanisms of primary sensitization are still essentially unknown."13:58
DocScrutinizer05haha13:58
DocScrutinizer05that makes me feel a little better about not completely knowing the facts ;-)13:59
whitequarkthere's quitea  bunch of things in biology that we surprisingly still don't know13:59
whitequarkso for example in 2014, we still have basically no idea how anaesthesia works13:59
whitequarklike, at all. there is a bunch of theories which may or may not be correct14:00
whitequarkgeneral anaesthesia, that is14:00
DocScrutinizer05the occasional reader might think we're vastly off topic here and now. But it's all just about ``<wpwrak> been near-dead for well over a month last year, when that mixture struck the first time.´´ which we for sure must fight so it won't happen again ;-)14:01
whitequarkthe leading theory is that it is basically throws a wrench into pretty much ALL proteins14:01
whitequarkthough to a different degree14:01
whitequarkin which case I don't know why anyone comes through it alive at all14:01
DocScrutinizer05yup14:02
DocScrutinizer05and only recently they noticed the increased danger of old patients suffering a non-reversible disorientation from anaesthesia14:03
whitequarkhm, was it? I thought GA was always thought to be one of the procedures that if you can avoid, you do...14:03
DocScrutinizer05and of course they have NFC why that happens and what to do against it14:03
whitequarkcompletely unrelated, have you seen sigrok?14:04
DocScrutinizer05what's that?14:04
whitequarkI'm having a lot of fun playing with it and probably end up contributing14:04
DocScrutinizer05sth like seti?14:04
whitequarka FOSS toolchain for logic analyzers, but also scopes, meters, and all kinds of digital and analog data acquisition devices14:05
DocScrutinizer05seti@home14:05
DocScrutinizer05oooh14:05
whitequarkthey have a nice GUI that you would actually want to use14:05
whitequarkthough rough on edges14:05
whitequarkand a LOT of supported devices14:05
DocScrutinizer05FOSS sounds like linux version available14:05
whitequarksure14:05
DocScrutinizer05so basically a signal analyzer?14:06
whitequarka PC software for logic analyzers.14:06
whitequarkand it has FOSS firmware for some of the supported hardware as well, but it's secondary.14:06
whitequarkyou can stack decoders in it14:06
whitequarklike this: https://i.imgur.com/f5kAMCf.png14:07
DocScrutinizer05that sounds like it's a FOSS version of that multi-k$ software that comes with the *good* scopes14:07
whitequarkso you can for example tell it to decode I2C then decode a particular I2C protocol and display14:07
DocScrutinizer05COOOOOOL14:07
whitequarkor even decode an EEPROM write log and give you a firmware that you can flash14:07
DocScrutinizer05exactly what I referred to one above14:07
whitequarkyes14:08
whitequarkI just added support for some chinese analyzer I bought for $35: http://sigrok.org/wiki/Mcupro_Saleae1614:08
whitequark100MS/s, 16 channels14:08
DocScrutinizer05\o/14:08
whitequark(not at same time... 100MS/s for 3 channels.  12MS/s for all 16)14:08
sb0whitequark, so sigrok doesn't suck anymore? I tried analyzers in 2011 and the outcome was that the proprietary saelae was the least bad14:09
whitequarksb0: it is absolutely usable14:09
whitequarkyou will get some papercuts but it can be used for real work.14:09
whitequark(like triggers not working from GUI right now, you'll need to use sigrok-cli if you want triggers. etc.)14:10
sb0even installing (=compiling) it was a mess, it was split among different packages, with lots of version incompatibilites14:10
whitequarkstill four packages, but build process is ./configure && make14:10
whitequarkor install it from debian14:10
whitequarkapt-get install sigrok14:10
Action: DocScrutinizer05 ebays for that critter14:10
whitequarkDocScrutinizer05: http://www.aliexpress.com/store/product/USB-Logic-Analyzer-100M-max-sample-rate-16Channels-10B-samples-MCU-ARM-FPGA-debug-tool/614202_1916810169.html14:10
whitequarkit's even $29 now. a bargain14:11
whitequarkDocScrutinizer05: a hw dev I know, upon hearing cost, said "wooow... I can now just sample all my test points at once with a bunch of these"14:11
DocScrutinizer05or maybe I should check out a few of combined scope/logic-analyzer devices supported, and finally do what wpwrak tried to convince me: get a scope14:12
whitequarkbuy a bag of those, plug into four separate root USB ports, profit!14:12
whitequarka 64-channel logic analyzer14:12
whitequarkfor uh $12014:12
DocScrutinizer05indeed, I guess I will do so. Instantly14:12
whitequarkyou still need to sync them but it is not a major problem14:12
DocScrutinizer05hey, sounds like a nice weekend project14:13
DocScrutinizer05(sync)14:13
whitequarkyes. I would just use something that generates e.g. gray encoded sequence of 0000 0001 0010 ...14:13
DocScrutinizer05how about cheap&silly: feed a 100MHz master clock to one input of each device?14:14
whitequarkand then write a simple script that adjusts the delays14:14
whitequarkwell, with plain 100MHz master clock you have the problem that any two cycles look alike14:14
whitequarkso if you have more than 10ns of drift, you'll end up in desync14:14
DocScrutinizer05yeah, we can cure that14:14
DocScrutinizer05:-)14:14
whitequark(also, it's only 16MS/s at all 16 channels)14:14
DocScrutinizer05wobble the master clock a bit14:14
whitequarkyeah, that's basically the idea14:14
DocScrutinizer05yup14:14
whitequarkoh by the way, see how the vendor logo is censored on aliexpress?14:15
DocScrutinizer05hehe14:15
whitequarkthat's because it is literally named the same as an existing company and product: https://www.saleae.com/logic1614:15
whitequarkand it has "compatible" firmware14:15
whitequarktruly shameless14:15
sb0"Support  all version of   Original software"14:17
DocScrutinizer05wait, that thing comes with 10Gsamples buffer?14:17
whitequarkDocScrutinizer05: no, it streams samples live to the PC14:17
whitequarkno memory at all onboard14:17
DocScrutinizer05duh14:17
whitequarkso buffer is only limited by your RAM14:18
DocScrutinizer05>>2.Billions of samples14:18
DocScrutinizer05can save as many as 10B samples, letting you capture even the most elusive events. No more dealing with frustratingly small sample buffers<<14:18
whitequarkand sigrok RLE-compresses the samples14:18
whitequarkso in practice it is almost unlimited14:18
whitequarknote though that you won't get 100MS/s if something else is on that USB bus14:18
DocScrutinizer05yeah, no practical issue, just a puzzling marketing-gibberish14:18
whitequarkI stumbled into that problem14:19
whitequarkany other transaction on bus makes a buffer overrun and it stops14:19
DocScrutinizer05ooomph14:19
whitequarkso you need dedicate USB for it. could prolly go with PCI USB14:19
DocScrutinizer05sure thing14:19
whitequarkPCI-e14:19
whitequark50MS/s is fine though14:20
DocScrutinizer05that too, prolly14:20
DocScrutinizer05what's the input signal conditioning like?14:20
whitequarkwhatcha mean?14:20
DocScrutinizer05levels, OVP, etc14:21
whitequarkoh14:21
whitequark1.5V14:21
whitequarkOVP... no clue, need to reverse-engineer the board14:21
DocScrutinizer05:-P14:21
whitequarkit didn't come with even a CD or a paper manual14:21
whitequarkjust the device and two cables14:21
DocScrutinizer05too expensive ;-)14:21
whitequarkhardcore chinese cost reduction14:21
DocScrutinizer05yup14:21
whitequarkthe USB cable they have is *good* though14:21
DocScrutinizer05LOL14:21
whitequarkI tried several mine and the LA will just not enumerate or fail to work14:22
DocScrutinizer05duh!14:22
whitequarkwith theirs -- thick, heavily shielded cable -- it works perfectly14:22
whitequarkand a huge choke too14:22
DocScrutinizer05hm, ok, that means their PHY sucks14:22
whitequarkmore like I had really shitty cables14:22
DocScrutinizer05or that14:22
whitequarkPHY is standard Cypress FX2LP14:22
whitequarkthey're like in all test equipment made in last decade14:22
DocScrutinizer05no experience with that one14:22
DocScrutinizer05ok14:23
DocScrutinizer05should 'just work' then14:23
whitequark8051 core with deeply integrated USB14:23
DocScrutinizer05:nod:14:23
whitequarkand it can download firmware from host by itself, so no need for EEPROM14:23
DocScrutinizer05cool14:23
whitequarkwell, for big EEPROM. it still has one for ID & so14:23
DocScrutinizer05yeah14:23
whitequarkit's usually used as an interface converter between USB and FPGA14:24
whitequarkit has a 16-bit bus that you just route to your FPGA14:24
whitequarkSPI too, for firmware upload14:24
DocScrutinizer05actually I'm 'used to' the 8051, my last hw design I did commercially on small scale used a atmel 89cxx5114:24
whitequarkyeah 8051 is not the worst core there is14:25
whitequarkcould be PIC...14:25
DocScrutinizer05and almost 40 years old, so really widespread and common14:25
whitequarkthere's still no non-shitty C compiler for 8051 though14:25
whitequarkonly sdcc14:25
DocScrutinizer05hmm14:26
whitequarkand sdcc is ... meh. it works, but meh14:26
DocScrutinizer05I used assembler iirc14:26
DocScrutinizer05http://maemo.cloud-7.de/dscf3349.jpg14:27
whitequarkoh that thing14:28
DocScrutinizer05pusteflipper, yeah14:28
DocScrutinizer05(plus a few other projects I realized based on this design)14:29
whitequarkhmm, what did it do again?14:30
DocScrutinizer05like translucent tiles with a 16 red LEDs behind, which you could daisychain with a 3wire connection to form moving light patterns of arbitrary length14:30
whitequarkoh right, LEDs14:31
DocScrutinizer05pusteflipper itself was a pinball alike medical tool, for ergotherapy14:31
DocScrutinizer05http://www.mausklick-produktion.de/14:32
DocScrutinizer05http://wstaw.org/m/2014/08/23/plasma-desktopD24150.png is a ramp&target-hole which, when blowing the pingpong ball into it had a mouse look out of the hole for a second14:35
DocScrutinizer05like a coo-coo clock14:35
DocScrutinizer05http://wstaw.org/m/2014/08/23/plasma-desktopS24150.png is a "volcano" - when you make the ball fall into it, it "erupted" (a set of 6 red-orange LEDs in the plexi volcano started flashing, resembling a bit on lava running down the side of the volcano)14:38
wpwrak(fight for my health) thanks ;-)14:39
DocScrutinizer05all those targets had IR light barriers, formet of only a IR LED and photodiode connected to the small circuit of http://maemo.cloud-7.de/dscf3349.jpg14:39
DocScrutinizer05formed*14:40
wpwrak(LA) and only closed-source host sw, it seems14:40
DocScrutinizer05the whole thing ran for hours from a single 9V block14:40
DocScrutinizer05the cermet trimmer is for adjusting battery voltage threshold when battery-empty signalling kicks in14:42
DocScrutinizer05I took incredibly "chinese" "optimizations" on BOM of that thing14:42
DocScrutinizer05e.g. the LEDs where GPIO to GND, without any series R. The resistor onside the 89c2051 would do, as long as not more than one LED got operated simultaneously (in which case the total power dissipation of the chip would get exceeded)14:44
whitequarkwpwrak: um, what?14:46
whitequarksigrok is specifically open-source host sw14:46
DocScrutinizer05[2014-08-23 Sat 16:01:06] <DocScrutinizer05> the occasional reader might think we're vastly off topic here and now. But it's all just about ``<wpwrak> been near-dead for well over a month last year, when that mixture struck the first time.´´ which we for sure must fight so it won't happen again ;-)14:46
whitequarkthere are open-source firmwares for some of the simpler devices14:46
DocScrutinizer05ooh14:47
whitequarklike you can build one yourself out of Cypress CY7C68013A, an xtal and some resistors14:48
whitequarkand have a good 12MHz 8-channel logic analyzer14:48
DocScrutinizer05I'm looking at http://www.aliexpress.com/store/product/Free-Shipping-Sysclk-DX-Mixed-Signal-Oscilloscope-and-logic-analyzer-USB-2-probe-P6100-20LA-probes/614202_583945355.html ATM14:57
wpwrakwhitequark: i was referring to that selig thing. but maybe you're already talking about something else14:58
whitequarkselig?15:04
whitequarkwth is selig?15:05
whitequarkDocScrutinizer05: OOOH sysclk15:05
DocScrutinizer05hm?15:05
whitequarkiirc someone mentioned that sysclk was done by a dude from china (mcupro) which also done the design of my LA15:06
whitequarkand mcupro is someone with topnotch EE skills15:06
whitequarkI need to ask tho15:07
whitequarkhttp://www.eevblog.com/forum/testgear/sysclk-dx-logic-analyser-mso/15:08
whitequarksee the CY7C68013A? :)15:08
whitequarktold you, they're everywhere15:08
whitequarkDocScrutinizer05: however analog sample rate of 24MSps15:10
whitequarkdo you really need that?15:10
whitequark3MHz bandwidth15:11
whitequarkhttp://sigrok.org/wiki/File:Sysclk_lwla2034_pcb_top.jpg lol15:13
whitequark(not your device)15:13
whitequarkseems like a variant of this: http://sigrok.org/wiki/Sysclk_AX-Pro15:14
whitequarkor maybe not, just mildly similar15:19
whitequarkDocScrutinizer05: in any way, the device you linked to is not supported by sigrok15:19
DocScrutinizer05oooh15:19
whitequarkDocScrutinizer05: http://sigrok.org/wiki/Supported_hardware15:19
whitequarkmost of it has ebay/aliexpress/taobao links15:20
DocScrutinizer05GPIB interfaces - lol15:24
DocScrutinizer05agilent or rigol, that's the question. Or even a fluke multimeter?15:25
wpwrak(selig) err, sorry, saleae15:25
DocScrutinizer05scopemeter15:25
wpwrakDocScrutinizer05: fluke are $$$. agilent also tend to be overpriced. rigol and siglent seem to be good choices. depends on what features you want.15:27
DocScrutinizer05I know wluke are made of gld, or even platinum15:27
DocScrutinizer05fluke*15:27
DocScrutinizer05>>The Fluke ScopeMeter test tool is the one tool you can rely on to tackle just about any troubleshooting task.<<15:28
wpwrakif you're shopping for a multimeter, then i'd go for fluke. they make the only one i found so far that can measure current halfway decently. all the others crap out if you go to single-digit uA or have a massive burden voltage. and yes, this includes agilent.15:28
wpwrakif all you want to measure are volts, when most will work, though ;-)15:29
wpwrakso .. scopes. your choices would be: low-end: Rigol DS1000Z series. up to 4 channels, now also available as MSO. there have a lot of overpriced options but you can hack the scope to enable them.15:30
wpwrakmedium range: Siglent SDS2000 series. also available as MSO. better features than the rigol and much less of a "free to play (but pay to win)" concept15:31
wpwrak(and the few options that may be interesting for the siglent are reasonably priced)15:32
wpwrakif you only want two analog channels, you could also consider the rigol DS2000A (or a 2 channel version of siglent SDS2000). the siglent is better but the rigol a bit more mature.15:33
wpwrakhigh-end: too expensive for mere mortals like us ;-)15:33
wpwraki find MSO not extremely useful. SPI tend to be about the worst you'll ever encounter, and that has 4 signals. and if you want to compare with some other signal, you typically only need 1-3 from SPI, plus the other.15:35
wpwrakso i'd rather go for 4 analog channels than 2 analog + MSO. if i wanted to throw a lot of money at it, then i may consider adding MSO after i get 4 analog channels.15:36
DocScrutinizer05fluke 190-502: ~ 4..5 k15:37
DocScrutinizer05:-S15:37
wpwraksince your spanish must now be quite good, here are the siglent sds2000: http://www.temtecsa.com.ar/index.php?cPath=21_9315:37
wpwrakand this is the rigol DS1000Z series: http://www.temtecsa.com.ar/index.php?cPath=21_9515:37
DocScrutinizer05bwahahaha, please don't ask me to understand a single word of spanish15:37
wpwrakas i said, you can hack the rigol for example to upgrade from 70 MHz to 100 MHz.15:38
wpwrakthat site has a nice overview. at other places you often get some messy list that is painful to navigate. and you can probably guess all the technical terms anyway ;-)15:39
DocScrutinizer05it always kills me to tell "X bandwidth is what I will be happy with"15:44
DocScrutinizer05figure I go for a 100MHz scope and it turns out I need 15015:44
wpwraknaw, it's usually "X bandwidth is what i can afford" :)15:44
Action: DocScrutinizer05 needs coffee15:45
wpwrak100 is a decent choice. if you can go a little higher, even better. i rarely run into things i can't handle at 100 MHz.15:45
wpwrakand for things like power supply issues and such, 100 MHz is plenty15:45
DocScrutinizer05I'd guess I maybe run into other more practical problems when going for >100MHz, like mere technical interfacing to signal etc15:46
wpwrakyes, that becomes a problem quickly :)15:46
DocScrutinizer05actually PSU is a *very* good benchmark. I need to check what frequencies we might face in those switched critters, at maximum15:47
DocScrutinizer05from my arse I'd pull a 40MHz figure15:47
wpwrakso 100-200 MHz.15:47
DocScrutinizer05:nod:15:47
DocScrutinizer05for USB I'd need >500MHz, that's insane15:49
DocScrutinizer05if I'd go for USB, I'd already want 800MHz (firewire etc) too15:51
DocScrutinizer05so 1GHz15:51
DocScrutinizer05I guess 100MHz 4 chan is a fine choice15:51
wpwraki'd consider USB HS inaccessible15:51
DocScrutinizer05:nod:15:51
DocScrutinizer05or 2 chan plus parallel LA15:52
DocScrutinizer05you never need more than 2 chan analog analysis15:52
wpwrakif you go with rigol, then yes. if you pick siglent, there's a difference of about USD between 100 and 200 MHz. (the argentine prices, with customs fees but without taxes, are a bit inflated, so they should correspond roughly to EU with all taxes and fees)15:53
wpwraki'd want to be sure that what he LA thinks it sees it really what's happening15:53
DocScrutinizer05you got 2 fine analog channels to make sure15:54
DocScrutinizer05one for the signal under test, and one to probe the LA input on parallel with the scope, to make a swift inspection about what the signal really looks like. after that all you want is digital input and storage for all but the one signal under test15:55
wpwrakmmh, i hate fiddling with the LA until it actually shows the correct signal15:56
wpwrakmuch easier to just get the analog one and work on that15:56
wpwrak(of course, my DS1102CD also has a crappy LA, making things a lot more difficult)15:57
DocScrutinizer05yeah, you most likely want a signal conditioner in front of your LA inputs15:58
DocScrutinizer05sth nice that offers adjustible threshold levels and hysteresis. Prolly built from analog components15:58
DocScrutinizer05maybe even adjustable LPF15:59
DocScrutinizer05so, sth like 3 potis and a 2 or 3 opamps per input16:00
DocScrutinizer05DAMN, I wonder which poltergeist has cursed my home while I was away. 3..4 devices of my homematic the batts went low (supposed to last a year at least, so how high are the odds 4 are going low batt in 2 weeks?), plus some fire alarm triggered, and a lot of connection-lost/data-error reports16:02
DocScrutinizer05scary16:03
wpwrakmaybe have a second look at these things that you don't remember to have been black ? :)16:03
DocScrutinizer05the receivers of those critters work intermittent. I wonder if their firmwate fails to ever shut down the RX when a continuous stream of illegible garbage comes in16:04
DocScrutinizer05none turned black16:04
DocScrutinizer05at least none found so far16:05
DocScrutinizer05the fire alarm went off 10 days into my holiday16:05
DocScrutinizer05the damn shit doesn't record which of the sensors triggered :-(16:06
DocScrutinizer05idiocy16:06
DocScrutinizer05it's a "alarm group"16:06
wpwrakmaybe "post mortem analysis" wasn't very high on their list of design goals ;-)16:07
DocScrutinizer05I wonder if I should unpair the 3 sensors and form 3 individual alarm groups out of them. This however would defeat the one reason why they are RF alarms anyway: in-sync alarm on all sensors when some emergency happens16:08
DocScrutinizer05of course you cannot trigger alarm remotely on the smoke sensors, except by another sensor going tripped16:10
DocScrutinizer05there's a reason for all that: they want to sell their $$$ fire alarm central16:10
DocScrutinizer05insane16:10
DocScrutinizer05same shit with heater valve actors: you cannot control them from HM-CCU1, you need a thermostat to send commands to them16:14
DocScrutinizer05CCU has linux on it, I ponder since months to force eq3 to disclose the complete sourcecode16:15
DocScrutinizer05I'm absolutely sure on a low level I *could* send commands to the valve actors directly from CCU transceiver16:17
DocScrutinizer05I mean, CCU syslog is recording the full communication between thermostat and valve actor16:18
DocScrutinizer05and if my last PC OS upgrade hadn't nuked all that and I've been too lazy to re-install and configure all of that crap, the syslog on PC for homematic had logs about which smoke detector sensor triggered the alarm16:20
DocScrutinizer05but that really sucks to do 2 full manweeks of /etc/bla/* edits and stuff after every system upgrade. I don't get it how the windows guys can happily re-install their crap every 4 weeks, to clean up registry and whatnot16:22
DocScrutinizer05you prolly only can do this when you use even mail only via web frontend16:23
DocScrutinizer05I dunno, should I create one monster script to do all customization of the system via sed and similar stuff?16:25
DocScrutinizer05mmmpfff, it been the crappy CCU which forgot the IP of my pc:514 during last firmware update. GREAT!16:33
DocScrutinizer05homematic, my ass16:33
DocScrutinizer05(valve actor) like http://privatepaste.com/72872775c516:55
DocScrutinizer051st is thermostat, 2nd is valve actor ack to thermostat16:56
DocScrutinizer05whitequark: Putin's revenge? The russian rocket parked Europe's first two Galileo sats in a 5000km too low orbit18:11
DocScrutinizer05on other topic: is there a rsyslog configurator tool for dummies? I have a damn hard time reading that gibberish manpages to figure which friggin facility etc I want to filter on18:13
DocScrutinizer05could it be that facility (local0 .. local7 or whatever) isn't printed at all to the var/log/messages file?18:14
DocScrutinizer05IOW, can somebody please give me a clue how to filter on that stuff: http://privatepaste.com/72872775c518:16
DocScrutinizer05I don't want the homematic remote logs in my local PC's syslog file, they should go to their own file18:17
DocScrutinizer05first token is timestamp, 2nd token is system hostname18:18
DocScrutinizer05I prolly want to filter on 2nd18:18
DocScrutinizer05man rsyslog.conf  drives me nuts18:19
Action: DocScrutinizer05 starts puking when in a manpage text shows up that says stuff like:18:25
DocScrutinizer05   Expression-Based Filters18:25
DocScrutinizer05       See the html documentation for this feature.18:25
DocScrutinizer05MEH!18:42
DocScrutinizer05man rsyslog.conf|less '+/Please  note  that  templates  can also.*|hosts to different files.*|This template can.*"'18:42
wpwrak(galileo) putin seems unlikely. why would he make his rockets look bad ? they're good business. besides, it wasn't the soyus rocket themselves but the upper stage, sort of a range extender. here's a good comment: http://www.heise.de/newsticker/foren/S-Technische-Details/forum-284470/msg-25688064/read/19:14
DocScrutinizer05damn that crap. what means a minus in front of /var/log/blah ?19:14
DocScrutinizer05in rsyslog.conf19:14
wpwraka much more plausible explanation would be insurance fraud. after all, these things are insured. and i wonder if anyone actually still believes galileo will ever work19:15
DocScrutinizer05why not?19:19
DocScrutinizer05thanks for the link btw19:19
wpwrakthey're something like 10 years behind schedule, their old test satellites are failing at 1/4 of their design life, ...19:19
wpwrakwith EU projects, there's always a high risk that they're just hidden "donations" to certain companies19:20
wpwrakhappens elsewhere too, of course19:21
DocScrutinizer05on a sidenote I find it quite funny how everybody is using https:/ for quite about everything - starting with heartbleed19:21
DocScrutinizer05maybe actually a good strategy to flood the ssl bug thing with irrelevant data19:22
wpwrak;-)19:23
DocScrutinizer05maybe even use http for the security relevant stuff like logins etc then19:24
DocScrutinizer05weird: your link to heise wasn't https19:24
DocScrutinizer05prolly again a embedded ad that was on https, I hate that19:25
DocScrutinizer05and particularly the warning it creates when I click on any link on the original non-secure page19:25
DocScrutinizer05dafaq! can anybody tell me what the "-" means?19:45
DocScrutinizer05http://i44.photobucket.com/albums/f35/wolf_pro/Galileo%20Orbit/3d-2_z19:45
DocScrutinizer05ps053596a9.jpg~original19:45
DocScrutinizer05oops 19:45
DocScrutinizer05# email-messages19:45
DocScrutinizer05#19:45
DocScrutinizer05mail.*<><------><------><------><------>-/var/log/mail19:46
DocScrutinizer05mail.info<-----><------><------><------>-/var/log/mail.info19:46
DocScrutinizer05mail.warning<--><------><------><------>-/var/log/mail.warn19:46
DocScrutinizer05mail.err<------><------><------><------> /var/log/mail.err19:46
DocScrutinizer05(the "<><------>" are mc tabs)19:46
DocScrutinizer05damn19:47
DocScrutinizer05*.=warning;*.=err         -/var/log/warn19:48
DocScrutinizer05*.crit          /var/log/warn19:48
DocScrutinizer05whatever it means, it seems to work without as well19:55
DocScrutinizer05there are really manpages you can't help but hate them19:55
DocScrutinizer05wpwrak: still tempting: http://www.testequipmentdepot.com/fluke/scopemeter/190-104.htm20:17
DocScrutinizer051000V floating per channel20:17
DocScrutinizer05alas too expensive20:18
wpwrakgood. less risk of you suddenly feeling an irresistible desire to make a habit of actually touching something with 1 kV ;-)20:20
wpwrakalso, it has a crappy screen. you'll want a nice screen. big, if possible. vision only gets worse with age. i'm old enough to know that, too :)20:21
DocScrutinizer05yeah, see "Kaz911 - Tuesday, July 31st 2012" on http://www.myflukestore.com/p8358/fluke_190-104_s_with_software_and_hard_case.php20:28
DocScrutinizer05I'm really in love with the field-test design20:28
DocScrutinizer05but the bang-per-buck is poor for the fluke20:29
wpwrakDocScrutinizer05: look at the lovely screenshots at the bottom of http://www.tequipment.net/Siglent/SDS2104/Digital-Oscilloscopes/20:37
wpwrakthey're much safer ;-)20:37
wpwraknote the colored intensity grading. rigol also have intensity grading, but only monochrome20:38
DocScrutinizer05yeah, looks fine20:41
DocScrutinizer054ch/100 ?20:41
DocScrutinizer05IE SDS2104?20:43
DocScrutinizer05meh, not even listed on http://sigrok.org/wiki/Supported_hardware#Oscilloscopes20:59
wpwrakmaybe be a bit early. they're still quite new. and they're just about to release the "programming manual" (SCPI and such)21:12
wpwraknew means of course that people are doing some rather rigorous tests with them. so far they seem to be holding up rather nicely. eventually folks do find issues, but they're in pretty obscure areas.21:12
hozerinteresting21:18
hozerI have an Owon 7102V, seems like it's not supported yet.. but this is interesting .. http://jaanus.tech-thing.org/teardowns-and-reviews/owon-ds7102v-teardown-and-review/21:18
DocScrutinizer05wpwrak: seems to me like rigol is the more mature and thus better supported device though21:26
hozeranyone else heard of the Owon ? It seems to work as well as the Rigol scope I used and has a bigger screen and ethernet21:27
DocScrutinizer05never21:27
wpwrakDocScrutinizer05: yes, rigol is more established. but they don't have a good 4 chan "advanced" offer. the DS2000 series it limited to 2 channels and generally compares poorly with the SDS2000.21:28
DocScrutinizer05hmmm :-/21:28
wpwrakowon, hantek, etc. have a poor reputation. apparently numerous small flaws. so more the entry-level sort of scopes you'd get for arduino work ;-)21:29
wpwrakand i think the owon 7xxx is about of the same generation of the rigol ds1000z, so you shouldn't really compare it with the old ds1000c/cd/d/e21:30
wpwrakDocScrutinizer05: (rigol vs. siglent) e.g., the sample rate of the ds1000z isn't very good if you use all four channels. the ds2000 and sds2000 maintain much higher sample rates.21:32
DocScrutinizer05sure21:33
hozerAll I really want is a Lecroy analog input stage connected to an fpga I can program ;)21:33
wpwrak;-)21:33
DocScrutinizer05aiui ds2000 is rigol while sds2000 is siglent21:33
wpwrakhozer: it's good to avoid there rest of the lecroys, though, since their "brain" runs windows ;)21:33
wpwrakDocScrutinizer05: correct21:33
hozersuch braindamage ;)21:33
DocScrutinizer05damn confusing21:33
wpwrakDS* = rigol, SDS* = siglent21:33
DocScrutinizer05why do you compare rigol to rigol?21:34
DocScrutinizer05I didn't even consider ds100021:34
wpwrakdifferent classes of rigol. ds1000d/e = entry level. ds1000z = ambitious amateur. ds2000 = basic professional. and so on.21:34
wpwrakwell, it's always a question of the budget :)21:35
DocScrutinizer05it's a question between siglet and rigol for now, unless I go mad end get a agilent21:35
DocScrutinizer05or even get me a used scope21:36
DocScrutinizer05but used ones are only interesting on analog, and that's not what my future lab-rev2 will look like21:36
DocScrutinizer05I want everything connected with everything21:37
wpwrake.g., all i have is an "entry-level" ds1102cd. if it would fail completely (its communication subsystem got damaged a few months ago, but i can still use it), i'd aim for a ds10740z and hack it to 100 MHz since it would simply take too long to save for something better. if i had a pile of cash, i'd go for an sds2104 or 220421:37
DocScrutinizer05I need a scope that's 100% supported by remote control21:38
wpwrakyes, connectivity is important. that's something that gets a lot better with modern scopes. "used" (but high-end) often means shitty communication and tiny memory.21:38
DocScrutinizer05I can easily see I get fed up with the inconvenient UI21:38
wpwrakanything modern should be21:38
DocScrutinizer05that's why I consider a new one, not used one21:39
wpwraki think the ui is important. it's what i use 99% of the time. the 1% remote access are for "hard" problems.21:39
DocScrutinizer05I want e.g. macros21:39
DocScrutinizer05I just watched a rigol video explaining runt trigger. OMG!21:39
wpwrakbut there's also the undeniable convenience of being able to take a screenshot without fiddling with a usb stick. right now, that's all i can do, since comms are down :-(21:40
DocScrutinizer05instead of two turn buttons for upper and lower threshold they allow either changing upper, lower, or both in sync, with one turn button, and you need clumsy select between those modes via a menu21:41
wpwrakyeah, there are this sort of messy things. but you get used to them. you'll still hate them all your life, though21:41
DocScrutinizer05I can *easily* see a macro I want to have on my remote rigol GUI in PC, to do this in a different way21:42
wpwraki wish someone made a decent scope with open firmware. then one could simply fix the damn thing.21:42
wpwrakin the end it21:42
wpwrak'll be harder to use :)21:42
DocScrutinizer05indeed21:42
DocScrutinizer05huh?21:42
wpwrakmost scope use is interactive: you generate the signal and adjust the settings until you get what you want21:43
DocScrutinizer05yep, exactly21:43
wpwrakif you go my program, then your feedback loop gets a LOT slower21:43
wpwraks/my/by/21:43
DocScrutinizer05why?21:43
wpwrakinstead of turning a knob until it's "nice", you go from scope to pc, edit the settings there, load new settings, return to scope, etc.21:44
wpwrakor you make your own pseudo gui .. and miss the haptics of real knobs and such21:45
DocScrutinizer05what's wrong with a PC kbd in front of the cheesy rigol. with - dunno - lower threshold of runt trigger on F1/2 and upper on F3/4 ?21:45
DocScrutinizer05or, like you say, evebn use a game controller or whatever21:45
DocScrutinizer05with real turn buttons assigned to that stuff21:45
wpwrakyou could of course get, say, a midi control box with these critters and work that into the gui, but at some point you'll spend 100x more time on that "perfect" gui than you're saving on having better controls. it just doesn't scale in your favour.21:46
DocScrutinizer05saving on having better controls?21:46
DocScrutinizer05I'm saving my nerves in that. Invaluable21:46
wpwrak#s/on/by/ :)21:46
wpwrak;-)21:47
DocScrutinizer05heck, cheap midi boxen are abundance, and the janus app to translate that stuff into a macro sequence and send to a well documented comprehensive remote control interface on a scope is just a weekend's  works21:48
wpwrakfamous last works ;-)21:49
DocScrutinizer05what I do *not* want to have to do is replacing all turn buttons and pushbuttons in scope by ALPS motor driven stuff21:49
wpwrakanyway, i would expect either to have good "remote control"21:50
DocScrutinizer05now THAT qualifies for famous last words, regarding siglent21:50
DocScrutinizer05since aiui it is pretty much terra incognita regarding that21:50
wpwrakregarding maturity, the siglent hardware seems to be quite good. their firmware is still behind rigol but they're updating it frequently (and you don't need windows to update it :), and they're listening to customer feedback21:51
wpwrakyou could have a look at the "remote control" of the siglent sds1000. the sds2000 will apparently be a superset of that. maybe they've already released it, dunno. last time i checked was about a month ago.21:52
wpwrakbut if you prefer rigol, there's nothing wrong with that. both have what i'd consider very reasonable choices.21:52
DocScrutinizer05given both seem to not support a parallel LA21:54
DocScrutinizer05a 2ch is a nogo21:54
DocScrutinizer05again, let's think a PSU, e.g. the critter that does LCD backlight in N90021:55
DocScrutinizer05you'd prolly want to record more than just 2 signals, though at least some of them are interesting on logic level only21:56
wpwrakboth have LA variants/options21:56
DocScrutinizer05ooh21:56
wpwrakwell, DS1000Z, DS2000A, and SDS200021:56
wpwrakin the case of SDS2000 it's a real option (you get the license key and the cable kit), in the case of the rigols it may be a different product code. but the base scope is DS1000Z or DS2000A21:57
DocScrutinizer05and LA and scope can run in parallel?21:57
wpwrakyes21:58
DocScrutinizer05cool21:58
wpwrakyou can find these things on the eevblog fora ;-)21:58
DocScrutinizer05mhm21:58
wpwrakthere's one where one guy is painstakingly going through every little feature of the sds2000, measuring exactly how the hardware performs, etc. ;-)21:59
DocScrutinizer05let's start with sth simple: do you know of any operation that can't get done via remote but only on device UI?21:59
wpwrakdunno. i see the two as fundamentally different ways of using the scope. you're either in local mode or remote mode. mixing them may be difficult and awkward.22:00
DocScrutinizer05and how fast can you download/sync the display via remote? also, complete display, or waveform only, or both?22:01
wpwrake.g., i don't even know if you can command my ds1000cd to exit remote mode (other than by pressing a button)22:01
wpwrakthat'll be MUCH slower than the local screen22:01
DocScrutinizer05yeah, that's expected22:01
DocScrutinizer05that's why I asked "how fast"22:02
DocScrutinizer05as in fps22:02
wpwrakwhat i sometimes did (before comms died) was capture a waveform with local controls, then download the visible area at high resolution for further processing22:02
wpwrakin the ds1000cd, communication is quite slow, so that generally takes a while. also, the ds1000cd could only transfer the "visible area", so i had to zoom in and step screen by screen through the waveform. messy.22:03
DocScrutinizer05maybe I should already go for a display/UI-less scope22:03
wpwraki wouldn't :)22:03
DocScrutinizer05I'm afraid that would force me into wincrap usage22:04
wpwrakbesides, most of them are crap22:04
wpwrakyes, and that too22:04
DocScrutinizer05but at least you could be sure that all remote controls are actually there ;-P22:04
wpwrakyes, and none of the local controls :)22:05
wpwrakbut i wouldn't worry about the remote controls. also with a regular scope, you'll have at least what those "headless" scopes have.22:06
DocScrutinizer05(zoom in, go step by step through waveform) that's exactly one thing I'd expect to be able to do completely sw controlled via remote. Or I'd first shoot the device and then the manufacturer22:06
wpwrakthe problem with this mode of operation is that what i actually want is to read every Nth sample, from the Sth to the Eth sample.22:07
wpwrakif comms are fast, i don't mind if N is always 1.22:07
DocScrutinizer05also, no download of raw sampe data is a death penalty for the one who built that crap22:07
wpwrakyes, that's the problem with the rigol ds1000cd22:07
wpwrakand to make things more interesting, you need to predict certain "dead times" of the scope when processing commands. else, it'll lose commands.22:08
DocScrutinizer05given that rigol is supported by sigrok, I wonder how they do it22:08
DocScrutinizer05OUCH!!!22:09
wpwrakbut i'd expect that more modern scopes don't have that sort of bugs anymore22:09
wpwrakof course, for example my fluke 8845a, not a "cheap toy", sometimes resets tcp connections ...22:09
DocScrutinizer05do you think all those DSO crap items use winCE internally?22:09
wpwrakdunno what they use22:10
wpwraki think they sometimes have weird hardware. e.g., maybe board X talks UART, then board Y turns that into USB. so you get USB, but with UART performance.22:10
wpwrakthen add insufficient buffering and such, and there you are22:10
DocScrutinizer05hmmm22:11
wpwrakagain, the more modern, the more likely such detours won't exist22:11
DocScrutinizer05sounds like an inefficient and expensive way to build such stuff22:11
wpwraklow frequency of innovation22:11
wpwrakmeasurement equipment has very long life cycles. maybe 10x that of, say, a smartphone :)22:12
wpwrakso if *everyone* speaks USB natively, they may start to bolt a USB-to-serial on their RS-232 :)22:12
DocScrutinizer05that may actually be a plus for siglent then22:12
DocScrutinizer05nowadays you do that sort of stuff in firmware22:13
wpwrakDS1000Z, DS2000A, and SDS2000 are roughly the same generation. siglent are a bit newer, but not by much.22:13
DocScrutinizer05in a generic universial hw platform22:13
wpwrakyes, USB is no longer a stranger22:13
DocScrutinizer05I'd rather expect to find all sorts of not(-yet)-used unsupported hw stuff on such a device nowadays, like ethernet, sockets for more RAM, whatnot else22:15
DocScrutinizer05SATA22:15
DocScrutinizer05aiui they already hacked and REed the rigol firmware, no?22:16
DocScrutinizer05((DS2000A, and SDS2000 are roughly the same generation. siglent are a bit newer, but not by much.)) why is rigol supported by sigrok thren, and siglent not?22:19
wpwrakhacked with the goal of enabling features that would require a license, yes22:23
wpwrakproper RE, no22:23
wpwrakask the question again in a few months ? :)22:24
DocScrutinizer05http://www.eevblog.com/forum/projects/rigol-ds1102e-data-transfer-demo-program/msg153265/#msg15326522:25
wpwrakseems that he's learning about the quirks of the 1000e/d series, successor of the even quirkier 1000c/de :)22:27
wpwrakerr, c/cd22:27
wpwrakbut i can tell you that one can retrieve all that stuff from the 1000c/cd and given that e/d are very similar, i'd expect no less from them22:28
wpwrakbut, as i said, it's slow. i'd expect modern scopes to do much better.22:29
DocScrutinizer05http://www.eevblog.com/forum/chat/using-rigol-ds1052e-for-spectrum-analysis/ hmmm22:30
DocScrutinizer05actually I've been looking for ds200022:31
DocScrutinizer05aaah finally: http://www.eevblog.com/forum/blog/eevblog-369-rigol-ds2000-oscilloscope-playing-around/msg197330/#msg19733022:33
wpwraki'm not going to read all that stuff again ;-))22:35
wpwrakbesides, the 1000c/cd/e/d series already got discussed to death many years ago. lone before eevblog even existed :)22:36
wpwrakit's so long ago, i don't even remember where we discussed that :)22:36
DocScrutinizer05:-S http://www.eevblog.com/forum/blog/eevblog-369-rigol-ds2000-oscilloscope-playing-around/msg174898/#msg17489822:37
DocScrutinizer05>>I seem to have found the first bug in the DS2000 that is, IMO, rather a serious one:<<22:38
DocScrutinizer05yes, sure, not much use in ds1052 stuff, just it's examples of what I would like to do and maybe is not possible, even in ds2000 series, according to last URL I posted22:47
wpwrakthat issue is more than 1.5 years old. may have been solved since. ask marmad / post question in thread ?22:49
DocScrutinizer05sure22:53
DocScrutinizer05it's just worrying that there's been no update in the thread22:53
DocScrutinizer05particularly after 1.5 years already22:53
wpwraknot too uncommon. problem goes away, people forget about it.22:54
DocScrutinizer05hmmm22:54
wpwrakalso, there are several rigol 2000 threads on eevblog.22:54
wpwraksome are very very long22:54
DocScrutinizer05yeah, annoying22:54
wpwrakfora just don't work very well :)22:54
DocScrutinizer05took me around 30 min to find the *first* one related to 2k series22:54
wpwrakthere's one with something like 300 pages i think :)22:55
DocScrutinizer05and in last post marmad refers to another one but doesn't give a link22:55
DocScrutinizer05>>...post it in the Rigol REVIEW thread.<<22:56
DocScrutinizer05KTNX22:56
DocScrutinizer05I guess getting a scope is more hassle to do it right than i'm willing to invest into that right now23:00
DocScrutinizer05on a faintly related sidenote: did you ever try to figure with which max TX power (in Watts) a CMU200 can produce a RF signal?23:03
DocScrutinizer05the more complex the device, the more tedious and complicated it gets to find answers to pretty simple questions23:03
DocScrutinizer05like "what power does CMU200 TX do?" or "Does rigol DS2k allow proper download of full raw waveform data?"23:04
DocScrutinizer05when finding the answer involves stuff like "ask on the forum thread maybe?" then I'm usually out23:06
DocScrutinizer05not like siglent website was *any* better in their FAQ or datasheets or forum or whatever23:07
DocScrutinizer05so all you can do is weeks of googling and hoping, and finally buy one of the critters and then send it back on warranty when it doesn't support the stuff it's supposed to support23:08
DocScrutinizer05and either waste weeks on all that, or get somebody else doing it for you23:08
DocScrutinizer05annoying23:09
DocScrutinizer05anyway this little episode convinced me of one thing: buy scope only locally so you can kick the ass of seller physically23:12
DocScrutinizer05or don't buy at all, rather rent23:12
DocScrutinizer05for a day or a week23:13
DocScrutinizer05renting also serves yet another purpose: you plan your task before you start it23:14
DocScrutinizer05or - to go back to square one of today - you start small and cheap and get 3 or 4 of those dirt cheap 16/8/4/3/2 chan LAs23:17
DocScrutinizer05when those turn out to be crap, you still can practice hot air reflow on them23:18
DocScrutinizer05note to self: consider a special mode in signal conditioner stage for LA to transform it into a flash A/D. With proper circuit, a 8 opamps should be fine for full 8bit A/D (feed back D/A converted output of higer bits to the inverting input of lower bit opamps)23:22
DocScrutinizer05I wonder why I can't recall ever having seen this type of A/D anywhere23:26
DocScrutinizer05hmmmm, kinda similar to http://de.wikipedia.org/wiki/Datei:DMT_ADU_mit_DAU.svg23:29
DocScrutinizer05but parallel instead of serial23:30
DocScrutinizer05Uin: [0..Umax[;  output:b0,b1 [00, 01, 10, 11]; 01:="Uin > Umax/5 * 2", 10:="Uin > Umax/5 * 3, 11:="Uin > Umax/5 * 4;   comparator0-out=b0:= " Uin > ( (Umax/5 *1) + {b1 * ( Umax/5 * 3) } ) "; comparator1-out=b1:= "" Uin >  (Umax/5 * 3)"23:45
DocScrutinizer05dang!23:46
DocScrutinizer05Uin: [0..Umax[;  output:b0,b1 [00, 01, 10, 11]; 01:="Uin > Umax/4 * 1", 10:="Uin > Umax/4 * 2, 11:="Uin > Umax/4 * 3;   comparator0-out=b0:= " Uin > ( (Umax/4 *1) + {b1 * ( Umax/4 * 2) } ) "; comparator1-out=b1:= "" Uin >  (Umax/4 * 2)"23:49
--- Sun Aug 24 201400:00

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