#eevblog - 2021-03-03 - AustNet Archive Project

// #eevblog — 2021-03-03

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« 2021-03-02 2021-03-04 »
05:04 Quit: Halcyon ([email protected]) EOF from client
05:06 Join: Halcyon_ ([email protected]) to #EEVblog
11:44 * steve30 paws at Halcyon_ 
12:14 * Ysjoelfir gets scissors to cut off Halcyon_ 's dangly bit
19:43 * rust_collector bumps into an Ysjoelfir 
20:16 * Ysjoelfir accidentally stabs the scissors into rust_collector
23:30 Join: TomKge ([email protected]) to #EEVblog
24:09 <rust_collector> oh no, now I can not have an mri
24:30 <Ysjoelfir> damn!
24:45 <rust_collector> well, that is annoying
25:07 <Ysjoelfir> indeed!
25:13 <TomKge> Hello, I have a problem with a Sallen-Key Highpass filter which will be used in an analog front-end for phase sensitive measurements. I used C0G-Caps but there is a significant temperature drift.
27:29 <TomKge> The op-Amp I am using is ADA4177
29:57 <Ysjoelfir> well, I doubt the drift is coming from the caps if you used NP0 ones...
30:59 <TomKge> What I can also observe is an offset drift when I only heat/cool the caps. Heating increases offset, cooling decreases
31:47 <Ysjoelfir> are you sure you are not influencing nearby components in any way, as well as eg. the copper traces which have a TERRIBLE tempco?
32:59 <TomKge> You are right. I also heat/cool the wires on which I attached the Caps to
34:08 <TomKge> but will the traces really affect the frequency response by that much, when the resistors used are in the 100s of kiloohms range?
35:12 <TomKge> to be explicit: Caps are 220nF, Resistors 180k
37:23 <T3sl4> impossible to say without sch and layout
37:41 <Ysjoelfir> I agree
37:44 <T3sl4> and what is drifting
37:56 <TomKge> Is there another possibility to get a DC-coupling without significant phase drift with temperature
38:07 <coppice> T3sl4: driving badly with style
38:11 <T3sl4> also, do you know they're C0G, or did you get scammed i.e. from chinese parts or something
38:15 <T3sl4> coppice: indeed
38:22 <TomKge> the phase is drifting. I was assuming, that this is due to the filter frequency shifting
38:55 <TomKge> @T3sl4 - at least I ordered fro mouser...
39:39 <T3sl4> ok
39:42 <T3sl4> also what cutoff freq
41:39 <TomKge> cutoff is 4 Hz
44:21 <T3sl4> i wonder if the resistors might be too large
44:23 <T3sl4> or unbalanced?
48:00 <TomKge> https://upload.wikimedia.org/wikipedia/commons/thumb/e/ec/Sallen-Key_Highpass_Example.svg/310px-Sallen-Key_Highpass_Example.svg.png
49:06 <T3sl4> resistance to the amp inputs that is
49:21 <TomKge> I made R2 double the resistance of R1 and didnt connect it to ground but to a 2.5V-source in order to get a 2.5V offset while having a single-ended power supply to the Opamp
50:04 <TomKge> R1 = 180k, R2=360k
56:46 <TomKge> https://ibb.co/YX4t1Pk
00:29 <TomKge> Could you explain the effect of unbalanced resistors? How do they affect the phase?
10:44 Join: arch ([email protected]) to #EEVblog
17:32 <TomKge> What can I do to make the filter as temperature stable as possible in terms of the phase drift?
21:37 <K> what does the opampts datasheet say about temp drift?
51:56 <arch> T3sl4, look at this nice startup waveform with proper compensation on the AOZ1073! (the little blip you see around 4.5V is due to my lamp, with a cc led boost converter starting up). i show off now :D https://i.imgur.com/Kv39hEN.png
52:13 <T3sl4> :))
52:44 <arch> started from the bottom, now we here :3
53:28 <TomKge> around 100µV offset Voltage in the desired temperature range. But does an offset voltage affect the phase of the ac-coupled signal?
25:18 <arch> this is really confusing me. why is there a 27kHz ripple on top of the 500kHz operating frequency;s ripply...
25:44 <arch> https://i.imgur.com/L2Virqy.png
26:01 <arch> so i have a 2A static load, then i apply a 1A transient load
26:37 <arch> im just thinking this conv is a piece of crap without a ground plane. very sensitive to noise?
29:45 <K> external noise or crap from circuit itslef?
29:49 Join: TheDude ([email protected]) to #EEVblog
30:13 <arch> could be either...but i am using a shielded inductor, so i dont think inductor noise should be doing that
32:42 <arch> literally the only thing ruining my day right now...
33:42 <arch> comp is good, seems to be stable. not sure why it dips down 250mV...that seems a bit excessive. the datasheet shows 100mV dip, but they have it running at 3.3V output. mine is at 5V out
34:32 <T3sl4> what's the source?
34:49 <arch> my lab psu
34:59 <T3sl4> linear?
35:02 <arch> yes
35:07 <T3sl4> ah
35:20 <arch> i put it on maximum current limit too, 2A
35:35 <arch> let me try with my 12V SLA battery
35:41 <K> put the thing inside tin box?
35:42 <T3sl4> is it not aliasing by the scope
39:02 <arch> or maybe it's cuz im using an opamo load?
39:08 <arch> opamp dc load
39:56 <T3sl4> is it badly compensated?
40:24 <arch> i don't think so. i mean, i followed along to their given equations
40:38 <arch> https://i.imgur.com/L2Virqy.png
40:47 <T3sl4> the amp i mean
41:09 <arch> i need to just get a bigass rheostat...
41:21 <T3sl4> big assrho, stat
41:26 <T3sl4> assrheo*
41:43 Quit: TomKge ([email protected]) Quit: http://www.kiwiirc.com/ - A hand crafted IRC client
43:01 <arch> i dont have proper comp on the dc load opamp
43:18 <arch> it's the standard linear load schematic you get on google images lol
44:59 <T3sl4> well, you might scope it and see. if it's oscillating it's probably not accurate either
46:23 <arch> this should be good enough? https://www.ebay.com/itm/Ceramic-Tray-Wire-Wound-Variable-Resistor-Rheostat-100W-10-Ohm/311061066695
46:54 <T3sl4> yummy
51:10 <Ysjoelfir> mornings
51:42 <rust_collector> do I have to?
51:43 * T3sl4 hands Ysjoelfir a tea
52:27 * rust_collector makes cabbage and potato tea for Ysjoelfir 
54:32 <Ysjoelfir> No idea how that tastes, but its ok
54:34 <Ysjoelfir> thanks
54:42 * Ysjoelfir teas twice
56:52 <Ysjoelfir> oh, btw, mr. Williams
57:06 <Ysjoelfir> I just got "your" book
58:01 <arch> know what, im gonna order my PCB off oshpark. double sided board. i want to get to the bottom of this fking annoying mystery
58:28 <arch> route feedback on the back layer surrounded by gnd plane
58:59 <arch> literally the only buck IC that has given me trouble
59:21 <arch> then again, my sample size so far is small :3
01:17 <T3sl4> oh nice
01:28 <T3sl4> i've been meaning to read "my" books some time, let me know how they are
02:10 <T3sl4> arch: w...what else is small? owo
02:52 <Ysjoelfir> I did get the circuit designer's companion. been looking into it for a few minutes right now, looks not to bad
03:31 <K> link to the book or it didn't happen
03:59 <Ysjoelfir> https://www.amazon.de/Circuit-Designers-Companion-English-ebook/dp/B006WW6PMC/ref=sr_1_2?__mk_de_DE=ÅMÅŽÕÑ&crid=1LQ9QSH2OD9SY&dchild=1&keywords=circuit+designer+companion&qid=1614701031&sprefix=circuit++designers+%2Caps%2C168&sr=8-2
04:19 <K> holly fuck, ÅMÅŽÕÑ
04:39 <K> ŽŽŽŽŽŽŽŽ
04:53 <Ysjoelfir> yes, mr. williams is a world known bestseller author,
04:58 <Ysjoelfir> ..
05:13 <arch> T3sl4, i didnt know you were an author
05:28 Join: Kuschelpony ([email protected]) to #EEVblog
05:31 <T3sl4> one of us, anyway
05:49 <T3sl4> there's a lot of *im williams's out there
05:49 <arch> uh huh...shuuureee...
05:54 * arch goes to pirate T3sl4's book
08:07 <Ysjoelfir> I think I'll cook Pommersches Glipsch today or tomorrow
08:23 <Ysjoelfir> who wants to join in and do it together with me?
11:38 <Ysjoelfir> Oh, rust_collector, K and T3sl4 want to? Nice! :D Its very easy actually
12:01 * T3sl4 won't give a hand, but offers a bowl
12:29 <Ysjoelfir> I'm not sure that your arm is that long
13:10 <T3sl4> no, my arm is normal, the bowl is long
14:16 <Ysjoelfir> :P
14:23 <Ysjoelfir> Do you like milksoup?
15:13 <TheDude> did you make a milkwish?
15:21 <Ysjoelfir> no.
15:46 <T3sl4> i don't know if i do, but it sounds alright
15:48 Join: Watcher ([email protected]) to #EEVblog
16:32 <TheDude> you should have
16:33 <TheDude> https://www.youtube.com/watch?v=kJ3QSdWxUPI
17:43 <Ysjoelfir> I was close to asking if there is anything going to happen besides "donk... donkdonk... donk.... donkdonk", but then it went great all of the sudden :D
18:14 <TheDude> intros of electronic songs are always very repetitive
18:17 <TheDude> as are outros
18:20 <TheDude> allows for mixing
18:39 <Ysjoelfir> As an old time raver I noticed that^^ But that felt very long for some reason
34:42 Quit: Kuschelpony ([email protected]) Connection closed
38:56 Quit: Watcher ([email protected]) Quit: i'am out
40:09 <rust_collector> well, if you don't mind me being sick, then yes, I am there
41:13 <rust_collector> the rule is the first half has to be a boing boing boing, then there is 1/6 that is interesting, then you have a boring outro
41:43 <rust_collector> Ysjoel the "old time" raver kid
43:14 <rust_collector> oookay, I think it is getting ready for work time
43:25 <rust_collector> have funners and many enjoys
43:44 <K> no u.
44:03 <Ysjoelfir> :P
44:20 <rust_collector> why?
44:30 <K> cause.
44:37 <Ysjoelfir> yes
45:11 <Ysjoelfir> take a stove, a pot, some milk, salt, sugar, pearl barley and vanilla with you when you go. you can cook while driving
46:16 <TheDude> rust_collector, no u
46:24 <TheDude> it's a good song
46:26 <rust_collector> i know that, but... I still do not handle milk very well, lol
52:12 <Ysjoelfir> thats fine
24:54 <K> they have drugs for that
30:22 <T3sl4> Ysjoelfir: i'd call that a... well, it'd be a pudding if it were an egg custard
30:50 <T3sl4> (more traditionally? with a grain like rice, or a not-grain like tapioca)
01:26 Join: Ysjoelfir_ ([email protected]) to #EEVblog
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04:17 Nick: Ysjoelfir_ is now known as Ysjoelfir
13:58 Join: Kuschelpony ([email protected]) to #EEVblog
35:01 Join: kn0ppers ([email protected]) to #EEVblog
38:56 Nick: Halcyon_ is now known as Halcyon
39:01 Quit: Halcyon ([email protected]) Quit: Leaving
39:14 Join: Halcyon ([email protected]) to #EEVblog
39:26 * Ysjoelfir jumps at Halcyon and hugs him
39:35 <Halcyon> :)
39:38 <Halcyon> Morning
41:12 * T3sl4 , noticing Halcyon's entrance, looks away and pouts
41:34 <Halcyon> Bitch :P
41:46 <T3sl4> nah
41:48 * T3sl4 glomps Halcyon
42:04 <Halcyon> Mmmm coffee
42:27 <Ysjoelfir> Halcyon, do you want to make a cooking colaboration with me? Like I suggest a recipe I am not brave enough to cook and then we do it together, each by himself?
42:40 <Halcyon> Yes!
43:25 <Ysjoelfir> you sure? I suggested the recipe here and in "The other EEVBlog Channel(Trademark)", nobody wanted :(
43:32 <Halcyon> Like live? Or in our own time?
43:42 <Halcyon> Hahaha trademark :P
43:45 <Ysjoelfir> however you like^^
44:03 <Halcyon> Well, for instance, what kind of meal? I assume you are talking about a lunch/dinner thing?
46:19 <Halcyon> There are a few ways I can think of running this... do you use Signal? Maybe give me a call to discuss?
48:50 <Halcyon> Oh yeh, I have you on Signal already :P I'll message you my number, maybe when you're free we can have a chat. I need to be heading to work shortly so we'll talk soon.
44:38 Quit: kn0ppers ([email protected]) Connection closed
51:24 <T3sl4> https://i.imgur.com/vbgpceh.gifv
58:04 Quit: Kuschelpony ([email protected]) Connection closed
59:32 Quit: arch ([email protected]) Ping timeout: 121 seconds
28:15 Join: arch ([email protected]) to #EEVblog
21:45 <steve30> hi Halcyon
42:06 Quit: arch ([email protected]) Ping timeout: 121 seconds
01:19 <steve30> I've uploaded a new video to the steve30 youtube channel
01:26 <steve30> It includes a "shocking" clip
24:45 <T3sl4> electro30?
24:47 <T3sl4> steveboom?
32:35 <steve30> Just switch-mode PSU leakage, but still enough to make me jump and drop my screwdriver.
57:33 <rust_collector> poor screwdriver
02:07 * rust_collector is wondering if marshmallows are fluffy enough, that you would lose weight, if you ate a bag of them before dinner, or if they are so full of sugar, that it would not work
03:52 <steve30> probably too much sugar for losing weight
04:23 <rust_collector> I think so too, but i still think it would be worth trying, lol
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21:06 <rust_collector> a test point specifically for cooking your scope, that is nice
28:41 <rust_collector> that was a pretty interesting video, imo. I don't know a thing about those devices.
29:05 <rust_collector> ok, maybe a thing or two, but no details
32:06 <steve30000> I was careful to use insulated tools for the rest of that project
32:15 <rust_collector> hah
32:18 <steve30000> well, while the oscilloscope was connected anyway
33:32 <rust_collector> now you know why you need a dso138 from china...
33:38 <rust_collector> or something similar
34:45 <steve30000> The shock only happened because the camcorder I was filming with was connected to a mains PSU. If I'd battery powered it instead I'd have been fine :).
35:24 <rust_collector> yep, or if you had a tiny battery powered scope. same idea, I guess.
35:35 <rust_collector> Ok, I just miss my crappy little scope
36:12 <steve30000> I used to ponder getting one of those little Chinese scopes, but decided to get a proper one instead.
36:20 <rust_collector> good.
38:27 <rust_collector> i do miss that little thing. the switches gave up on it. but it was very handy for things like wheel speed sensors and such, as you could just carry it around, and it ran from a 9v battery. I have thought about one of those "dso shell" ones, which is similar, but has the encoder button, in stead of all the little switches
39:17 <rust_collector> but it is a very very small screen, and it is probably very limited in many ways, so getting a proper scope first was a good idea
42:56 <rust_collector> I was pretty impressed by the jyetech customer service. I asked what kind of switches they were, so I could order some, but he insisted on just sending me a set of them, and they sent it express, so I had them in a few days. and that is just a little cheap toy device, which is probably not worth the cost of shipping the switches
48:06 <steve30000> nice
58:23 <rust_collector> anyway, I would like more videos like that. maybe even with a bit more details, if you feel like it some time. My experience with tape things is limited to cleaning and replacing belts
00:14 <steve30000> I will do more as and when I need to repair things. I'm not all that geared up for doing Dave/bigclive/etc style repair videos though. My tripod easily gets in the way of what I'm doing.
00:44 <steve30000> I do need to look at an old VHS deck sometime. I'm sure the fault with that will be fairly simple though.
02:33 <rust_collector> that is fine. we already have the dave and clive. But I think there would be some interest in how such things work, because they are "no longer a thing"
03:47 <rust_collector> well, you do what you want, but if you do somehting like that some time, you would get at least one view, lol
03:53 Join: Dude ([email protected]) to #EEVblog
04:27 <steve30000> I'm sure I'll find some things to make videos of
06:51 Quit: TheDude ([email protected]) Ping timeout: 121 seconds
08:01 <steve30000> mmm, that coffee was nice
08:04 Nick: steve30000 is now known as steve30
08:22 <rust_collector> coffee??? good idea
43:21 Quit: Dude ([email protected]) Ping timeout: 121 seconds
52:24 <T3sl4> electrohead: what was that beer brand again? i keep forgetting
52:56 <rust_collector> barn hammer brewing
01:59 Join: kantlivelong ([email protected]) to #EEVblog
02:00 <T3sl4> yeah, didn't see em at the store
02:23 Quit: Tw|tch ([email protected]) Ping timeout: 121 seconds
02:37 <kantlivelong> hah didnt realize there was an irc
02:54 Join: Tw|tch ([email protected]) to #EEVblog
03:16 <T3sl4> there are dozens of us
03:17 <T3sl4> dozens!
03:41 <kantlivelong> haha
03:54 <kantlivelong> ill have to add this to my bouncer
05:16 <steve30> IRC ftw
05:31 <kantlivelong> i even use IRC for steam and hangouts
06:03 <rust_collector> very nerdy
06:07 <kantlivelong> indeed
07:06 <T3sl4> sounds like a moral imperative
07:31 <kantlivelong> one chat client
09:54 * kantlivelong is trying to figure out what inductor would be sufficient for usb data. buddies midi keyboard fell and broke the usb port and the inductor[s] blew up.
10:17 <kantlivelong> thought i had it repaired just by replacing the usb port but totally missed the vaporized bits
13:00 <T3sl4> data doesn't have inductors, it sometimes has a common mode choke though
14:14 <kantlivelong> ah then thats what it is. https://www.fullcompass.com/common/products/original/243384.jpg
14:22 <kantlivelong> L2 right behind the USB
17:00 <T3sl4> lol, X2Y caps to the DIN connectors
17:04 <T3sl4> (MIDIs?)
17:15 <kantlivelong> its a usb midi keyboard yeah
18:33 <kantlivelong> i figured maybe it would be a common part that could be whacked in but havent found much yet.
19:25 <kantlivelong> ... but knowing the right criteria would help. haha
19:39 <T3sl4> just jumper over it if nothing else, it doesn't really do much
20:20 <kantlivelong> yeah i did that to test and worked. i figured if cant find it then can leave it.
22:38 <T3sl4> what size is it, 1206, 1812?
24:10 <T3sl4> oh or maybe smaller, i dont see any in 1812
25:22 <kantlivelong> well the footprint is ~3mmx2mm
26:49 <T3sl4> yeah 1206 (3.2 x 1.6mm)
27:06 <T3sl4> pretty much whatever should do, i guess https://www.digikey.com/short/f0zzq0m4
27:26 <kantlivelong> yeah on it. :)
28:00 <kantlivelong> 2 results haha alright then
29:24 <T3sl4> seems they aren't all categorized as chip types, you'll have to sort out dimensions
29:52 <kantlivelong> ah yeah.
30:04 <kantlivelong> <- noob
30:53 Quit: coppice ([email protected]) Quit: Konversation terminated!
31:41 <kantlivelong> DLP31SN121ML2L seems like its it though.
31:54 <kantlivelong> "USB lines of digital AV equipment such as digital cameras"
34:07 <T3sl4> yeah
34:38 <kantlivelong> hey thanks T3sl4.
34:48 <T3sl4> yw
36:32 <kantlivelong> repairs are the best
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33:32 <T3sl4> definitely not steve30 irl https://www.youtube.com/post/UgyhwbyLZECT2Qm7HbN4AaABCQ
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44:56 <hsn> https://youtu.be/0DBnGYMPaf4?t=119
04:46 Quit: Ysjoelfir ([email protected]) Changing hosts
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04:55 Mode: (by ChanOP) +o Ysjoelfir
05:40 <Ysjoelfir> mornings
18:40 Quit: kn0ppers ([email protected]) Quit: Leaving...
26:21 <Halcyon> Howdy
28:19 <Ysjoelfir> Mornings sweetheart :P
28:25 <Ysjoelfir> Did you receive my message?
28:27 <Halcyon> I did
28:38 <Ysjoelfir> weee
28:55 <Halcyon> Sounds like a plan
29:01 <Halcyon> What is the time difference by the way?
29:03 <Ysjoelfir> I'm always not sure because of the registration thing from austnet preventing messages and stuff :D
29:05 <Ysjoelfir> erm
29:07 <Ysjoelfir> EEVBlog time
29:07 <EEVBlog> Ah shoot, Doc! We've ended up at 19:29 Sydney time.
29:17 <Ysjoelfir> you are +10h
29:33 <Halcyon> Mmmk yeh so it would have to be an alternating thing
30:51 <Ysjoelfir> I mean, the thing I found would be a desert/sweet dish kind of thing anyways, so that could be done for dinner and breakfast as well. But I think it would be the ideal way to alternate :D
31:05 <K> hello squids
31:29 <Ysjoelfir> Hi mr. octopussy
33:05 <Halcyon> Did you have a first dish in mind?
34:26 <Ysjoelfir> Yes. I was looking for a dish my granny made for me in my childhood when I found a... simmilar thing with a twist. Its a milk soup with barley and vanilla pudding to thicken it. the original recipe granny made was without those and way more simple, but delicious as a sweet dish
45:27 <Halcyon> Hmmmm I'm not huge on sweet things
46:02 <Ysjoelfir> But you are such a sweet guy, you must! :P
46:13 <Halcyon> :P
46:18 <Halcyon> I'm sweet enough
50:21 * Ysjoelfir licks Halcyon
50:22 <Ysjoelfir> hm
50:27 <Ysjoelfir> no, needs a bit more.
50:30 <Halcyon> :P
50:37 <K> no biting!
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03:22 <Ysjoelfir> I wonder about this ADC... somehow the ADCs influence each other, despite leaving plenty of time between switching channels.
14:01 Quit: Meroje ([email protected]) Quit: bye!
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52:46 * Ampera sneezes at Halcyon 
15:55 <K> internal crosstalk ?
36:56 <Ysjoelfir> probably, but why?
37:23 <Ysjoelfir> or even better, how can I mitigate that? Atmel suggests discarding the first result, which I do. doesn't realy help
39:03 <Ysjoelfir> never had such a problem before as well, it always worked rather god
39:08 <Ysjoelfir> good
40:06 <Kuschelpony> i missed the earlier part before i joined, do you talk about the ADC in an mikrocontroller?
40:15 <Ysjoelfir> yes.
40:23 <Ysjoelfir> [11:03:20] <@Ysjoelfir> I wonder about this ADC... somehow the ADCs influence each other, despite leaving plenty of time between switching channels.
46:36 <K> do you need to read them at the same time?
46:45 <K> maybe turning off input will help
46:45 <Ysjoelfir> no, and I don't
46:51 <Ysjoelfir> I did, they are off
46:59 <K> then i dunno :/
47:06 <K> maybe the signals are bad?
47:30 <Ysjoelfir> 5v through 100k and a 100k NTC, middle of that goes to the ADC. should be fine imho?
47:37 <Ysjoelfir> also, all is pwoered by a battery
48:43 <Ysjoelfir> I am almost sure its some parasitic shit
49:29 <K> monkey business with avcc
50:19 <Ysjoelfir> its the same as AVDD, decoupled by a ferrite bead and a cap
57:56 <Kuschelpony> sorry for my delay
58:18 <Kuschelpony> basically the ADC input is a capacitor and sores part ofd the last voltage when switching to a new input
58:31 <Ysjoelfir> right.
59:08 <Kuschelpony> but 100k and the few pF should have no big issues to need not more than few mSek until the new value is stable again
59:55 <Ysjoelfir> exactly what I thought
01:15 <Kuschelpony> brainsync complete :)
01:26 <Ysjoelfir> hahaha :D
06:27 <Kuschelpony> hmm, try to find more ideas but currently i dont have any
07:41 <Ysjoelfir> I mean, the program works even with that small mistake, but I would love to have it correct :D
09:16 <Kuschelpony> sure
09:59 <Kuschelpony> i really should do own programming and not just do the hardware for others
10:17 <Kuschelpony> then i could probably tell much more about such issues
10:20 <Ysjoelfir> I thought it might be "residual" charge from what do I know, so I even tried setting the pins to be a grounded output, but meh, didn't work either
10:45 <Ysjoelfir> welcome to my world, mr. pony... THAT is why I recently started to do programming again :D
10:50 <Kuschelpony> hmm, residual charge sure, but not at the pin itself but in the sampel and hold capacitor inside
11:07 <Ysjoelfir> well, can't realy reach that one ;)
11:19 <Kuschelpony> mmh, i wish i could really program, at least i can say for sure that all varaiants of C are the wrong language for me
11:20 <Ysjoelfir> oh wait, I could
11:32 <Kuschelpony> sure you can, just repeat the sampling
11:57 <K> Ysjoelfir, if you short the other adc out, it goes away?
12:00 <Ysjoelfir> you can't sample with the pin being an output. but I can sample the GND
12:04 <K> wich mcu is it?
12:04 <Ysjoelfir> yes, K
12:12 <Ysjoelfir> ATMEga48P
13:34 <K> hm, the digram shows that adc is somehow connected to port c
13:40 <Ysjoelfir> yep
13:49 <Ysjoelfir> I use portC only for the ADC
13:53 <Kuschelpony> i will leave again, my headache is not getting better here, might help to walk out a few km at fresh air
14:02 <Ysjoelfir> Enjoy :)
14:06 <K> ah that is data ofc
14:42 <K> hm
18:01 <Ysjoelfir> hm. tried selecting the internal ground as ADC Source and sampling a few of those before switching to my wanted input and sampling that. its... better, but still noticeable.
18:28 <steve30> hi
18:34 <Ysjoelfir> hi steve :)
18:56 * Ysjoelfir offers steve30 a place in the big cozy kitty bed, tight on his feet
20:08 <K> and aref is not floating or anything funny
20:26 <Ysjoelfir> aref is AVCC
20:46 <Ysjoelfir> and the needed cap is connected to AREF, yes
21:01 Join: coppice ([email protected]) to #EEVblog
21:38 <K> well, there is only one adc in there
21:52 <Ysjoelfir> yes.
22:03 <Ysjoelfir> its to be expected to have SOME crosstalk
22:51 <Ysjoelfir> but if I turn the pot say.... from 512 to 1023 I get a change of ~70 in the ADC with the sensor
23:05 <Ysjoelfir> thats 7%... a bit much for my liking
23:19 <Ysjoelfir> well, with grounding not I got it down to ~2%
23:25 <Ysjoelfir> *now
32:17 Quit: Kuschelpony ([email protected]) Connection closed
47:53 Join: Kuschelpony ([email protected]) to #EEVblog
52:40 Quit: Kuschelpony ([email protected]) Connection closed
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