Activity for Lundin
| Type | On... | Excerpt | Status | Date |
|---|---|---|---|---|
| Comment | Post #279492 |
That being said, professional repair of cables means replacing the cable. Spliced cables are generally frowned upon, particularly in an automotive environment where there's some major oxidation and moisture present. One classic problem is where someone has spliced a cable, the joint is fine electrica... (more) |
— | over 3 years ago |
| Comment | Post #279302 |
Interesting answer, thanks. I don't understand why this was down-voted either. (more) |
— | over 3 years ago |
| Comment | Post #279278 |
Regarding the "urgent" part, this should be covered by some network-wide policy against "fluff" like SE got. Irrelevant things such as "URGENT!" should simply be edited out. I'd down vote such posts too. But the "fluff" does not however necessarily make a post off-topic. The kind of posts with "URGEN... (more) |
— | over 3 years ago |
| Comment | Post #279250 |
@coquelicot Only these specific quoted parts that are about homework, for this discussion here. (more) |
— | over 3 years ago |
| Comment | Post #279250 |
@Olin Lathrop You are kind of missing the point that the people who do take the time to read this text are not likely the homework dump crowd. The bluntness makes us come across as elitist and gives a bad impression of the site to those who are sensible enough to do read the help before asking a ques... (more) |
— | over 3 years ago |
| Comment | Post #279103 |
@Monica Cellio If that 4th slide means the question isn't visible on the site and the info is only visible to the poster (+those giving feedback & moderators), then I like it a lot. Possibly have something like a comment field that only exists while the question is closed? So that only those who are ... (more) |
— | over 3 years ago |
| Comment | Post #279103 |
"but how can that be done in a way that says to the author "you can do [some things] and then this will be suitable here"" On the old Codidact forums, I repeatedly pushed for making all feedback to the poster who got a question closed private. The question should simply by removed from the site until... (more) |
— | over 3 years ago |
| Comment | Post #279080 |
What's the impedance of cold solder blobs? Probably not 50 ohm... also, looks like a potential short to the left on the first pic. These are some seriously cold joints. My advise is to throw this in the garbage, then make a new attempt with larger 1210 or 2512 etc, as large as you can fit. Heat the p... (more) |
— | over 3 years ago |
| Comment | Post #278984 |
I'm not so sure in general that "question invites opinions" is necessarily the fault of the question. If someone decides to write an answer which is just pure speculation, without facts, references or source, then the problem is with that answer. (more) |
— | over 3 years ago |
| Comment | Post #278984 |
It isn't really opinion-based. If I ask a question if my THR components should be replaced with SMD to save cost, then the answer is yes and it's a fact, not an opinion, and you can easily prove it by comparing the price of lets say a 100nF THR aluminium electrolyte with a 100nF SMD ceramic. Then pil... (more) |
— | over 3 years ago |
| Comment | Post #278855 |
I came across an interesting, detailed paper [here](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4884883/). So apparently microwave ovens sort under a specialized directive 2013/35/EU in the EU and also under specialized FCC Part 18 in USA. (more) |
— | over 3 years ago |
| Comment | Post #278856 |
That is, assuming that the oven and WiFi router both have FCC approval. Which I wouldn't automatically assume to be the case, some may just have "Ali Baba approval". (more) |
— | over 3 years ago |
| Comment | Post #278856 |
Bit of research about the equivalent rules in the US. https://www.fcc.gov/oet/ea/rfdevice claims that "these devices fall under the FCC rules 47 CFR Part 18". I'm not quite able to weed out which parts of Part 18 that are applicable though, §18.305 speaks of field strength of emissions for "Induction... (more) |
— | over 3 years ago |
| Comment | Post #278856 |
I read some loose rumour on the net about FCC having a special rule for microwave ovens, something about allowing 5mW in the near field, no idea if that's true (and I can't find anything about a similar rule in Europe either). However FCC part 15 generally allows a carrier of ~0.75mW ERP for short ra... (more) |
— | over 3 years ago |
| Comment | Post #278821 |
I posted a more detailed version of this question here: https://electrical.codidact.com/q/278855. Is it on-topic now? Please comment in the linked meta thread. (more) |
— | over 3 years ago |
| Comment | Post #278854 |
@msh210 I now asked a more detailed version of your question here https://electrical.codidact.com/questions/278855, just to provoke more debate and maybe get some more detailed answers. (more) |
— | over 3 years ago |
| Comment | Post #278854 |
But please note that the scope of this site is most definitely _electrical engineering_, which means design of electronics, not use of electronics, or explaining electronics to laymen. The equivalent question on for example the programming site might go like "I have this program MS Word and I notice ... (more) |
— | over 3 years ago |
| Comment | Post #278854 |
@msh210 If you can dig up the part number at least of the WiFi router and post which country you are in, then the question might be answerable. I don't know enough of microwave ovens to tell if they use different spectrums, I believe most are on 2.4GHz. But WiFi could be 900MHz, 2.4GHz (most common)... (more) |
— | over 3 years ago |
| Comment | Post #278854 |
@Kranulis In that case it was incorrectly closed, I believe. But it could be closed for the lack of detail/too broad. (more) |
— | over 3 years ago |
| Comment | Post #278834 |
If you bring up a specific post on meta, please leave a comment under that post telling that the post is being discussed, so that the OP and readers who come across it get pinged about it. I have done so now. (more) |
— | over 3 years ago |
| Comment | Post #278821 |
This post is discussed on meta [here](https://electrical.codidact.com/questions/278834). (more) |
— | over 3 years ago |
| Comment | Post #278823 |
I doubt that such an oven is legal though. Spurious emissions is typically limited to -37dBm ERP (in EU at least) and a -37dBm signal would not interfere with WiFi. (more) |
— | over 3 years ago |
| Comment | Post #278720 |
@coquelicot Well, this time estimate _has_ to be done by someone with domain experience, ideally an engineer with practical experience. I think all answers posted here come to that same conclusion. (more) |
— | over 3 years ago |
| Comment | Post #278707 |
But that customer had a fairly experienced purchaser who determined who got the contract, which isn't often the case. Still, the good customers who can call the bluff on BS offers are often the ones you want too, because they appreciate professionalism and quality. (more) |
— | over 3 years ago |
| Comment | Post #278707 |
@Adam Lawrence "if you consistently lose business because your timelines are too long". I've been through the opposite. I did a time estimate of one project and came up with something like 4 months. The competitor offered something like 1.5 months. The customer knew we were experienced, so he look ou... (more) |
— | over 3 years ago |
| Comment | Post #278654 |
@Circuit fantasist I have written lots of such posts where the true intention is rather to provide an answer to a FAQ, [example](https://software.codidact.com/questions/277486). Of course others are free to answer the question too, in case they believe they can write a better answer. Which is why it... (more) |
— | over 3 years ago |
| Comment | Post #278421 |
Here we go with the "8 bit is fantastic" war again... The 8 bitters fan club ran out of arguments well over 10 years ago. I've programmed icky 8 and 16 bitters, as well as custom 32 bitters, far more than I've programmed ARM. And that is the very reason I now avoid 8 and 16 bitters like the plague. Y... (more) |
— | over 3 years ago |
| Comment | Post #278421 |
@coquelicot Rather, _most_ microcontrollers are general-purpose ones. The vast majority of them have the same kind of common hardware peripherals: ADC, timers, PWM, UART, SPI. Traditionally, before ARM became mainstream, there were camps of devs preferring one flavour of MCUs over the other. And bef... (more) |
— | over 3 years ago |
| Comment | Post #278421 |
You can have virtual memory on microcontrollers too, on the more high end ones with MMU. But then such high end 32 bitters are about the most complex parts out there, so nothing I would recommend for beginners. (more) |
— | over 3 years ago |
| Comment | Post #278420 |
You'll have to learn about wait states, DMA etc but those are things one need to know when doing modern MCU programming. It's all MCU specific though. Again, I wouldn't recommend any particular flavour of ARM. I've worked with ST, NXP/Freescale, Microchip and Silabs ones. What you should be wary of i... (more) |
— | over 3 years ago |
| Comment | Post #278420 |
@Kranulis Depends what you mean with "step up", as in learning process? If so, then AVR is about as complex as the average 8 or 16 bitter out there. Programming some other more code efficient 16 bitter isn't that much different at all. The problem with 32 bitters isn't the core itself, but that they... (more) |
— | over 3 years ago |
| Comment | Post #278355 |
Slightly OT, but these parts absolutely hate voltage in reverse. A common design mistake with various linear regulators is to plug in an external voltage to the 5V etc plane and supplying that one from a MCU programming equipment. With no Vin present but 5V backwards on Vout, the regulator often brea... (more) |
— | over 3 years ago |
| Comment | Post #278342 |
In general, old standard logic circuits were very sensitive to ESD. Most newer parts no matter the kind has some manner of ESD protection. Still, it happens now and then that something breaks through ESD. Often the rare, mysterious kind of errors where a part breaks after some time in the field and y... (more) |
— | over 3 years ago |
| Comment | Post #278193 |
@coquelicot Is the power supply part of your product or designed by someone else? Can you modify it or buy a better one? Does it have a common-mode choke? https://en.wikipedia.org/wiki/Choke_(electronics) It usually looks exactly like the one on the top of the wiki page: a somewhat big, through-hole ... (more) |
— | over 3 years ago |
| Comment | Post #278192 |
Wouldn't you rather want a band pass filter at 100Hz +/- something? Could you give more details about the signals and application? What about currents? (more) |
— | over 3 years ago |
| Comment | Post #278161 |
(Somewhat related to that, [Rules and guidelines for drawing good schematics](https://electronics.stackexchange.com/questions/28251/rules-and-guidelines-for-drawing-good-schematics) was an awesome community wiki that I think we should consider importing here.) (more) |
— | over 3 years ago |
| Comment | Post #278161 |
One reason I asked is because such a review case popped up at electronics.stackexchange and it was closed as shopping recommendation. So it would be fine for us to send them here instead? Maybe we need to cook up some general guidelines for how to ask schematic/design review questions. (more) |
— | over 3 years ago |
| Comment | Post #278052 |
I always assumed the term discrete came from discrete mathematics, so yes...? (more) |
— | over 3 years ago |
| Comment | Post #277992 |
Not related to your question, but please note that if you don't use one of the exact approved antenna designs by the chip manufacturer, you must redo all 3rd party testing, both for RED/FCC etc and bluetooth conformance testing. (more) |
— | over 3 years ago |
| Comment | Post #277845 |
So the only thing you changed was cap chemistry, not the capacitance? What does the layout look like? THR or SMD? X5R, NP0? (more) |
— | over 3 years ago |
| Comment | Post #277541 |
Typically there is an actual register hidden beneath the addressable RAM location though, and hardware handles transitions between them. Like for example SPI will have an actual hardware shift register underneath the memory location called SPIDR. (more) |
— | over 3 years ago |
| Comment | Post #277467 |
@aditya98 433MHz can be used license free in most of Europe, Middle-East, South America, Australia and Africa. It has lots of restrictions in North America and South-East Asia, where it is typically either used for ISM or for RFID container systems. Frequency allocation world-wide is a complete mess ... (more) |
— | over 3 years ago |
| Comment | Post #276662 |
Also from what I recall, you are supposed to increase the number of parallel zener diodes depending on safety class. From what I remember, EX class 0 with intrinsically safe system requires 3 zeners. Supposedly to even out the heat between them. (more) |
— | almost 4 years ago |
| Comment | Post #276669 |
@Hawk2020 You almost certainly need a consultant - contact some test house with a good reputation for EX/ATEX. You can usually hire them for a few days to do a design review of your system and point out problematic parts. It's not just the electronics, but all mechanics, plastics etc. These kind of p... (more) |
— | almost 4 years ago |
| Comment | Post #276649 |
Why Li-Ion btw? These are very nasty from an EX perspective. NiMH or NiCd etc are much safer, although they are of course bigger and heavier. (more) |
— | almost 4 years ago |
| Comment | Post #276649 |
I don't remember, but the idea was to block current rush in case each regulator fails and de-centralize current rush protection across the board, instead of relying on one single fuse. Thermal shut-down because of overcurrent is for example not feasible. But this was also a whole lot more complex ele... (more) |
— | almost 4 years ago |
| Comment | Post #276649 |
All that matters is that you prevent current rush in case of shorts or damaged electronics, anywhere on the PCB. For example in one EX project we used 1 ohm metal film resistors in series with each regulator since such resistors were apparently considered to break in a safe manner without sparks or h... (more) |
— | almost 4 years ago |
| Comment | Post #276570 |
For EE a similar FAQ/listing/call it what you like, could perhaps be organized just like components at a silicon vendor site. "Amplifiers", "Passives", "Power management", "RF" and so on, with sub-categories. (more) |
— | almost 4 years ago |
| Comment | Post #276570 |
@Olin "It will be a long time before we can determine which ones are asked frequently" But we do have quite some experience from EE at SE. "What are decoupling caps and what value should I use", "Please help me fix this LM317", "why doesn't this simple radio circuit work well" and so on. Sounds famil... (more) |
— | almost 4 years ago |
| Comment | Post #276570 |
Ideally we'll have some on-site FAQ system eventually, but in the meantime we can use tag wikis or meta. Perhaps we should start there and write up a meta post with links to all the good stuff that's been posted in Q&A? Like "switch regulator" category, link 1 "how to design a flyback", link 2 "hummi... (more) |
— | almost 4 years ago |