Activity for Lundin
| Type | On... | Excerpt | Status | Date |
|---|---|---|---|---|
| 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 |
| Edit | Post #278886 |
Post edited: typo |
— | over 3 years ago |
| Edit | Post #278886 |
Post edited: |
— | over 3 years ago |
| Edit | Post #278886 | Initial revision | — | over 3 years ago |
| Answer | — |
A: Why is the ACK (acknowledge bit) in the CAN bus frames dominant? What could have been the rationale behind that design decision? You are forgetting that the transmitter plays part of it too. ACK is dominant simply because the transmitter sends ACK as recessive and any receiver must be able to override the recessive state of the transmitter's ACK bit. There's no "three state" or such available to the transmitter. CAN works l... (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 |
| Edit | Post #278854 |
Post edited: |
— | 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 |
| Edit | Post #278854 |
Post edited: |
— | over 3 years ago |
| Edit | Post #278855 | Initial revision | — | over 3 years ago |
| Question | — |
Microwave oven interfering with WiFi on the 2.4GHz band As I understand it, microwave oven magnetrons operate at 2.45GHz, which is an unlicensed band in most of the world. When 2.4GHz technologies such as WiFi (802.11), Bluetooth and Zigbee were launched, there were concerns that these would collide with microwave oven frequences. I remember a very early ... (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 |
| Edit | Post #278854 | Initial revision | — | over 3 years ago |
| Answer | — |
A: Why are posts that users clearly approve of being closed? The current applicable rule from https://electrical.codidact.com/help/topics would be: > Off-topic > ... > High-level use of electrical devices. > > If your question treats a device like a black box and isn't about its theory of operation or its design tradeoffs, then it's likely off topi... (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 |
| Edit | Post #278720 | Initial revision | — | over 3 years ago |
| Answer | — |
A: How to estimate time of completion while developing an electronic product? First of all, it depends on how much work the customer has done in advance. Do they have a proper spec? Do they at least have a bunch of key requirements? Or is it just "out there" and you must drag the spec out of the customer through interrogation and mind reading? If there isn't a proper spec, ... (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 |
| Edit | Post #278654 |
Post edited: |
— | over 3 years ago |
| Edit | Post #278654 | Initial revision | — | over 3 years ago |
| Answer | — |
A: Can I ask a question to which I have a possible answer? The key to writing good self-answered Q&A is to try to write the question just as if you didn't know the answer. That is, it has to fulfil the usual quality criteria for normal questions. This can be quite hard! My best advise is probably to give a specific example in the question. For example pos... (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 |
| Edit | Post #278420 |
Post edited: |
— | over 3 years ago |
| Edit | Post #278420 | Initial revision | — | over 3 years ago |
| Answer | — |
A: I have to choose: Arduino or Raspberry pi. - Rasp PI is a PC in disguise - it is a single-board computer. As such it runs Linux and like any Linux PC, it doesn't allow real-time execution, direct access to physical addresses, deterministic single-process execution etc etc. Writing drivers yourself is a complex process where you must foll... (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 |
| Edit | Post #278136 | Initial revision | — | over 3 years ago |
| Question | — |
Are BOM cost optimization questions on-topic? Are BOM/PCB assembly cost cost optimization questions on-topic here? I can see how chasing down specific parts, prices and vendors ought to be off-topic, so I don't mean outright shopping/second source recommendations. But I rather mean a design review of the schematic as whole, to suggest ch... (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 |
| Edit | Post #277912 |
Post edited: |
— | over 3 years ago |