Stupid Induction cooking TECHNICAL question

Discussion in 'Fred's House of Pancakes' started by cyberpriusII, Aug 9, 2016.

  1. cyberpriusII

    cyberpriusII Prodigyplace says I'm Super Kris

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    Hmm, this might be better for the Martha Stewart site, but actually not.

    I have an induction (magnet) cooktop. I love it, especially being that I am at highish altitude and it gets water boiling quickly.

    But, it does a number when I try to cook and listen to AM radio. FM radio is no problem. What I mean is the AM broadcast is reduced to gurgles and warbles and stuff. FM remains clean.

    Can someone here explain it -- in MY terms -- why the diff. Hey, I am a curious sort....
     
  2. ILuvMyPriusToo

    ILuvMyPriusToo Senior Member

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    Probably so few folks listen to AM anymore that this may never have been reported. :eek:

    Probably just electromagnetic noise on those frequencies.
     
  3. cyberpriusII

    cyberpriusII Prodigyplace says I'm Super Kris

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    Yeah, so, I figured some sort thing along that line, which I really do not understand (my field is biology and believe it or not I actually got a third-rate university to issue a PhD.), But, so, is there an easy, quick thing that even I could understand that would explain why one radio wave is different....gosh, I think I actually stepped into a sinkhole. If so, everyone, stop me now.

    BTW, this is all just a decoy to get Bisco to forget about Russian women (and, yes, that is a lame inside joke).
     
  4. Eastside

    Eastside Member

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    Some cookers have an FCC license and the instruction manual should warn about the possible interference.

    Some induction cookers generate radio frequencies, for example 400k cycles. AM radio is 540k -1600K cycles.

    Those cookers act like a radio transmitter running at 400k cycles; and the harmonics at 800k, 1200k, and 1600k can be "heard" by a nearby AM radio.

    Here is LG's note: " . . . This unit generates, uses and can radiate radio frequency energy and, if not installed and used in
    accordance with the instructions, may cause harmful interference to radio communications. "
     
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  5. cyberpriusII

    cyberpriusII Prodigyplace says I'm Super Kris

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    Eastside. Thank you! That makes sense. The station I normally listen to on AM is 550. So, while the details still remain a bit sketchy in my feeble brain, I think I understand it a bit more.Just means when I cook I will listen to the local KRVM station and be free of gurgles!

    BTW, my other vehicle is a DiamondBack!
    KRIS!
     
  6. tochatihu

    tochatihu Senior Member

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    Induction cooker can be viewed as a very poorly designed radio transmitter. Radiating at about 1/40 the frequency of AM radio, but not tuned to a narrow frequency.

    AM receiver makes 'noise' based on how much signal strength varies in the frequency (range) it is listening to. With an induction cooker nearby, this is a lot.

    FM receiver makes 'noise' based on how much the strong signal in its frequency (range) varies in frequency. Not getting bigger or smaller; moving around. That, and the fact that it listens at about 100 times higher frequency than AM, cause the difference.

    Sadly the question was posed not concerning how a crappy radio transmitter heats some cooking pans and not others. That is more fun. Even more fun are Maxwell's equations and how they came to be, So if you are as curious as claimed...
     
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  7. ILuvMyPriusToo

    ILuvMyPriusToo Senior Member

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  8. xliderider

    xliderider Senior Member

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  9. Tideland Prius

    Tideland Prius Moderator of the North
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    Eastside's pretty much got it.

    Basically a radio works by having a receiver inside the radio that can receive waves of certain frequency. It doesn't care what the source is. Your induction cooktop works by passing electricity through coils. That generates a magnetic field. It's the magnetic field that interacts with the cast iron or stainless steel cookware that causes the pan to heat up.

    Anyway, because you're passing AC current, you're generating a rapidly alternating magnetic field too. So any time you're alternating something, you're essentially creating a wave. If the wave happens to have the same frequency as your receiver, then your receiver will pick it up as noise.
     
  10. ChapmanF

    ChapmanF Senior Member

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    Wow ... that's not a stupid question. It might be a great example of the kind of question that's just hard to give a good lay answer to, though.

    Probably as good as it gets at the shallow end is to say something like "when you send a signal over an electromagnetic wave, you can use the signal to modulate the wave's amplitude (AM), or to modulate the wave's frequency (FM) ... those aren't the only two choices, but they're the common ones. At the other end, the receiver will be picking up the wave you sent, mixed in with all the other waves coming from induction cookers, hair dryers, other radio stations, fluorescent lights, etc., and the receiver has an easier time picking your original signal back out of that mess if you sent it by modulating the frequency, than by modulating the amplitude."

    But even an answer like that probably only makes you say one of two things:
    • Ok, Chap's just snowing me with a bunch of jargon here, and he might as well just have waved his hands and said "it's magic, deal with it."
    • Hmm, I guess I remember what amplitude and frequency meant for waves, and I wonder what it means to 'modulate' one or the other, and assuming I find a good explanation of that, then what's the explanation why modulating one makes it easier to extract the original signal than modulating the other??

    ... and if you take my answer the first way, I really haven't answered anything, and if you take it the second way, then in no time you'll be in places like this and this.

    I'm not sure there's really any good middle ground. This link seems like it's trying to say something while staying less technical, but I'm not sure it works. At some point, there's still the question "ok, what did any of that actually mean?" and the answer either looks like math, or is just more handwaving.

    So it ends up pretty much with a comment I still enjoy, written in my college electronics lab notebook by Prof. Thomas, after a question I had left in my lab report:
    bruce.png
    Sadly, I was taking Electronics my senior year, and never did have the chance to take Waves from him. (Edit: wouldn't have been from him anyway ... Prof. Casper was teaching Waves then.)

    -Chap
     
    #10 ChapmanF, Aug 9, 2016
    Last edited: Aug 9, 2016
  11. cyberpriusII

    cyberpriusII Prodigyplace says I'm Super Kris

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    O.K.:

    I do have a ligament issue with my foot, which is keeping me close to chairs. So, after looking at all that you folks have written and cited, and looking at it all a second time (yes, it took a second time), I think I understand it as well as I ever will (not all that complicated unless you really want to dig in).

    So, I sincerely thank each of you for your answers. It had just been a bit of a pain each evening as I began to get dinner going and the local station began to go south at the same time. So, now, while I still have the same issue, at least I understand it and I have made the FM station my new friend.

    Thanks, again,
    kris.
     
  12. tochatihu

    tochatihu Senior Member

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    Not the first time I've failed to interest civilians in wonders of Maxwell's equations. Too bad - he clearly merits membership in the big three (+Newton +Einstein) and arguably the nicest human among them. Newton being contrary example:)

    Many (lower bod) ligament injuries heal way to slow because victims cannot be dissuaded from hobbling about and doing further damage. This is your most poorly vascularized tissue, thus slow to heal. Sadly, females seem less likely to use canes or crutches. Vanity I suppose. Don't be that girl.
     
  13. cyberpriusII

    cyberpriusII Prodigyplace says I'm Super Kris

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    Tochatihu:

    Wow, I appreciate the fact that you posted back. Indeed, while I admit to skimming over the original post, since you made an effort, I will also!. I appreciate your concern.

    I actually injured the same foot about 18 months ago and forbid to walk on it for about six weeks. Saturday I was in a triathlon and injured it again, although not as seriously. But, yep, again, I am moping.

    Anyway, thanks again. I will look into your suggestion!
    kris
     
  14. tochatihu

    tochatihu Senior Member

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    Stay off the damn thing. You are balancing "I'm so sporty" validation now against 'good enough' mobility in later years. Young people are famous for making such choices poorly.
     
  15. ETC(SS)

    ETC(SS) The OTHER One Percenter.....

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    +1

    When I was in Submarines, we were mostly 3-milers.
    The Navy made us run 1.5 miles for our Performance Readiness Test....or PRT, every 6 months.......when we didn't gun-deck the paperwork.
    The longest ship in the Navy is less than 1/4 mile in length, and the dirt sailors are taught how to shoot fairly well, so running is a pointless endevor, IMHO.
    We literally had one sailor that was trying to stay in with a BMI deep into the 30's, a real 'hatch plug."
    The standards were so lax back then (when we adhered to them) that we had one Chief actually fast-walk the "run" portion of the PRT while smoking an unfiltered Camel...........and get a passing score.
    Those were the days!!!!

    Then?
    A bunch of diet and exercise nerds took over my beloved Navy AND I had the misfortune or fortune---depending on the year, of becoming a reservist.
    GOD's sense of humor at work.
    Since there is no such thing as a reserve submariner, I had to trade in my tactical sneakers for combat boots and my poopie suits for some nice, earth-toned wardrobe........and I had to %^#[email protected]#[email protected]! run.
    3 miles.
    In one day......
    Every %^%$^@@@ day I was on duty.

    Needless to say, as I advanced in years, some of my joints started grumbling and complaining as loudly as I did on my morning runs.

    Unless you're being chased?
    Running isn't a good mode of transportation. The only thing worse are the gym rats that blow out their shoulders at 30 years by trying to lift outside their depth band.

    Lay off the endorphins for a while... :D

    Good Luck!
     
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