10 meters effective electromagnetic field. How? - Page 1
Forum section: electronics / beginners

author: sinan
author_rank: Newbie
timestamp: January 16, 2025, 05:11:31 pm
content: I recently retired and moved to a village, but where I am staying I have a problem with cats. Especially at night, because it is hot, they go into the attic to sleep and sometimes they make noise and wake me up. I bought an ultrasonic repeller and tried it, but it did not cure the cat noise. I know the negative effect of the electromagnetic field on living things. I also know that they cannot sleep when they stay in this field. I need a solution that will cover at least 10 meters. Is that possible? If you know of a project on this subject, can you share the link? I found a video on Youtube, but I don't know if it covers 10 meters ()

author: golden_labels
author_rank: Super Contributor
timestamp: January 16, 2025, 07:05:09 pm
content: National High Magnetic Field Laboratory has one. Covers only about 5 meters,(1)but if it sucks in a ferropurrous cat, you’ll never see the beast again. Beyond that distance the cat will only get slightly tilted. Not sure, how much they charge for moving it to your house.Others will correct your beliefs below, but even without that: let’s look at what you propose. You believe that “electromagnetic field has a negative effect on living things.” So your idea is to shoot yourself and everybody around with one. You need no knowledge of physics, electronics, or maths to see something is off with the idea, do you? Rationalizing it through distance isn’t going to work. If your original premise was right, the harmful effect wouldn’t instantly drop to zero after the 10 meters mark.Fortunately it doesn’t. Neither electromagnetic field nor waves in that field have any known harmful effect on living organisms. Associating word “electromagnetic,” or just any arbitrary kind of radiation, with harm is a common misconception, and also disinformation associated with it. Not only you’re swimming in all kinds of electromagnetic radiation all the time, not only it’s crucial for survival of any known life, but at this very moment you’re emitting around 100 watts of electromagnetic radiation. At frequencies closer to carcinogenic and ionizing radiation than anything you’d ever obtain in any electric circuit.If you want to get rid of cats, consider chemical repelents likeIBI-246and similar. Combined with understanding what causes the problem: trying to limit it, or redirect cats’ attention to other places.Ultrasonic devices supposedly work, but there are two problems. First: it’s not some magical feature of ultrasonic waves, but simple noise that makes cats unwilling to be in the affected area. While higher frequencies may be less comfortable to cats, the pitch is so chosen primarily to not disturb humans. Since it’s nothing but noise, animals may either not hear it at all (hearing problems are not only a human thing), not be sensitive to it, or… adjust to it, if the incentive is high enough. The second problem is that many such devices are fakes.It also takes time for any measure to take effect. A cat will not sit in cold simply because there is something unpleasant in a warm place. It needs to have somewhere else to go. Not to mention cats are clever beasts. They learn pretty quickly to find safe spots and avoid nuisance.(1)From Veritasium:

author: Hr_Satch
author_rank: Contributor
timestamp: January 16, 2025, 07:53:55 pm
content: Haha, LoL,jup, indeed, in our nowadays -all over too technically inclined- world,we are swinging 24/7 in *radiation* under the form of electro-magnetic fields.Or you should wonder: why we receive a radio station broadcast,? only ? when we turn on our radio ?How do they do that for millions of people, LoL-- --Now about the cat thing: overhere in Europe, some are getting smarter with their relentic hunton wolves, and the why farmers, and such refuse to invest in a decent fencing, . . .=> it has been discovered that wolves, and even dogs:avoid places with big cats urine smell of Tigers, Lions, pumas, etc . . .So why not try that to get rid of surrounding cats, without any harm: just bigger cats piss ;-?To where to get a sample, that's everyones search in their living country.Haha, nice topic, Harry tha Belgian.

author: TimFox
author_rank: Super Contributor
timestamp: January 16, 2025, 07:55:07 pm
content: I never watch that type of YouTube episode, but the “vise” in the image has a useful range of less than 10 cm, to hold a steel plate for machining purposes (e.g. surface grinding) that can be released with a switch or lever.Absolutely noradiationis involved.

author: special_K
author_rank: Regular Contributor
timestamp: January 17, 2025, 01:38:22 am
content: Perhaps you can team up with the pig electrocution guy and kill cats with professor x mind rays

author: Hr_Satch
author_rank: Contributor
timestamp: January 19, 2025, 11:14:35 am
content: Dunno, how pungent Big Cats scent smells around a house, LoL ;-?But it sure is green, as to no energy required,works even when cloudy and no wind

author: Sorama
author_rank: Frequent Contributor
timestamp: January 19, 2025, 11:50:21 am
content: A simple and effective solution would be to close all the openings to the attic.Can’t be that difficult as an attic should be airtight by default.

author: Haenk
author_rank: Super Contributor
timestamp: January 21, 2025, 11:53:12 am
content: My wife bought a cat repeller: A watergun with selenoid, actived by PIR sensor. Place that near the entry point, and I assume most cats will not pass.Other than that, cats are clever and will ignore most disturbances.

author: Siwastaja
author_rank: Super Contributor
timestamp: January 21, 2025, 12:15:02 pm
content: Quote from: Haenk on January 21, 2025, 11:53:12 amEven simpler: close the entry point.

author: Xena E
author_rank: Frequent Contributor
timestamp: January 21, 2025, 01:00:59 pm
content: I'm not going to even acknowledge the EMF, wo wo nonsense, but just leave citrus peel where you dont want cats!(Grapefruit skin zest is best).X

author: Haenk
author_rank: Super Contributor
timestamp: January 23, 2025, 10:29:33 am
content: Quote from: Xena E on January 21, 2025, 01:00:59 pmI bet our cat would just try to eat it

author: valcher
author_rank: Contributor
timestamp: January 23, 2025, 12:43:12 pm
content: Cats really love the smell of valerian root, maybe you have some drying in your attic?

author: Terry Bites
author_rank: Super Contributor
timestamp: January 23, 2025, 04:39:35 pm
content: Fix your attic?