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Thread ID: 141969	2016-04-03 22:41:00	Can a compass be affected (permanently) by a microwave oven?	John H (8)	PC World Chat

Post ID	Timestamp	Content	User
1418585	2016-04-05 20:24:00	To put it succinctly, the rediculum larportium influence is to blame. Eg when a compass negates the flaturecence or bugaratule affect it compromises how Mars interfaces with our Moon, therefore sending pistronic waves to our polar regions, which in turn reverses all incoming bratocular impulses. A good example is how a simple farmyard hen always knows where her eggs lay... does she actually know where, how or when they land up in the pot? Well that of course is a good thing cos if she did, we'd end up with half scalded chooks :eek: How do you think they got the inspiration for hot pants? ;)	R2x1 (4628)
1418586	2016-04-05 23:05:00	When the earths mag feild flips , it will be everyone in the US standing on there heads . Perhaps thats starting to happen up there ? Would that explain Mr Trump ? My advice, buy a nice soft pillow in advance...and dont try & make a bamboo pillow yourself. DIY bamboo pillows are a bit painfull. The earths mag field flip is coming, as predicted by the ramblings of Nostradamus's latest DVD, available on itunes.	1101 (13337)
1418587	2016-04-05 23:12:00	Well.... I'm a-political - but I do enjoy a good show!	SurferJoe46 (51)
1418588	2016-04-06 02:29:00	Well.... I'm a-political - but I do enjoy a good show! At least theres now alot of interest in the process , even over here . And possibly more will get out to vote just keep certain hated candidates out (from both parties) , or put them into Office :-)	1101 (13337)
1418589	2016-04-06 02:58:00	Like Bill Clinton told the illegals in California: "Vote early .............. and vote often".	SurferJoe46 (51)
1418590	2016-04-07 00:34:00	It is unlikely that the static field emitted from the magnetron would cause a compass to change polarity, because although it is very powerful, that energy is focussed in the cavity. Also, the compass would always align with the opposite polarity (like poles repel, opposite poles attract) which would maintain its correct polarity. Conversely, a more likely cause is the power transformer, because the 'thung' noise you hear when starting a microwave is the inrush current causing a powerful magnetic pulse alternating at 50Hz. There are positive and negative half cycles, so the output is at 100 Hz and it is a very effective demagnetiser. However, when it is switched off, if that happens at the peak of the current cycle then the collapsing field could easily demagnetise a compass or change its apparent polarity. Cheers Billy 8-{) At least there is one sane voice out there! Thanks very much for that, Billy. It all makes sense.	Roscoe (6288)
1418591	2016-04-07 02:17:00	It is unlikely that the static field emitted from the magnetron would cause a compass to change polarity, because although it is very powerful, that energy is focussed in the cavity . Also, the compass would always align with the opposite polarity (like poles repel, opposite poles attract) which would maintain its correct polarity . Conversely, a more likely cause is the power transformer, because the 'thung' noise you hear when starting a microwave is the inrush current causing a powerful magnetic pulse alternating at 50Hz . There are positive and negative half cycles, so the output is at 100 Hz and it is a very effective demagnetiser . However, when it is switched off, if that happens at the peak of the current cycle then the collapsing field could easily demagnetise a compass or change its apparent polarity . Cheers Billy 8-{) C/P from THE INTERNET - so it must be true . . . . . . Microwave ovens emit two kinds of EM radiation – microwaves (which leak past the seals and through the screen) and low-frequency radiation (50/60 Hz), which is emitted primarily by the electrical transformer used to power the magnetron, and cannot be shielded by the casing of the oven . and . . . . . . . . . Microwaves are among the household appliances that tend to produce powerful low-frequency magnetic fields . However, the burden of the magnetic fields caused by such appliances is relatively low since they are only ever operated for a short time . The studies carried out to date have not produced reliable evidence that microwave ovens have any effect on health I have a Simpson Roll Top Analog meter and a galvanometer attachment (just a simple multi-strand coil of copper wire in about a 12 inch loop) that I pulled out of storage from under my bed and bought new batteries for it for just this test . Under my microwave, turning it On, Off, High Power, Defrost Cycle, etc, there is NO magnetic activity that I can measure under, over, near or around any part of my microwave . I humbly question if magnetic 'waves' or 'impulses', 'pulses' or 'cyclical surges' can pass through the case of the microwave at all . I imagine that this depends on the axis of the transformer, since turned one way it might send a magnetic 'wave' out the bottom, whereas if it were turned 90 degrees, it would 'fire' the same magnetic effect into a different axis/plane/attitude . I know I'm gonna get called out on a technicality here with so many erudite* and intelligentized, electronical-types, but I had a tiny smidgen of experience with magnetrons during the time I worked as a Biomedical Engineer at a medium sized Los Angeles hospital . Hence the old electrical testing stuff . That (above ^) being a hospital environment, we were not allowed any measurable unwanted radiation ---- of any kind - no matter where or what or when . Just a thought . * erudite: " … terminally droll, and a wizard phrasemaker . " —Susan Sontag, New Yorker, 18 & 25 June 2001 Oooooh! I think that's my new sig!	SurferJoe46 (51)
1418592	2016-04-07 09:36:00	[QUOTE=SurferJoe46;1242961] I have a Simpson Roll Top Analog meter and a galvanometer attachment (just a simple multi-strand coil of copper wire in about a 12 inch loop) that I pulled out of storage from under my bed and bought new batteries for it for just this test. Under my microwave, turning it On, Off, High Power, Defrost Cycle, etc, there is NO magnetic activity that I can measure under, over, near or around any part of my microwave. [/] Well SJ, I hate to say it, but as described, your equipment is the equivalent of a horse and buggy at a Formula One race track. If it cannot detect the ELF field from the transformer, or even from the turntable motor, it is as much use as water pistol at a Hi-Rise Apartment fire. I mean no disrespect, but the equipment you describe is laughably insensitive and therefore inadequate, hence your failure to detect alternating electro-magnetic field activity. Now for some facts: You need triaxial pickup coils and 60Hz detection sensitivity [50Hz here in Godzone] down to 100nT or less, plus a peak reading capability of 100 microtesla or more. Our small microwave oven radiates an ELF field of up to 100+ microtesla RMS around the circumference of the cabinet, with peaks occurring when adjacent to the transformer location within the cabinet. [ELF = 20Hz-2000Hz] Although in theory the microwave should not radiate VLF, in fact it does do so because of the radiated harmonics created by the power management system [VLF = 2kHz to 400kHz] and I measured 150nT at the side of the cabinet. The above figures are typical of the average small domestic microwave oven, but might be significantly higher from a larger domestic oven with more sophisticated power management. The instruments used to measure field strength were from Combinova of Sweden, who have a reputation for producing high quality test equipment. Their measurement capability is triaxial and true RMS. Now, getting back to the facts, there is more than enough radiated ELF energy from a small microwave oven to flip a compass during the ac cycle, and if switch-mode microwave power regulation is employed, then there will be additional harmonics to enhance those effects. In my opinion the case is made: "Under appropriate circumstances, a microwave oven can cause polarity reversal in a compass but the cause is not the microwaves, or the magnetron, but the radiated ELF field from the power transformer and possibly associated ELF radiation from any power management system." It is the coincidence of both location and timing that will reverse the polarity of the compass needle, and it might prove difficult to repeat the process. Stroking the compass needle with a strong ferrite magnet (after first establishing the correct polarity i.e. the magnet repels the pole you start with) but it is much easier to buy a new compass and keep it well away from your microwave oven. QED Cheers Billy 8-{) :thumbs:	Billy T (70)
1418593	2016-04-07 15:59:00	I recognize(d) that I'm using predeluvian technology, and your kindness in gently mentioning that fact, exceeded my base expectations . All in all, I find this exercise in resuscitation of a compass as enlightening and certainly not without merit . Had the compass of mention been a family heirloom or of scientific need, like an engineer's or survey tool, I too would have been chagrined to find it pointing to the next magnetic north location, this time right after the earth killing asteroid snuffs life out on earth . But knowing that the only surviving life form after that collision would be the giant burrowing cockroach (Macropanesthia rhinoceros), I know they'd have little interest in a compass no matter the intrinsically human evaluation placed upon it by a (then-) vanquished bipedal race . Thank you for the info, simply put . I found it very enlightening and enjoyable .	SurferJoe46 (51)
1418594	2016-04-07 22:20:00	Would a simple test be to place the compass near the microwave, turn it on & see if the compass needle moves ? If theres enough of a magnetic feild to flip the compasses mag polarity, would that also be enough to move the compass needle ? and vice versa	1101 (13337)
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