RE: Radio Free GMR
At 12:00 am 26/11/2005 -0500, you wrote: Now Mr. WholeHam, if you're not nice I might do a search on the vortex list and see who else uses some of the unique features of your posts... I am legion, of course, or so it seems to the internet. Talking of searches, I was interested to find that a hohlraum is a piece of scientific equipment. Definition of hohlraum A laboratory device to produce blackbody radiation. Consists of a closed metal tube, blackened on the inside, with a narrow slit cut into one of the flat ends. On heating the tube the radiation escaping from the slit is virtually identical with that expected from a blackbody. One learns something new every day on Vortex 8-) Frank Grimer
Re: Radio Free GMR
That's me, hollow cavity with a hole in my head. -Original Message- From: Grimer [EMAIL PROTECTED] Talking of searches, I was interested to find that a hohlraum is a piece of scientific equipment. Definition of hohlraum A laboratory device to produce blackbody radiation. Consists of a closed metal tube, blackened on the inside, with a narrow slit cut into one of the flat ends. On heating the tube the radiation escaping from the slit is virtually identical with that expected from a blackbody. One learns something new every day on Vortex 8-) Frank Grimer ___ Try the New Netscape Mail Today! Virtually Spam-Free | More Storage | Import Your Contact List http://mail.netscape.com
Re: Radio Free GMR
On Fri, 25 Nov 2005, Nick Reiter wrote: Is anyone aware of a source of white noise in electronic circuits that is related to either magnetic domain or electron spin polarization? (Or de-polarization?) Barkhausen noise. Caused by the walls of magnetic domains suddenly becoming un-pinned and jumping to new shapes. It also appears on a transformer secondary when you apply slowly-varying DC to the primary. Also, some of the early radio detectors (from the pre-tube era) were based on this, where a motorized loop of thin iron wire was passed between pole pieces and the RF influenced the hiss and made a sort of pulsewidth modulated audio. It was also claimed to be a source of FE by these guys years ago: http://amasci.com/freenrg/bark.html http://jlnlabs.imars.com/spgen/barkhausen.htm Here's another which, if real, must be from Barkhausen effect: http://my.voyager.net/~jrrandall/CookCoil.htm I've been playing with non- or micro-inductive coils made from ferromagnetic materials (nickel wire mainly) and I've found a neat effect that manifests as a burst of strong hissy white noise whooshing when a large magnet is moved by hand toward the coil. Try using pieces of steel shim foil, or of transformer lamination. The noise seems to depend on how many pieces you stack up (with thin sheets giving fewer but louder clicks.) I've heard that metglas gives weird results but haven't tried it. And years ago there was a company selling single-domain iron fibers which would give huge pulses when the field hit a certain threshold and caused the entire fiber to switch. Still, I've been thinking along the lines of spin-spin communication, If a domain wall is getting stressed by a rising field and is about to flip, perhaps non-magnetic signals can determine when the click happens. If so, then Barkhausen radio detectors might also pick up non-EM signals. (( ( ( ( ((O)) ) ) ) ))) William J. BeatySCIENCE HOBBYIST website billb at amasci com http://amasci.com EE/programmer/sci-exhibits amateur science, hobby projects, sci fair Seattle, WA 206-789-0775unusual phenomena, tesla coils, weird sci
RE: Radio Free GMR
Hi Nick, That'd be called barkhausen noise; a magnetic effect even your dog can pronounce. The wooshing is caused by the unpinning of domain walls, if you look carefully at the signal with a scope you can see the individual avalanches of domain motion. Try it with various samples of transformer iron, I'm sure you can find certain samples that will show the effect very strongly. Your bahhh instinct is correct, the effect was discovered in 1919. Google on that keyword for more information, and consult your Bozorth for details. You do have a copy of Bozorth, huh? Well buy a used one, for bogs sake! Indispensible ref for things magnetic. K. -Original Message- From: Nick Reiter [mailto:[EMAIL PROTECTED] Sent: Friday, November 25, 2005 4:28 PM To: vortex-l@eskimo.com Subject: Radio Free GMR ...or what is the sound of one electron flipping? Rather than go into a long winded preface describing the circumstances of a curious little effect I have been listening to lately, let me toss this out to the scholars of electrons. Is anyone aware of a source of white noise in electronic circuits that is related to either magnetic domain or electron spin polarization? (Or de-polarization?) I've been playing with non- or micro-inductive coils made from ferromagnetic materials (nickel wire mainly) and I've found a neat effect that manifests as a burst of strong hissy white noise whooshing when a large magnet is moved by hand toward the coil. To get a second whoosh , I have to pull the magnet away, flip it over to the opposite polarity, and then push it toward the coil again. As if the burst of white noise comes from domains being de-polarized and re-polarized... hysteresis noise? Replicating the actions with an identical coil made from copper wire produces no such effect at all. Just starting to play wit' dis' one, so my reports may be sporadic here. My ba nature says that this must be something well known, but I've never run into it before. Still, I've been thinking along the lines of spin-spin communication, and more pragmatically, spin polarized radio. I've been trying to bone up on GMR and spin valve materials technology. Maybe there is some connection here? NR __ Yahoo! Music Unlimited Access over 1 million songs. Try it free. http://music.yahoo.com/unlimited/
Re: Radio Free GMR
On 25 Nov 2005 at 13:27, Nick Reiter wrote: Just starting to play wit' dis' one, so my reports may be sporadic here. My ba nature says that this must be something well known, but I've never run into it before. Barkhausen noise perhaps: http://jlnlabs.imars.com/spgen/barkhausen.htm Mark Jordan
RE: Radio Free GMR
Aha! OK, well, that name rings a bell! I'll study up on it a bit. Muchas gracias, mein cheese... When I began to play with this last week, one thing that came back to mind was a really neato article that I remember reading in an ancient issue of CQ (or maybe QST) from somewhere in the early 1960s. (An old ham down the road from me had given me a pile of these when I was a kid - wonderful reading) Anyway, it was an article by a radio engineer named Jerzy Ostermund Tor (spelling approximate). This fellow had developed a two way radio technique using the magnetosphere as the modulated medium, and double loop ferrous antennae for tx and rx. It was called MEMTAC. Have never seen anything on thatin the literature since. Might have been a ruse, dunno; or perhaps died with the inventor before being developed. Still, I wonder if somewhere in Barkhausen noise might lurk something useful. Maybe magnetotactic bacteria could be made to speak up! N --- Keith Nagel [EMAIL PROTECTED] wrote: Hi Nick, That'd be called barkhausen noise; a magnetic effect even your dog can pronounce. The wooshing is caused by the unpinning of domain walls, if you look carefully at the signal with a scope you can see the individual avalanches of domain motion. Try it with various samples of transformer iron, I'm sure you can find certain samples that will show the effect very strongly. Your bahhh instinct is correct, the effect was discovered in 1919. Google on that keyword for more information, and consult your Bozorth for details. You do have a copy of Bozorth, huh? Well buy a used one, for bogs sake! Indispensible ref for things magnetic. K. -Original Message- From: Nick Reiter [mailto:[EMAIL PROTECTED] Sent: Friday, November 25, 2005 4:28 PM To: vortex-l@eskimo.com Subject: Radio Free GMR ...or what is the sound of one electron flipping? Rather than go into a long winded preface describing the circumstances of a curious little effect I have been listening to lately, let me toss this out to the scholars of electrons. Is anyone aware of a source of white noise in electronic circuits that is related to either magnetic domain or electron spin polarization? (Or de-polarization?) I've been playing with non- or micro-inductive coils made from ferromagnetic materials (nickel wire mainly) and I've found a neat effect that manifests as a burst of strong hissy white noise whooshing when a large magnet is moved by hand toward the coil. To get a second whoosh , I have to pull the magnet away, flip it over to the opposite polarity, and then push it toward the coil again. As if the burst of white noise comes from domains being de-polarized and re-polarized... hysteresis noise? Replicating the actions with an identical coil made from copper wire produces no such effect at all. Just starting to play wit' dis' one, so my reports may be sporadic here. My ba nature says that this must be something well known, but I've never run into it before. Still, I've been thinking along the lines of spin-spin communication, and more pragmatically, spin polarized radio. I've been trying to bone up on GMR and spin valve materials technology. Maybe there is some connection here? NR __ Yahoo! Music Unlimited Access over 1 million songs. Try it free. http://music.yahoo.com/unlimited/ __ Yahoo! Mail - PC Magazine Editors' Choice 2005 http://mail.yahoo.com
Re: Radio Free GMR
Hans Coler allegedly made a FE generator which self-synchronized these random domain shifts in ferromagnetism. Fairly reliable documentation supports these claims: http://www.rexresearch.com/coler/colerb~1.htm http://www.angelfire.com/ak5/energy21/hanscoler.htm The second reference, while incomplete, offers a beautiful image of an attempted replication. Dr. Harold Aspden offers an explanation: http://www.energyscience.org.uk/le/le07.htm -Original Message- From: Nick Reiter [EMAIL PROTECTED] Is anyone aware of a source of white noise in electronic circuits that is related to either magnetic domain or electron spin polarization? ___ Try the New Netscape Mail Today! Virtually Spam-Free | More Storage | Import Your Contact List http://mail.netscape.com
Re: Radio Free GMR
Interesting, Ms. Nagel. Or is it Mr. Nagel? Your Yahoo profile says you're female, but I have not met many Keith girls. veg http://profiles.yahoo.com/horselover_fats We need more F's in FE! I find the Wiegand Wires (WW) interesting. I'll study the references more. Do you think the WW impulses tap the ZPF? -Original Message- From: Keith Nagel [EMAIL PROTECTED] One can synchronize the jumps by playing games with the underlying material, check out wiegand wires for more information about one such implementation. I wouldn't be expecting to power my house with this just yet though...(grin) K. ___ Try the New Netscape Mail Today! Virtually Spam-Free | More Storage | Import Your Contact List http://mail.netscape.com
RE: Radio Free GMR
Now Mr. WholeHam, if you're not nice I might do a search on the vortex list and see who else uses some of the unique features of your posts... I am legion, of course, or so it seems to the internet. I think wiegand wires can be viewed as macroscopic domains. You'll have to explain what tap the ZPF means though. K. -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Sent: Friday, November 25, 2005 11:07 PM To: vortex-l@eskimo.com Subject: Re: Radio Free GMR Interesting, Ms. Nagel. Or is it Mr. Nagel? Your Yahoo profile says you're female, but I have not met many Keith girls. veg http://profiles.yahoo.com/horselover_fats We need more F's in FE! I find the Wiegand Wires (WW) interesting. I'll study the references more. Do you think the WW impulses tap the ZPF? -Original Message- From: Keith Nagel [EMAIL PROTECTED] One can synchronize the jumps by playing games with the underlying material, check out wiegand wires for more information about one such implementation. I wouldn't be expecting to power my house with this just yet though...(grin) K. ___ Try the New Netscape Mail Today! Virtually Spam-Free | More Storage | Import Your Contact List http://mail.netscape.com
