Calculate Resonant Frequency Large Loop Coil

If it's supposed to be the Schumann resonance, that frequency wanders aroun d. Why use a fixed, non-tunable coil?

Is this a detector? Or an electromagnet? If a detector, are you sure you d on't just want a search-coil, a sensor-loop? Then either tune it with capa citances connected in parallel, or just amplify the output and handle the r eceived signal in electronics (bandpass, etc.)

If it's to be an electromagnet *generating* a b-field, then resonance isn't the critical factor for producing a large field. Instead, wattage is the limiting number, and you'd want to know the field produced when you're *not

• frying the coil. For the hoop-size you're using, a hundred watts might he at it quite a bit, giving ~700 amp-turns from the values below. Doesn't ma tter whether it's resonant or not, since the power supply still has to prov ide the hundred watts regardless. Also, doubling the total copper will dou ble the field strength, if operated at constant max wattage.

Completely fill your conduit, and *probably* the resonant frequency will st ill be far, far higher than 8Hz. (Where did your 30ga size come from? Are you certain it's not supposed to be much smaller?)

First calculate the lbs of #30 wire needed to fill up your plastic form ent irely. Something like 90turns/layer, 60layers, 20lbs or so, roughly 6000 t urns? 62,000 feet, 6,400ohms.

So, wind 10lbs onto the hoop, and measure the self-resonance. You'll then know if you're in the ballpark, or instead will you need hundreds of lbs?

Anybody have a 10lbs spool of #30?

Leave it on the spool, dig out the inner end, and see if you can measure inductance and self-resonance!

:)

If it's many orders of magnitude away from 8Hz, then dumping 10lbs spool onto a 1 meter hoop-coil won't get you down far enough.

Oops. I guessed wrong. Heartmath has their own monitoring station. See Fig 11.2 at: Looks like a magnetometer. Photos of a monitoring site under construction:

Actually, I'm surprised that they still use numbers. Numbers are so confining and rigid. To really become one with the global consciousness, one must shed all such mechanistic approaches to reality and simply "feel" the fields. Of course, since feelings are subjective and have no units of measure, they would be difficult to quantify.

Note: I'm trying to delay climbing onto my roof and applying a gallon of wet patch to where I suspect the leaks have moved. The above is the best I could conjure under the circumstances.

Yep, although I didn't realize they were that weak. The Wikipedia article suggests 10^-7 weaker: "Similarly, the amplitude of the Schumann resonance magnetic field (~1 picotesla) is many orders of magnitude smaller than the Earth's magnetic field (~30-50 microteslas)"

One of the articles wiggles out of that problem by suggesting that:

"A growing body of data also suggests that changes occur in ionospheric activity before earthquake activity." - Uyeda, S., et al., Geoelectric potential changes: possible precursors to earthquakes in Japan. Proc Natl Acad Sci U S A, 2000. 97(9): p. 4561-6. - Kopytenko, Yu A., et al. "Detection of ultra-low-frequency emissions connected with the Spitak earthquake and its aftershock activity, based on geomagnetic pulsations data at Dusheti and Vardzia observatories." Physics of the Earth and Planetary Interiors 77.1(1993): p. 85-95

Instead of a source of error, the changes in the field magically become a precursor, thus purifying the data.

Argh. Time to patch the roof. If you don't hear from me, I fell off the roof.

My god, I scanned that page quickly, but I feel dumber already.

That means that you are not connected to the global consciousness (also known as "the force") and need to have your brain retuned to the proper Schumann frequencies so that it may resonate with all the others trying to harmonize their thoughts. This is normally done by inhaling, ingested, or injecting various controlled substances, but can also be accomplished by merely beating ones head against the wall. Note that the enlightenment and visions achieved are only temporary.

Ok, break is over and back to reality. Onto the roof I go with another half-gallon of wet patch. Beating my head against the wall might be more fun. Grumble...

Thanks Bill. That is all good advice.

I was looking into making the output coil resonant because I could then use it interchangeably as an input (detection) coil. I thought it might be easier to fabricate than a solenoid which requires a lot more wire for a similar frequency response.

BTW the 8Hz resonant solenoids I already have only weigh about 5Kg with their Mu cores fitted.

Resistance is 19K. I resonate them with a 4.7uF cap to center on 8Hz. That's a "conventional" setup for geomagnetic monitoring.

Kevin Foster

I suspect they are using it to predict the stock market.

Kevin Foster

Uh, Bill, it seems like a square law to me.

but doubling the field strength quadruples the power consumption.

Doubling both the cross-section and the length of the wire gets you a coil with 4 times as much copper, twice as many turns, four times the inductance, and the same DC resistance and as the original.

What's an order of magnitude between friends?

Preshock?

Don't track that iccky black goo inside.

This is our leak:

I chased it all around the ceiling with a sabre saw, until I found the actual origin. It's around the chimney, maybe the flashing. It only leaks in high wind.

Roofers are scarce around here lately.

You start with roof penetrations. Only after they're eliminated as sources of the leak do you rip up anything else. Otherwise, you're just playing whack-a-mole.

Not surprising. You might have to call someone back from Texas. ;-)

I had to find the leak, or the whole ceiling would come down. The stuff that I cut out was all wet and soggy, getting mouldy, so may as well go. I'll get a drywall guy in here to repair all that, after/if ever I stop the leak.

It doesn't rain here all summer, so the first good rain we get, everything leaks at once. All the roofers have to come back from their golf courses and country estates.

It's not worth making channels in the sheetrock. Pull it down in neat rectangles, spanning rafter to rafter. If it's that bad, the whole ceiling will have to come down anyway.

Or, from their new homes in Texas.

On a log scale, not much.

More like mixing cause and effect. It's much like observing an event makes one suspect that they caused the event. Also, coincidence does not imply causation: In this case, I find the correlation between Schumann resonances and earthquakes rather improbable. According to Google wisdom, Schumann resonances are caused by atmospheric lightning. Lightning bolts deliver quite a bit of energy, possibly sufficient to trigger an earthquake. The changes in Schumann resonance signals appear before the earthquake because of the differences in travel time through the atmosphere versus through the ground. At least, that's the way I read between the lines and techno babble. The problem is that lightning bolt usually start on the ground and radiate upwards. If there's any delivery of kinetic energy from the bolt, it's to the clouds. I also don't see lightning bolts producing gigantic craters that would be expected from a transfer of energy to the ground.

I should add "natural philosopher" to my resume.

I've been patching my 5 degree pitch (almost flat) roof for about 40 years. Every year, it leaks. Every year, I dump some more wet patch on the roof trying to find the elusive leaks. After 40 years of trial, error, and refusing to accept expert advice, I believe that I have successfully executed every possible mistake and have taken precautions to avoid their repetition.

This year, I made an important discovery. The edges of the roofing material are not very well sealed and might sucking water into the house between the roof, tar paper, and roll roofing. I found this by cleaning off the accumulated debris at the edge of the roof with a garden hose for the first time, and finding a large puddle of water inside the house. I was under the mistaken impression that water does not flow uphill, but apparently it will go uphill on a 5 degree slope.

Anyway, I'm accustomed to dealing with roofing tar, wet patch, and emulsified latex for patching the roof, and the various protective measures required to avoid transporting the inevitable mess from the roof to the inside of the house. I have my sacrificial worn tennis shoes, my jeans with the black goo spots, a shirt with tar on the cuffs, a jacket that tarred elbows, and a black hat that doesn't show the tar spots. I also wear neoprene gloves, knee pads, and safety glasses. All the aforementioned are now spotted, smeared, and encrusted with tar. When working at the edge of the roof, I place some plastic film on the deck below, so that should I drop some tar, I won't later step in it. Of course, I shed everything that might have tar on it before entering the house.

We'll know if it worked when it rains again in 2 days.

Nice mess and looks expensive to fix. Getting the paint to match might be tricky. My house has energy deficient open beam ceilings, where there is no attic to hide the leaks and no ceiling to act as a sponge. Despite these alleged benefits, it's still a PITA to find the source of the leak. Water will enter in one place, move sideways to the edge of the 3ft wide tar paper sheet, than then drip onto the most expensive furniture. The means the source of the leak on the roof is within a 3ft radius of where it's dripping.

Incidentally, I've tried making my own roof moisture detector using a cheap capacitance meter instead of buying one of these: It sorta worked, but only if the wood was thoroughly soaked. Your FLIR camera should also work at detecting wet areas.

A friend in the area had that problem with the part of the roof just uphill from his chimney. Despite 6" flashing, it was not properly buried in wet patch. The roofer used common roofing tar, which hardened over the years and cracked. When there are so many dissimilar materials together in one place, things are going to move around. The wind blew the water partly under the flashing and capillary action did the rest. I was amazed at the large amount of water that was transported into the house in this manner. Easily fixed by replacing all the flashing, and this time using wet patch, which remains somewhat flexible. You might also consider using white elastometric goo designed to remain flexible such as: When the weather improves, I'll probably dump a few gallons of the stuff on my roof to see if it works. My neighbor did half his flat roof with the stuff (he ran out of money) and claims that it solved his leaky skylight and chimney problems.

Yep. Storms do that. That's one reason I like to do my own roofing. (Another is that I'm cheap).

Good luck.

I got the wet parts out... had to chase the stream halfway across the room to find the source. I'll let a sheetrock guy clean it up.

My wife does *not* like the current look.

The next plan is to squirt food coloring here and there around the outside of the chimney, in the rain, to see where the water is getting in.

I saw one leak, it didn't take much rain to provoke it, but the roof looked perfect from above. New sheet roofs just don't leak.

So I go into the crawl pace above the ceiling and discover that the roof looks fine above the wet spot. but the wet spot is at a join in the steel channel that the plaster sheetinng is screwed to, so I back-trace and find an air-conditioning plant with a dodgy U-trap on the condensate tray outflow that would drip into the channel...

When it rained the relative humidity would go up and the plant would produce enough condensate that it wouldn't evaporate before reaching and soaking through the ceiling.

It's easier to take sheetrock down in sheets, or at least partial sheets. Less mess. The home improvement channels all do it the hard way (they never show how much work the cleanup is after their elephants come through).

BT. I had to chase a leak in a previous house. Ended up being the drain in the master tub. It was intermittent so never leaked when I was looking. Someone had to be standing in the right (wrong?) place in the tub for it to leak,

Toilet paper works well, too. If it's the chimney, don't screw around with it. Have the flashing ripped out and have it done right. Sealing goop doesn't work.