high frequency screen 4 killer

screening - astec

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5 best ultrasonic pest repellers - july 2021 - bestreviews

Emits ultrasonic and electromagnetic waves that repel rodents, roaches, flies, and bugs. Covers a large surface area. Chemical-free and safe for humans and pets. Built-in on/off button. Operates silently and is energy efficient.

Comes in a pack of 4. Features a mix of ultrasonic frequencies that drive pests away. LED light indicates when waves are working. Each repeller includes an extra AC outlet and safety cover. Free from odors and harmful toxins.

Effectively combines 3 different types of waves. Quick installation. Easily covers 1,100 square feet. Actively repels bugs, rodents, and bats. Affordable. Safe and silent for humans and pets. Noticeable difference over a week.

Works in green, blue, and red modes that are effective for minor, medium, and severe pest infestations. Green and blue modes are completely silent. Drives away all types of pests. Can be used in very large rooms.

Uses two types of silent waves to repel many kinds of pests. Comes with a light that indicates when its working. Consumes less power than other brands. Safe to use, and free from odors, harmful toxins, and chemicals.

If youre looking for a clean, nontoxic way to deter mice and bugs from squatting in your home, an ultrasonic pest repeller is an excellent alternative to expensive pest-control services or dangerous chemical traps. These devices are designed to repel pests capable of hearing ultrasonic frequencies, but not to worry. Human ears cant hear the sounds.

The BestReviews team wants to simplify your shopping experience by giving you all the information you need to make your final choice. Weve created this shopping guide with an overview of ultrasonic pest repellers to help you keep your house free of nasty cupboard critters.

These devices deter pests with ultra-high-frequency sound, frequencies higher than 20,000 hertz. Humans cant hear the sound emitted by these devices, but some animals and insects are fully capable of picking up ultrasonic sound waves. The high-pitched sound ranges from irritating to deadly, depending on the critter and the strength of the device in question. Ultrasonic devices are powered by electricity and available in plug-in or battery-operated models.

Its important to note that this type of device is not effective against all pests. Certain insects, like ants, are more resilient than others when it comes to ultrasonic frequencies. Some studies have also shown that ultrasonic repellers may even attract critters (such as mosquitos) into your dwelling. Correct positioning and use of these units is the best way to maximize effectiveness, but dont think of it as an instant solution to pest problems. It takes time for repellers of this type to produce a measurable effect.

Some repellers are designed to deter specific types of pests, such as insects or rodents. Others are designed to target all the nasty critters that might invade your property. Larger repellers are made to control deer and cat populations.

You can choose a pest repeller to use outdoors or indoors. Weatherproof and waterproof outdoor units are used to repel critters like squirrels and chipmunks. Avoid using a unit outdoors if your pest problem is mainly indoors. You might drive unwanted critters into your home!

Most common are plug-in units. These are small, unobtrusive, and easy to plug into any electrical outlet around your house. Corded options are bigger and usually provide more coverage, but youll need an accessible outlet nearby. If you dont have a conveniently located electrical outlet, a battery-operated pest repeller makes it easy to place a unit anywhere in your home.

Its important to be realistic. This type of device wont wholly eliminate unwanted pests from your home, and it cant repel every kind of critter. Its also not a long-term solution. Some pests could become accustomed to the high-frequency sound over time. If you have a severe pest problem, an ultrasonic device isnt a practical solution. High-frequency-emitting devices are best for controlling light pest issues and preventing bugs and rodents from taking up residence in your home in the first place.

For the most part, a larger repeller is stronger and provides more coverage. Correctly placing the repeller will maximize its performance. An incorrectly placed unit, regardless of size, wont work as well. The sound emitted by these devices doesnt travel through walls. If mice are devouring the contents of your pantry, the repeller wont be useful if you stick it in the basement. Youll probably need multiple repellers for maximum coverage. Ultrasonic pest repellers are often sold in packs of two, four, or six because theyre more effective if spread throughout the home.

Some units combine ultrasonic and electromagnetic frequencies for maximum effectiveness. Electromagnetic technology is capable of penetrating walls and other obstacles. The pulses emitted target the nervous system of nasty household pests.

The cost of an ultrasonic unit depends on the brand, coverage provided, and how many different pests it repels. Most repellers come in packs containing two, four, or six units and cost less than $40. The priciest options are designed for outdoor use, and most of these cost less than $60.

A. Choose an open area for best results. Furniture and walls can stop the transmission of high-frequency sound waves. If youre putting one in your living room, for example, avoid positioning it behind the couch.

A. Since theyre typically designed for use indoors, you shouldnt be too worried about harming the good bugs outside your home. The ultra-high-frequency sound waves cant travel through walls. Many beneficial insects are sensitive to ultra-high-frequency sounds, so using an outdoor unit could harm the good bugs around your yard. We dont recommend using an ultrasonic device outdoors for this reason.

A. Humans cant hear ultrasonic sounds, but some pets might be sensitive to certain frequencies. Dogs and cats should be fine around these devices, but smaller mammals like pet hamsters and mice shouldnt be housed near an ultrasonic pest repeller. Birds might also be susceptible to high-frequency noises. Carefully read manufacturer guidelines to make sure your furry and feathered friends stay safe.

A. It can take as little as a week or as long as a month. The length of time it takes to reduce the pest population in your home depends on the level of infestation and the strength of the device(s) used.

solids control, solid liquid separation technology | h-screening

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Verti G Cuttings Dryer and Decanter Centrifuges are thesolution that can dramatically reduce waste volume and reclaim much drilling fluids back to the active mud system, and meet increasingly strict environmental regulations. The oil on cuttings (OOC) of the cuttings dryer is less than 5%. In order to total dispose of the solid cuttings, thermal desorptiontreatment are introduced, after treatment the cutting oil contentis<0.3%which is ready for landfill. Mud oil are recovered for remixing oil based drilling mud.

Solids control system is the most import part of oilfield mud circulation system. The efficient solid-liquid separationprocess accomplish by linear motion shale shaker, desander/desilter hydrocyclones, (mud cleaner) and decanter centrifugeis the so called 4 phase solids control. According to the drilling condition and mud volume requirement, a number of solids control equipment and mud tanks are combined to work as a whole for continuous mud flow circulation. The mud system is customizable upon request.

Mud recycling system for HDD (Trenchless) or TBM applications adopts the solids control concept from oilfield, but requires the most compact structure as possible. The mini mud system is often a highly self-contained tank skid with shaker, hydrocyclone unit and centrifugal pumps. Mud hopper is configured if to mix the fresh drilling mud.There is often a mud pit at the field site, dirty mud is transferred by a slurry pump andsentinto mud recycling unit for cleaning. The cleaned mud will comeback to the drilling rig for reuse.

high frequency carrier screen (11 genes) - sema4

The high frequency pan-ethnic panel provides carrier screening for the following genetic disorders due to the relatively elevated carrier frequencies and high detection rates in most ethnic groups with severe, early onset clinical presentation: Alpha-thalassemia, beta-thalassemia, beta-globin-related hemoglobinopathies: HbC variant, sickle cell disease, congenital disorder of glycosylation: type Ia, cystic fibrosis, Duchenne muscular dystrophy/Becker muscular dystrophy, fragile x syndrome, medium chain acyl-CoA dehydrogenase deficiency, phenylalanine hydroxylase deficiency, Smith-Lemli-Opitz syndrome, and spinal muscular atrophy.

Although this testing can detect the majority of disease-causing pathogenic variants, a negative result does not eliminate the possibility that an individual is a carrier of a rare pathogenic variant that was not identified. Please refer to the residual risk table to determine the risk following a negative result.

5 best ultrasonic pest repeller reviews for powerful pest repelling

An ultrasonic pest repeller uses the latest ultrasonic technology to drive away pests, and as this innovative device is an environmentally friendly way of keeping your home pest-free, it is an excellent cost-effective choice for residential pest control.

When it comes to controlling insects and rodents that want to share your living spaces, there are lots of pest control products available for residential purposes. You can buy sprays, glue traps, bait stations, or powders, but if you prefer a non-toxic, chemical-free form of pest control that is quick and easy to use and with no mess to clean-up, then there is a better solution.

Our top pick for the best ultrasonic pest repeller is the TBI Pro Ultrasonic Pest Repeller. We highly recommend the TBI Pro 2-pack as a total pest eradication solution against nasty crawling and flying pests.

There is nothing worse than cooking, watching television, or settling down to sleep when spiders, cockroaches, flies, or mice take over your home. However, when you install the TBI Pro, it will unleash its dual powerful electromagnetic and ultrasonic waves and banish any pests so that you can live in peace.

Once the device starts broadcasting its high-frequency stay-away message around your home, within just a few weeks any creepy crawlies or small rodents will run away from your home to a quieter and safer feeding breeding ground.

This very innovative dual approach to pest control is ideal for covering an extra-large area and can get rid of insects and rodents that may seem to have developed a resistance to the ultrasonic sound waves.

As we live in an age of constantly evolving technology, where new products are allowing us to take more control over pest problems, there is always the possibility that not everyone will experience the same level of success with a product.

However, in saying this, most pest repellers do live up to their claims. It needs to be said though, as good as the device is, to be able to see the results you want, the device has to be used in accordance with the manufacturers instructions.

Also, you need to remember that pest repellers are not designed to kill the pests, though the device may have this effect, it is designed to repel them by targeting the insects or rodents nervous system and causing them such stress that they would rather be anywhere else but in your home.

Once you set up one or more UPR devices it can take up to a month to see any significant results. If you have a larger infestation, you can always use a combination of traditional pest elimination products together with the ultrasonic pest repeller.

If you are using a UPR in just one or two rooms, the pests may move from room to room to escape the high-frequency sounds that only the pests can hear, but they will soon leave your residence to a place that is more peaceful.

Some manufacturers of UPRs produce electronic devices that are designed to repel certain types of pests. Depending on the manufacturer and model, and the type of frequency sounds that are broadcast, devices may repel all types of insects and small rodents like rats and mice and may even drive away squirrels, while other models may only be effective at targeting insects.

The effectiveness of the device is also based on the proximity to which it is placed near the offending pest or pests. While a device may be effective in driving away mice from the top floor of a house, depending on its range, it may not discourage them from setting up home in the basement. To get the best effect, especially if you have a large house, you may have to set up 4 or6 UPRs for an overall effective pest control strategy.

For those of us who have pets, the question of whether a UPR can safely beused where our pets live is critical. One of the reasons that a UPR is a great choice for people who have pets is that you can use the device without having to worry about nasty chemicals, traps, or odors that can harm your feathered or furry friend.

However, what about the high-frequency sounds? The ultrasonic sounds that UPRs send out fall outside the hearing ranges of humans, cats, dogs, and birds, so while they are distressing for pests, they are not distressing for pets. However, household pets such as hamsters and rabbits could become distressed around some of these devices.

Also, if you choose to use a devicethat is designed to cover a large area of up to 5,000-square-feet and emits an exceptionally high-powered level of ultrasonic sound waves, it may not be the best choice if you have dogs, as they can become distressed around the device.

Some UPRs can cost less than $20.00, while other models cost around $40-$50. The price is determined by a few factors, the size of the device, whether the manufacturer is selling one device or a 4 or 6-pack, and the coverage that the unit can provide.

The coverage area of a UPR relates to the area that the sound waves can cover. A small, single-unit may cover a small room up to 80-square-feet. Some units are designed to cover a medium to a large area of1200-1290-square-feet, while a more powerful unit may cover an extra-large area up to 5,000-square-feet.

The effectiveness of an ultrasonic repeller will depend on the size of the room where you will be using it. So if you are planning to get rid of mice, rats, or squirrels in your attic, a repeller that is designed to cover a medium or large room would be ideal.

How many of us have pulled our new device out of the packaging, set it up, and wondered why it is not functioning as the manufacturers product description told us it would function? I have been guilty of this many times.

To avoid any frustration, read the UPRs instructions such as installing the device at the required distance from the floor, or avoid placing the unit at the back of curtains, behind fridges, or any other furniture that may interrupt the frequency.

Although the sound waves that UPRs emit are very powerful, they cannot travel through walls, so if you want an overall pest prevention system for your home, choose a 4-pack or 6-pack and place the units in different rooms.

An economical home-friendly pest repelling solution, this 6-pack contains all the devices you need to control pests within your home. Each unit has an effective coverage area of 800-1200-square-feet so it is ideal for a kitchen, living room, bedroom, bathroom, basement, attic, crawl space, garage, barn, or shed.

Wherever you have spotted crawling or flying pests, plug in a unit 7-16-inches away from the floor and make sure that it is installed vertically to the floor. Depending on the level of infestation, the Bocianelli will stop insects and rodents from invading your personal space within 3-4 weeks.

100% safe for humans and pets, the pest repeller uses no chemicals or poisons, produces no radiation, and is noiseless. It is equipped with powerful advanced ultrasonic technology that effectively drives pests away like ants, spiders, mice, mosquitoes, roaches, and ants without killing them.

This smart pest repeller features an innovative design that makes it very effective at driving away a wide range of pests from your home such as fleas, spiders, cockroaches, ants, mosquitoes, mice, and rats within 3-4 weeks.

As the unit has a high sound pressure ultrasonic speaker, its powerful frequencies can even pass through walls, floors, and ceilings, which makes this repeller perfect for an 800-1200-square-feet room. You can even use both units together for a larger space up to 4000-square-feet area, like a double-story house.

Take full control of your pest extermination needs by utilizing the 2 settings. For everyday pest eradication needs, use the super electromagnetic ultrasonic frequency. If your home is under a full-scale invasion, use both frequencies together as a combined force against pests and ensure that they do not become immune to the ultrasonic sound.

Its advanced ultrasonic technology effectively drives away pesky pests like mice, ants, mosquitos, cockroaches, spiders, and vermin away from your home in just 3-4 weeks depending on the intensity of infestation.

A human and pet-friendly way of repelling pests, the Defender Pro is environmentally safe, chemical-free, and radiation-free. It releases a silent 65 KHz frequency that actively drives away pests from your living space instead of killing them.

Designed with innovative ultrasonic technology, the Ever Pest repeller has an advanced design that produces a more powerful frequency that effectively chases away nasty pest invaders without killing them. In-just 3-4 weeks, you and your family will enjoy a pest-free environment.

100% safe for your family and pets, the Ever Pest repeller uses no chemicals, poisons, and you do not have to clean up dead pests. The electronic device emits a 65 kHz high frequency that irritates mice, mosquitoes, flies, rats, roaches, crickets, and other rodents, but is inaudible to humans.

The power-packed pest eradicator uses the latest in ultrasonic wave technology to efficiently drive pests from your home without killing them. It is ideal for any 800-1200-square-feet area so you can place the device in the kitchen, bedroom, lounge-room, or office.

Whatever type of pest likes to invade your home, the Neatmaster offers you complete control over just about any type of pest on the planet such as mice, rats, cockroaches, spiders, mosquitoes, millipedes, ants, termites, bedbugs, silverfish, wasps, fleas, ticks, and cicadas. You choose from 3 settings to perfectly suit any level of infestation.

The green light setting is for slight pest eradication needs. For everyday pest needs, select the blue light setting for a more powerful burst of the ultrasonic frequency. If your home is under a full-scale invasion, the red light setting switches on a super-powerful burst of ultrasonic waves.

For efficient performance, the Neatmaster should be installed at least 2-4-feet away from the floor and should be vertical to the floor and plugged into the outlet. In just 3-4 days pests will stop invading your home and look for another place to set-up camp.

Our top pick for the best ultrasonic pest repeller is the TBI Pro Ultrasonic Pest Repeller. We highly recommend the TBI Pro 2-pack as a total pest eradication solution against nasty crawling and flying pests.

There is nothing worse than cooking, watching television, or settling down to sleep when spiders, cockroaches, flies, or mice take over your home. However, when you install the TBI Pro, it will unleash its dual powerful electromagnetic and ultrasonic waves and banish any pests so that you can live in peace.

best 4k gaming monitors for pc 2021: 144hz, curved and more | tom's hardware

With great pixels comes great image quality. Soit's not surprising when PC gamers drool over monitors with 4K resolution. A panel packing 8.3 million pixels (3840 x 2160) makes your favorite games look incredibly sharp and realistic. In addition to being the highest resolution you can get in a good gaming monitor these days, going 4K also offers the ability to expand past 20-inch screens. With that loaded pixel army, you can stretch your screen size well past 30 inches without having pixels so big that you can see them.And the new graphics cards from Nvidia's RTX 30-series and AMD's Radeon RX 6000-series make the move to 4K even more tempting.

But that image quality comes at a steep price. Anyone who's shopped for a 4K monitor before knows they're not cheap. Yes, 4K is about high-res gaming, but you're still going to wantsolid gaming specs, like a 60Hz-plus refresh rate, low response time and your choice of Adaptive-Sync (Nvidia G-Sync or AMD FreeSync, depending on your system's graphics card). And you can't forget the cost of the decently beefy graphics card you'll require to game properly in 4K.If you're not ready for 4K yet, see our Best Gaming Monitors page for lower-res recommendations.

With speed, accurate color and high contrast, the LG 27GN950-B is the best 4K gaming monitor and our top recommendation. Theres tough competition on this page, but the 27GN950-B stands out with some of the best input lag scores weve seen of a 144Hz monitor (tying with the Asus ROG Strix XG27UQ below) while also keeping up with its rivals in our response time testing.

Image quality is also a sight to hold. With an edge array backlight with a local dimming feature, the 27GN950-B doesnt quite hit FALD-level HDR but still brought stellar performance with 8,475.3:1 contrast ratio. LG also implemented its Nano IPS panel, the answer to Samsungs Quantum Dot tech, to achieve massive color coverage (94.5% of DCI-P3 and 133.9% of sRGB after our recommended calibration) that really made games pop.

The Asus ROG Strix XG27UQ is the best 144Hz 4K gaming monitor and may be cheaper than you expect. We've seen it listed for $800, but as of writing it's going for $1,000. The XG27UQ doesnt have a premium FALD backlight for beautiful HDR; however, HDR performance is still impressive, thanks to an effective edge-array backlight and the screen's Dynamic Dimming feature.

The ROG Strix XG27UQ stacked up well in our testing when it came to both response time and input lag. In the input lag test, it outperformed other 144Hz monitors, including the Acer Predator X27 and Asus ROG Swift PG27UQ, which went for about $2,000 each. And while the XG27UQ is listed as a FreeSync monitor, we were able to run G-Sync on it successfully.

A little more affordable than the other 144Hz options on this page, the Acer Predator XB273K is the best 4K gaming monitor at that ideal refresh rate for value-seekers. During fast-paced games with settings maxed, there was no blur. G-Sync worked successfully--with both standard and HDR content-- to fight screen tearing when paired with an Nvidia graphics card. The monitor kept up well with other 144Hz displays during our testing and even beat the Asus ROG Swift PG27UQ and Acer Predator X27, which are about $2,000 monitors, when it came to input lag.

In terms of image quality, the Predator XB273K delivers with pro-level color accuracy and contrast that reached over 4,000:1, according to our testing, and over 2,000:1 after our calibration. HDR doesn't look as good as it does on monitors with FALD backlights, but we consider the Predator XB273K the next best thing.

If you want the best 4K gaming monitor for HDR movies and games, the Asus ROG Swift PG32UQX is an expensive, but impressive, buy. This is the first gaming-focused monitor with Mini LED. Thanks to that advanced backlight, we recorded an amazing HDR contrast ratio of 180,820.8:1. And while an OLED screen like the Alienware on this page can offer deeper, purer blacks, the PG32UQX can get much brighter. It hit 1,627 nits with HDR during testing.

We loved watching HDR films on the screen, but theres no Dolby Vision support. This wont affect many games, but 4K Blu-ray discs and content from Netflix and the like often use Dolby Vision. On the other hand, you do get support for 24p film candences.

And as a gaming monitor the PG32UQX is no slouch either. It performed admirably against other 144 Hz screens in our response time and input lag tests, even besting some, including the HP Omen on this page, in the latter. And the nifty OLED screen on the bottom uniquely relays helpful information, like refresh rate adn CPU and GPU temperatures.

You dont often see the word budget associated with a 4K monitor, but the Asus TUF Gaming VG289Q isnt just affordable, its a great gaming monitor too. Despite being available for $349 as of writing, it offers a great amount of performance, making it a fantastic value for gamers looking to get to 4K without breaking the bank.We've even seen 4K monitors at the $400 mark offer lesser gaming performance.

There was no ghosting when we gamed on the VG289Q, and overdrive successfully helped eliminate motion blur. SDR titles looked extra colorful, but there was hardly any improvement when moving over to HDR games.

With the VG289Q priced so low, its not surprising that its refresh rate is limited to just 60 Hz (FreeSync works down to 48 Hz). Hardcore gamers will want more Hz, but casual players can make due with fast-paced scenes showing sufficient detail and great pixel density.

The lines separating the monitor needs of gamers and professionals keeps blurring. Besides that, theres nothing wrong with a photo editor wanting to game during their free time, right? The Acer ConceptD CP271K is the best 4K gaming monitor for professionals because it boasts impressive gaming specs coupled with accurate color space coverage.

Creative professionals can get work done with the monitors 110% coverage of the DCI-P3 color space, although the very meticulous will find that to be slightly too colorful. You can, however, reduce color with a software look-up table. You also get great HDR output with a FALD backlight that reaches 1,000 nits.

At the same time, the ConceptD CP271K offers gamers accurate sRGB coverage (96.3%), as well as powerful performance that kept up with 144 Hz gaming monitors in our response time and input lag benchmarking.

If youre looking for a big 4K experience, the Aorus FV43U offers excellent image quality and gaming performance at a much cheaper price than screens with slightly lesser image quality. We've seen it for as cheap as $1,000, giving the $1,500 Asus ROG PG43UQ on this page a run for its money by besting it in our contrast (both SDR and HDR) and max brightness tests, as well as color coverage. The Asus beat the Aorus in our response time test by 1ms and in input lag by 7ms, but unless youre an extremely competitive gamer, thats probably worth the price savings and slight image quality advantages.

The Aorus FV43U also offers USB-C connectivity, allowing you to hit 144Hz, two 12W speakers that sound better than most and a remote. HDR performance is also top-of-the-line, with our benchmarks recording 38,888.4:1 contrast and HDR games showing amazing depth and popping textures. A lack of 24p and Dolby Vision support hurt the FV43Us chances as a full TV replacement, but there isnt much else missing in a premium gaming monitor here.

We loved the Asus ROG Swift PG43UQ when we first saw it in June, but its been hard to find online ever since. We reviewed it at $1,500 but have seen it sell for more. If you can find this massive screen at the right price, you wont be disappointed.

At 43 inches, the ROG Swift PG43UQ is juggernaut that makes for a great TV replacement -- it even has a remote. From a 4-foot distance, it lends to a highly immersive experience that rivals a curved ultra-wide. And with DisplayHDR 1000 certification, HDR movies pack a punch. Games looked incredibly realistic and warm in HDR and also natural and vibrant in SDR.

Most importantly, the PG43UQ is specced for high-performance gaming. Response time competed well against other 144 Hz screens in our benchmarks, and input lag was better than the equally priced Acer Predator CG437K.If you can't find the Asus in stock though, the Acer's a fine substitution with a drop less performance for around $1,500.

The Samsung UR59C isnt a gaming monitor exactly, but youd be surprised at the speed it offers compared to other curved 4K so-called gaming monitors. For example, the MSI Optix MAG321CURV, a 32-inch curved 4K gaming monitor, showed a 22ms response time in our testing and 71ms input lag, while the UR59C posted the same response time but a shorter 63ms input lag. Make no mistake, this is not a high-end gaming monitor. But 4K at 60 frames per second (fps) is a lot more attainable than 144 fps, which may make the lack of Adaptive-Sync acceptable, depending on your GPUs capability. And the low price makes this one of the best budget 4K monitors overall too.

We havent seen very many curved 4K gaming monitors but found the UR59Cs 15000mm curve noticeable and effective in upping productivity with multiple windows open. The curve didnt feel as extreme as it would on an ultrawide, but that also meant no distortion.

Games looked tear free and without obvious lag when we paired it with a GTX 1080 Ti, while the VA panels high contrast 2,648.4:1 out of the box, according to our testing) made cut scenes feel like a movie and graphics, like trees and dirt, more realistic.

With a massive 55-inch panel and OLED technology that provides the deepest blacks around and amazing contrast, the Alienware AW5520QF is the best 120Hz 4K gaming monitor, offering a more manageable refresh rate for your GPU than the 144Hz options here, while also being the best 4K gaming monitor you can nab for HDR.

This screen is a great fit for the living room. The first real OLED gaming monitor, it delivered the best image quality we had ever seen at the time, including immeasurable blacks and, therefore, theoretically unlimited HDR and SDR contrast.

But the Alienware OLED still isnt perfect. Max brightness with regular SDR content is just 130 nits, while HDR only bumps it up to 400 nits. That means its potential is best realized in a darker room. But keep in mind that with its large size, 150 nits with SDR would've been acceptable, so the monitor is only a little bit short. But the AW5520QF's also expensive--even by OLED TV standards. And for better audio, consider the HP Omen X 65 Emperium below.

If you're looking for the best 4K gaming monitor for the PS5 and Xbox Series X, opt for something with HDMI 2.1, like the Gigabyte Aorus FV43U. With the AW5520QF's HDMI 2.0 port, you'll be limited to 60Hz.

If youre a couch gamer, you need a monitor thats fit for replacing your TV. With a 64.5-inch display, the HP Omen X 65 Emerpium is amply equipped to do just that. This juggernaut of a gaming monitor offers larger-than-life gaming. In testing, performance matched its high price tag with zero gaming hiccups and high frame rates at high settings.

HP also included some unique bonuses that make this monitor even more fitting for the living room. An included soundbar featuring four 4-inch woofers, two 1-inch tweeters and two passive radiators add to the feeling of immersion. The monitor also comes with Nvidia Shield Android-based streaming interface, which means gaming, TV and movie-streaming options are built right into your gaming display. A remote completes the living room package.

Whether you're shopping for one of the screens that made our list of best 4K gaming monitors above or something else, you may find savings by checking out our best monitor deals page, along with our lists of Dell coupon codes, Lenovo coupon codes, LG coupon codes, HP coupon codes, Monoprice coupon codes and Newegg promo codes.

Scharon Harding is a Senior Editor at Tom's Hardware. She has a special affinity for gaming peripherals (especially monitors), laptops and virtual reality. Previously, Scharon covered business technology, including hardware, software, cyber security, cloud and other IT happenings, at Channelnomics, with bylines at CRN UK.

high frequency apparatus and experiments | tesla universe

Many experimenters either do not realize the vastness of the high frequency field, or think that they have not money enough to buy the necessary apparatus. It is the purpose of this article to explain the manner of constructing a few simple instruments, and the method of carrying out some simple experiments.

In the first place, a high frequency transformer must be constructed. An Oudin coil will be the best for all-around work, and it may be made in the following simple manner: Procure an ordinary pasteboard mailing tube, about 2 inches in diameter and 10 inches long, and cover it with a thin coat of white shellac. While this is still wet, wind the tube with fine copper wire, spacing the turns far enough apart to ensure proper insulation. (Enough wire may be found in an old telephone ringing magnet.) Glue this tube upright to a base and fasten three posts on the base. The primary coil may be made of 6 turns of No. 14 copper wire, connected as in the diagram, Fig. 1.

A condenser can be made by coating both sides of old photographic plates with tin-foil, and placing them in a cigar box, to hold them in an upright position. A spark gap of most any type will answer. A 1 inch spark coil should be used.

When the above instruments are constructed, they should be connected up as shown in diagram, and the apparatus is ready. When the spark coil is operated, a brush discharge of purple light should appear around the free end of the secondary, upper end of coil, with sparks about 2 or 3 inches in length. If a piece of metal is held in the hand, a very long spark can be drawn from the secondary wire, without the slightest shock. If, however, the spark is drawn directly into the hand, a severe sting may result. On the other hand, if a pane of glass is held between the secondary wire and the hand, a spark may be received directly into the hand without pain; the spark, being dispersed or spread out while passing over the glass.

If a person insulated from the ground grasps the free terminal of the secondary, a match may be lighted from any part of the body. A Geissler tube will light up brightly, when brought near the body. This is also a good way in which to treat heart and nervous diseases. If there is any local trouble, a grounded metallic object should be brought near the point to be treated, thus taking out the induced current at this point.

An interesting experiment is to produce an artificial Aurora Borealis. This may be accomplished with a large electric bulb (a 100 watt, burned out one will do), covering the tip with tin-foil. Insulate the bulb from the ground and fasten the screw end to the secondary wire. Place a strong permanent magnet on each side and start the coil. A beautiful auroral effect will form inside the bulb. Also, if there are any loose pieces of filament, these will begin to revolve rapidly about the inside of the bulb and will continue to do so for some time after the current is shut off, and each time they touch the glass a shower of sparks will fly in all directions.

A by-product of high tension electrical stress in the air is ozone. Ozone is merely electrified oxygen. When a high voltage discharge takes place in air or pure oxygen gas, the atoms of oxygen are torn apart and exist in what is known as a nascent state. In this state each atom combines with one other atom, and the chemical affinity of these two atoms is such that, as there is nothing with which they can combine, these atoms pull to themselves and combine with a third atom of oxygen. Thus it is that a new gas is formed. This gas is much denser than oxygen and is many times as active. The smell of ozone is very strong and there seems to be a slight difference in the smell of ozone produced with a static machine and the ozone produced with high frequency current. Ozone is an excellent germ killer, as it kills all kinds of disease germs on contact. If it is administered properly, and in time, it will cure consumption.

The electric stress about the coil is so great, that immense quantities of ozone are constantly being generated. In order to treat diseases obtain a box which is large enough to contain the coil and still leave enough space (about 4 inches) on each side to prevent the coil from grounding. Run the coil wires through the box and leave the free end of the secondary about six inches long, so as to obtain good radiation surface. Place a hose in the top of the box and another in the lower part of one side. Paraffin the box to prevent leakage, and put a small window in one side so that the coil action may be viewed. Either air or pure oxygen is taken in thru the lower hose and the ozone is inhaled, or otherwise applied from the upper hose. In fumigation, treatment of coughs, pneumonia, colds, and for many other medical uses, besides oxidation of certain materials, bleaching flour and cloth, experimenting with its use in welding and many other commercial uses, ozone is a most valuable agent.

Taking the high frequency field as a whole, it is well worth while for more experimenters to work with it. High frequency current has the properties of both static and galvanic electricity, besides many properties which neither of the above possess. It will pass over ordinary insulators, such as glass, almost as easily as low frequency current will pass thru copper. It travels over the surface of a conductor and seldom thru it. Its oscillations are so rapid that it will not produce an audible sound in the receivers, so that the discharge of an Oudin coil cannot be used for the transmission of wireless messages, altho who can say, if it is properly conducted to the aerial, that it does not travel as far or farther, than an undamped wave.

busted: 5 things you dont know about deer senses | deer hunting | realtree camo

The 10-pointer, thick as beef and rack glinting in the late-day sun, stepped out of the greenbrier, took a quick look around, lowered his head and began sneaking my way. I put tension on the bowstring. In less than 45 seconds the bucks route would take him through a shallow funnel less than 20 steps from my perch.

Twenty seconds later he stopped, snapped his head up, and wheeled back into the thicket with astonishing speed and agility. I hadnt moved. Hadnt made a sound. And the evening breeze was perfect. But the buck was gone, and once again I was left to wonder went wrong, and to marvel at the uncanny senses of a mature whitetail buck.

If Ive learned one thing in 30 years of whitetail hunting across North America, its this: If you want to shoot big deer consistently, especially with a bow, you need to learn all you can about how a buck sees, hears and smells, and then you need to devise ways to try and negate those awesome senses. Read on.

Dr. Karl Miller and cohorts at the University of Georgia have studied the whitetails vision intensively. The researchers have looked into the eyes of does and bucks with optical instruments, and even fitted deer with contact lenses. Theyve found four interesting things:

So lets say youre still-hunting and a grown doe sees you coming. Rather than bolting right away, she stares at you and starts the head-ducking and bobbing. You freeze. When she stops and appears to have calmed down, keep still! She will try to fake you out a few timeshead bobbing and stoppingbobbing and stopping. She might even look off to the side or away from you, only to snap back around and catch you moving. Old does, especially, are crafty. An efficient predator is wise to that.

Biologists say the whitetail possesses a peripheral vision range somewhere between 250 to 270 degrees, which helps a buck scan the woods and pick up predator movement at or just below the horizon. Deer are less adept at picking up movement above the horizon, so you can supposedly get away with more movement in a tree stand than on the ground. But you cant be careless.

I can tell you from experience that when a deer is 100 yards out and coming straight to your stand, youd better sit still. Remember both that wide field of view and their ability to pick up the slightest flicker of movement. Shift and move only when the deers head and eyes go behind cover.

University of Georgia scientists put does and bucks in sound chambers and monitored their brainwaves to see how the animals responded to different sounds and frequencies. They found that deer do not hear much better than we do.

The frequency of sound is measured in hertz. Studies have found that a healthy human can hear from 20 to 20,000 hertz, with our best and most sensitive range from 2,000 to 5,000 hertz. The researchers found that deer hear best at moderate frequencies of 3,000 to 8,000 hertz. To put perspective on it, both our normal speech and most deer vocalizations fall within these frequency ranges. So while deer generally vocalize at lower frequencies than we talk, they hear similarly.

How deer use their ears makes us think that they can hear a lot better than we can. Deer ears are like tiny satellite dishes that tip back and forth and roll around to pick up, sort out and lock onto various sounds in the woods. Think about this, because youve probably been there.

A buck is within 100 yards and hears you bang your bow or gun, or scrape your boots on a metal platform; you watch him work his ears, look your way and start stamping his foot. Wow, those ears are amazing and almost supernatural, you think. But that the animal is simply reacting to a strange and potentially dangerous sound in his environment, in much the same way that we jump and look if we hear a sudden horn or a car backfire nearby.

If you hike into a spot clanging a chain or clinking a strap buckle against a treestand, you might as well blare some Van Halen. Those heavy-metal sounds will either spook deer outright, or at least cause them to roll their ears, go on red alert and stare your way. A bucks ears are not that hard to beat. Just use common sense and be as quiet as you can.

This is an easy one to battle: Wear the best camo going. With 12 warm, natural colors and a proprietary printing process, Realtree Xtra allows you to blend in and avoid those pesky prying eyes. If you're looking for added concealment that's fast and easy to deploy, check out the UnderArmour Speed Freak blind made by Ameristep. It features UA scent control, leafy edges and super-fast setup.

For silence, you'll want to employ quiet camo. And Bass Pro Shops' Redhead line offers an array of soft, quiet fleece outerwear that will do the job without breaking your budget especially right now. Bass Pro has a ton of its Tech series on clearance and you get free shipping.

If you're just not the type to stay quiet, you'll want to make deer noises. And this is best done with a good deer call. There are few deer sounds louder than those of rattling antlers. Natural shed antlers are great, but bulky. To save space and still raise an authentic ruckus, check out Da' Bonehead Rattle Call from Knight and Hale. It looks cool, sounds great and takes up little room in your pack.

If you want to add some aromatic charm to your hunts, Code Blue has the pee for you. From bucks to estrous does, Code Blue has a full line of stinky potions that just might work olfactory wonders for you this fall.

Researchers at Mississippi State University found that a deers sense of smell, like a dogs, can be anywhere from 500 to 1,000 times more acute than a humans. Furthermore, scientists say that whitetails have thousands of sensitive receptors in their nostrils, which they use to sort out up to six smells at one time.

For more than 50 years Leonard Lee Rue III has observed, researched, photographed and written about deer. He has done more to educate the American public and hunters on the ways of the whitetail than anyone.

You ought to spend as much time as possible on your hunting property year-round, working on the habitat, scouting and hunting. Every day youre out there, monitor the wind directions at morning, midday and afternoon. Mark the currents on a map or in a journal. Over time youll see the common winds that accompany various weather patterns at different times of the year. That is vitally important info because the majority of the trees you pick for stands will be based on the prevailing winds in your area.

Most hunters focus on where deer will come in on the upwind side of stands. That is surely important, but it is not enough. When picking a tree, you need to determine where to put your wind, and hence your scent, so youll alert as few deer as possible. If a mature buck circles in somewhere downwind of your stand and smells you, he might just melt away into the brush. But an ornery old doe might stand out there and blow like crazy, alerting every deer within a half-mile that she smells a rat. Either way your hunt is probably ruined.

Always try to set up and float your wind over an area thats not going to see a lot of deer traffic. For example, let your wind scent drift away from your stand and out into a pasture field, or maybe out over a deep creek that deer probably arent going to cross. I sometimes set a stand slightly upwind of a steep hill or bluff that deer wont or cant walk up on the downwind side.

Determining the best wind for a stand definitely involves trial and error. You might look at a map or aerial and say, Okay, a southeast wind will work best there. But until you go in and sit the stand several times, you dont really know if a southeast is best or even adequate. You have to study the unique topography of an area because ridges, bluffs, draws and other terrain features can dramatically affect wind direction. You also need to observe the overall deer movement throughout an area as it relates to various common winds.

Most hunters concentrate on wind direction, but they often neglect wind speed. Big mistake. I have treestands on the tops of ridges that are perfect for high-pressure mornings with little wind. I also have sets in draws and hollows that are just right for strong northwest winds that kick up after a front blows through. Ive got a great stand on the edge of a small food plot down in a bottom where, if the wind is above 5 mph or so and stays that way throughout the afternoon, Im OK. But if I try to hunt that stand on a dead-calm evening when the wind drops to nil at dusk, the cool thermals start shifting and falling, spreading my scent all over the bottom and messing me up big time. Youve got to keep all that in mind to beat a bucks super sniffer.

In a lab at Mississippi State University (MSU), researchers were working on ways to best collect and analyze volatile organic compounds (VOCs) from human body odor. Their goal was to use VOC detection to diagnose and monitor human diseases like diabetes. But their research led to a unique collaboration with the MSU wildlife department, which was studying and testing odor-reducing products for deer hunters.

Human scent is a complex mixture of hundreds of compounds given off by bacteria that live in our bodies and on our skin. Scent compounds also come from the human body itself when it breaks down molecules to make energy. The odors are emitted through the skin and breath. These substances the VOCs evaporate into the air and can spook deer when youre hunting.

Figuring out which specific ingredients of body odor spook deer is a challenge, the MSU researchers said. Each of us emits a unique scent, and that scent varies depending on what and when we eat, drink, exercise and sweat. To get a cross-section of scents, the researchers collected body odor samples from 65 people who for hours wore either an untreated T-shirt or a T-shirt treated with a spray designed to eliminate or mask a hunter's body odor.

The researchers tested four scent-eliminating sprays out of dozens on the market, though they did not identify specific brands. Based on analysis of the hundreds of VOCs emitted by the 65 people, researchers found that the sprays worked by greatly reducing the levels of 29 key compounds, either by killing bacteria, binding to the chemicals, or converting them into less volatile compounds.

how the hidden sounds of horror movie soundtracks freak you out - atlas obscura

Youre sitting in the movie theater; its pitch black except for the dim glow on-screen. Nothing scary has happened yetbut you see a person walking, alone. You feel an overwhelming sense of dread. A slow, growing hum murrs over footsteps, and you know the person isnt safe. You, perhaps, feel you arent safe watching.

You wait for the inevitable conclusion, fixed on what you might see, listening for the cue that a killer or monster is ready to attackthough nothing on screen hints at this. The source for your anxiety is elusive, but it was carefully crafted through hidden audible elements that play on human emotions, causing your hairs to stand on end. This is the brilliance of what music does in a horror film.

The way composers make the most out of their musical tools to induce fear is both an art form and a science. Since horror movies rely on music, movie score composers carefully consider how to use familiar sounds in unusual ways; this distortion of reality unsettles us even if what were hearing is, in many ways, obscured.

The sound itself could be created by an instrument that one would normally be able to identify, but is either processed, or performed in such a way as to hide the actual instrument, says Harry Manfredini, whose music score for Friday the 13th was cemented in the thrasher film genre of the 1980s.

The sounds that do this to us arent always unusual; but their deep rumblings or high-pitched squeals signal danger almost (if not actually) instinctively. Distressed animal calls, women screaming and other nonlinear sounds, which are irregular noises with large wavelengths often found in nature, were used in The Shining and other movies to create an instinctual fear response, as recorded in the test subjects of a 2011 study at the University of California. Often these sounds are buried in the complex movie score or, sometimes, as subtle sound waves that give an adrenaline rush like a mini, internal roller coaster.

Taking a sound out of one normal context and then placing it into a new, scarier one can do this. While some of these sounds are subtle, othersstick out so much they become characters themselves. People who have seen Friday the 13th learned that a specific sound (a human vocal noise described as ki ki ki ma ma ma by Manfredini) means that the killer, Jason Voorhees, is lurking nearby with his machete, even if he isnt shown on screen. Just knowing that Jason might be in the room with us heightens our senses, and even though the sound is vocal, its unlike one any that a person would normally make. When Jasons sound is isolated, you hear breathiness in an echo; but the surrounding music and bloody visuals work together, bringing the noise to a functionally creepy place.

One unsettling and hidden sound that is given credit for freaking out an audience is infrasounda low-frequency sound that cannot be heard, but literally unsettles human beings down to our bones. Infrasound, which exists at 19 Hz and below, can be felt, but human ears begin to hear sound at 20 Hz. Infrasound exists in nature, and is created by wind, earthquakes, avalanches, and used by elephants to communicate over long distances. At a high enough volume, it may be possible for humans to perceive sound as low as 12 Hz, but even common objects can emit infrasound, something some horror movie music composers use to their advantage.

Filmmaker Gaspar Noe admitted in an interview that he intentionally used sound that registered at only 27 Hz, just above the 20 Hz limit for infrasound, in his 2002 film Irreversible. The movie is technically an avant-garde thriller, rather than classic horrorbut the intense violence, raw camera angles and disturbing images and content have made it dip into the horror movie category. The characters embody the monster-side of human behavior and indulge; youre bombarded with disturbing images of sexual violence, which understandably caused controversy, and the soundtrack intensifies this.

You cant hear it, but it makes you shake, Noe told Salon.In a good theater with a subwoofer, you may be more scared by the sound than by whats happening on the screen. In Irreversible,deep rumblings and a swaying, otherworldly grinding sound increases in volume, causing the viewer to feel dread just before extremely disturbing imagery begins. The 2002 movie Paranormal Activity was also rumored to use infrasound, though even if the deep rumblings in the film are above the 20 Hz threshold, they seemed to to a good job of unsettling audiences anyway.

Steve Goodman, in Sonic Warfare: Sound, Affect, and the Ecology of Fear, says that while the ways sound in media cause these responses in human perception are under-theorized, it likely has its place, especially with a source-less vibration like infrasound. Abstract sensations cause anxiety due to the very absence of an object or cause, he writes. Without either, the imagination produces one, which can be more frightening than the reality.

Sometimes using altered noises from everyday objects to get an infrasound-like effect can even save on production costs. Christian Stella, who mixed the score of the 2012 zombie film The Battery on a low budget, revealed on Reddit that he ended up using recordings of power transformers, air conditioners, etc, that I modulated to make deeper. Another part of the production team layered music on top of this to create the full movie score.

To manipulate the audience, Manfredinis process begins with viewing a complete or at least near-complete film. To help the visual narrative along, he remembers the actions, objects or colors that reappear and creates audial themes around the visuals. Later, he overlays tones, rhythms and stand-out sounds to evoke something weve seen, sometimes using sounds as cues, to drive home the otherworldly narrative we find ourselves in while we clutch our seats. In a sense, hes fooling the audience into believing that what were seeing is logical to the story were immersed in, and that we drew that conclusion first.

When he sees a scene where he thinks a special effect sound would work best, he works with the sound effects artist; then, he balances the effect sound with his score. If his sound is a low sound, I might go high, and vice versa. Visually if I see something very large the logical choice would be a low sound, and if it is small, a high one, Manfredini says. This is a departure from the horror movies of the 1940s and 50s, which relied on orchestral scores to fill in the silence. Horror movies today are more atmospheric, making the movie seem more plausible and causing a more direct sense of danger.

When we watch horror movies, were not meant to be simple spectators; we become passive participants. While immersed, we become convinced on some level that were there with the characters, walking around a dark corner or opening a door to a place we are definitely not meant to be. We might be safe in our living room while the monster approaches in the shadows, but the movie makes us believe otherwise. Its just a trick of the ear, though, obviously. Hopefully.

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how to remove fizz and harmonic feedback from amp sims

One major complaint musicians have against digital amp simulators is the audible fizz in the high-end frequency. Its difficult to explain through words, but if youre a guitarist who uses amp simulators, youll know exactly what were talking about. Its true that the presets on a lot of amp simulators can be less than desirable, which is why you need to do some tone-tweaking to get the most realistic sound possible from guitar amp simulators.

Another problem (though this isnt limited to amp simulators, but guitar amplifiers in general) is that you can get some incredibly loud feedback in two different forms the first is feedback hum, which typically comes from your pickups, and the second is harmonic feedback, which typically rears its ugly head when youre using high levels of gain/distortion and a high input level.

So to address the problem of fizz on the high-end frequency spectrum, first we should understand exactly whats going on here. Amp simulators produce a digital signal, whereas real guitar amps produce analog signal. Analog signal is sound the way Mother Nature intended it, pure and unfiltered. Digital signal is man-made representation.

For the most part, that fizz on high-gain amp simulators is the digital interpretation of harmonic distortion. Its true that you would hear some fizz if you pointed a real amp cabinet directly at your head and cranked the gain up, but its generally an airier fizz that can actually enhance recording. When a digital amplifier tries to recreate this fizz, it ends up being a wall of white noise that adds all kinds of resonance to higher frequencies, which sounds unpleasant because it isnt natural. What youre hearing is the unnatural simulation of natural high-gain fizz, in a nutshell.

To remove this fizz, what you need to do is set up your overall amp / cab tone first, and then use a parametric EQ to sweep for the offensive frequency, and cut it hard. For this step-by-step tutorial, were going to be using Reaper DAW with FabFilter Pro-Q 2, which is a paid plug-in but has a 30-day trial with all features. However, you can use whatever parametric EQ you want, if it allows you to do the same things well be doing in this guide.

Using your parametric EQ, sweep around the 4500 7500 kHz frequency range at around +24 DB. Its best if your parametric EQ has a frequency isolation button, so you will hear only the frequency youre searching for.

Another problem youll encounter with amp sims that have the distortion cranked up is really bad harmonic feedback. This will be in the form of extremely loud squeals whenever you mute your strings after playing for example, you play a chord, mute the strings, and your speakers scream at you.

The best remedy is to just lower the gain / distortion on the amp sim, but if youre intent on playing with maximum distortion, a peak limiter would probably help a bit (combined with the parametric EQ trick we did above).

You should know that a noise gate isnt going to really help you here, you need a peak limiter that will quickly attack frequencies over a certain peak. This is because a noise gate only eliminates static hum from noisy pickups, whereas harmonic feedback gets passed through as normal signal.

You wont be able to completely eliminate harmonic feedback when using high distortion, but you should be able to minimalize it without effecting your tone too much unless youre trying to play like Zakk Wylde and make lots of pinch-harmonic squeals.

FabFilter Pro-L comes with some good presets for exactly this problem, so adjust as necessary. But whatever peak limiter youre using, you basically want to try and recreate those loud harmonic feedbacks and keep adjusting the DB limiter in your plug-in, until they go away.

If the issue is with your Computer or a Laptop you should try using Restoro which can scan the repositories and replace corrupt and missing files. This works in most cases, where the issue is originated due to a system corruption. You can download Restoro by clicking the Download button below.

10 best ultrasonic bird repellents reviewed and rated in 2021

Or in any case, you realize that reflective rays and flapping sounds from scare rods, reflective bird tapes or other bird control devices are ruining your views integrity. If you are experiencing both of the mentioned matters, the best ultrasonic bird repeller would be your saviour.

This state-of-the-art device works silently yet effectively for casting annoying feathered creatures away. You are even not aware of the presence of this device or any track and sound of it in your living accommodation. This gadget deserves top prestigious stars from all customers.

The first marvellous ultrasound bird repeller should be put in your shopping cart is the Bird-X Ultrasonic Bird Repellent. This device produces high-pitched ultrasound waves of 15,000 25,000 Hz and periodic chirp sound to eliminate birds from perching and roosting.

This item comes with adjustable settings, which allow me to level up and down of my choice. Most of the time, I set it at Medium frequency, but I would love to move to a High setting when the mating season comes.

At first, I was quite sceptical whether this machine would work for pigeons as it produces high-frequency sound which does not belong to pigeons hearing range. It turns out the loud sound of 90 dB does a fantastic job. Pigeons feel annoyed and flee away once the sound is on suddenly.

Sometimes, we can hear the sounds inside our house and from the front yard. My teenie kids seem to be more sensitive to the sound, as they can hear the light beeping noise but do not feel overwhelming. By contrast, my middle-aged neighbors rarely detect the noise, and maybe it is due to their aging hearing loss, I guess.

This machine operates with batteries with A/C option, and it also includes a 15-metre cord to connect to the power sources. It would be more wonderful if it could come with the rechargeable solar batteries. But the extension cord is already a very good offer when I need to place the device outside, by the garden fence or on the roof.

The most convincing reason urging me to buy this product is that it generates the widest high-frequency sound range (from 13,500 to 45,500 Hz) out of all devices currently available on the market. It also means a larger variety of animals will be got rid of once the device is on.

The lowest setting could eliminate rats, foxes, and weasels. The middle level would be effective for stray cats, badgers, and skunks. For these two settings, I can hear the continuous pitching noise when standing within 1 metre around.

Lastly, the strongest setting, in combination with alarm and intense flashing LED light, would be a scary threat to wild animals, namely bats, birds, rodents. This highest level emits high-pitched sound over 24,500 Hz, which is far higher than humans auditory range. However, the alarming sound is still annoying to me.

This item is workable for a 90-square-metre area only, which is suitable for limited places such as a backyard or a small swimming pool. Thus, you should set this device right in the region where you do not any animals wandering around.

This item also wins my heart as it is powered by solar energy, as it works and recharges by itself without my notice. Besides, it does not consume any of my effort for maintenance due to its water-proof design.

This is a must-buy product to deter destructive animals away. Do bear in mind to set up the device under the sunshine, facing directly to the directions where unwanted animals come from for maximum effectiveness.

Instead of targeting many types of invasive animals like most of the current ultrasonic bird repellent devices, Bird-X has launched a special version, namely Pro Bird Repeller Version 2, that solely focuses on deterring woodpeckers and sparrows.

This model creates the natural bird sounds, namely alarming clank from birds of prey and the calls from natural predators of woodpeckers and sparrows. These moaning sounds go off every five minutes and they would threaten and alert smaller birds to fly away from the danger.

Amazingly, this model is ideal for large regions such as farms and fields as it can cover up to one acre. It is truly a powerful model producing 105-110 dB sounds, which are as noisy as the sound of a music concert and an ambulance siren within 1 metre radiant. These blaring sounds would chase woodpeckers and sparrows away.

One thing to be addressed is that the sound emitted from this model ranges from 3,000-5,000Hz, which falls within the auditory range of humans and woodpeckers. In this manner, we would hear the sound all the time from 100-metre distance.

The next effective bird repellent sound that I would love to suggest is the Bird-X Yard Gard. This product is ideally applicable to small restricted areas such as gardens, lawns, koi ponds, swimming pool decks.

The cogent reason why I make a purchase it runs with a motion sensor. Once any animals intrude within 10 metres, the machine detects the movement and gives off such threatening sound to ward off these animals. For me, it is a good feature as I do not need to hear the sound all day long.

This version does indeed eliminate a few types of birds away, but I realize that it works best for other ground, larger animals such as dogs, deer, raccoons. I must pay attention to the pet dogs in my neighborhood to see whether they are disturbed or not.

The next good point is the detailed sound levels. Normally, the other devices are categorized into low-middle-high or 1-2-3 level, thus I have to reread the manual to choose which level is workable for what kinds of animals. But this model paints another picture, as it takes me no time to adjust as the names of specific animals are already clearly painted around the button.

This product works on 4C batteries, which can last for about 1 month of constant working. The batteries are non-rechargeable, so that they will be replaced after a while. After a long time of using, I think the plugged cord would be the best as it remains stable and continuous working.

This model emits high-frequency sounds that do not harm humans, and sometimes I do hear the noise for several settings. And I found that if this model exposes to moisture in the air, the frequency will change accordingly and everyone can hear the noise from a distance of 20 metres.

One ultrasonic bird repeller does it work is the CleanRTH Advanced Ultrasonic model. This gadget catches my attention due to its triple scanned technology, which detects the body heat instead of body movement.

Firstly, this model works efficiently in a large region of over 1,000 square meters. It can detect the body heat within 35 metres in a frame of a 120-degree arc. If animals come from either side of the machine, it is still applicable. But always anchor the device facing towards directions where the unwanted animals appear.

This model is pretty flexible with separate functions, such as each sensor for strobe light and ultrasound, level of frequency, different sensitiveness (limit or extend the infrared areas). It is such a wise design as I can choose the proper function to blast birds away without interrupting our daily family activities during day time.

My relatives, who are in their middle-age years, feel nothing even though they are standing about 2 metres away from it. The troubles appear once I set a low-frequency level since the sound bothers my neighbors. So I prefer to set the high one.

Quite similar to the advanced version, this model performs 8 distinctive noises naturally recorded bird distress calls and predator calls to disorient, frighten pest birds away. I feel free to try all the noises to check which one works best for my current situation.

This mode allows us to activate calls in nonnumerical order, not in order from 1 to 8 as listed. I think it is a brilliant idea as birds sometimes get familiar with the repetitive sound, the unexpecting noise would chase birds away more efficiently.

I recognize that this version is most effective for starlings and sparrows as it produces 3,000-5,000 Hz sound, falling into the hearing range of these bird types. Apart from it, the loud blast of 105-110 dB makes pigeons warn pigeons of not coming to this protected area.

However, the wise cats would find other ways to approach the device from the back or climbing on the wall to avoid such annoying sound. I think it does happen to most of the devices, not only for this model.

I am not worried that the emitted frequency will be changed by the moist in the air, especially in the rainy season. After a long time of using, I realize that it works stably under any weather conditions, no matter what it is hot, foggy or pouring.

This product comes with 5 levels of ultrasonic waves for particular types of pests and animals. I also find it is a convenient product with an adaptable time setting, motion sensor, volume control for sonic alarm.

Generally, the alarm is loud as the frequency is within humans hearing range. But it depends on your age, hearing ability and space, so please try all sounds and levels to pick up the most silent setting for yourself.

This model can be run on 4C batteries for about a month, and then I directly plug in the outdoor electricity source. Unfortunately, the charger does not fit in the standard electrical box, as it is too big. So I have to look for a smaller adapter to connect to the energy. I wish the producer could fix this problem.

Another motion-activated bird deterrent that should be on my list is the Humutan Ultrasonic pest repellent. This one immediately catches my sight as it completely runs on solar energy and its ET-alike look.

This gadget work on a detection area of 110 degrees only, so it is suitable for a smaller place with erected fences and walls. To take good advantage of its infrared area, I place it in the closed corner of my fence, facing towards the main entrance, where the wild animals mainly come from.

I realize that this model produces 18,000-40,000 Hz, which is an ideal frequency for larger animals such as large birds. And sometimes, it works on house cats, dogs, several types of mice and rabbits as well. Red light and strobe light are also combined for increasing effectiveness.

One good thing is the passive infrared sensor (PIR) works quite well. It shortly detects the movement and triggers the ultrasound within a second, the strobe light and red light are activated right after that. I can see birds, particularly pigeons, flying away once the lights are on. Sadly, it seems not effective for squirrels and large dogs.

This product is mounted on the ground on top of a spike. The spike can be easily assembled from 3 separate parts. I am quite afraid of the plastic spike as it is thin and not that sturdy. I have no idea whether it can withstand strong winds or not.

This product is innovated with 3 sound patterns and 3 sound volumes with the same high-frequency for all. The recorded sounds are quite similar to squeak shriek noises, as they sound like the moan of animals get caught or hurt.

This noise waves disrupt pest communication and their feeding habits, which works best for bats, mice, and other insects. But my family is haunted by it. I am not sure that I would use it for the long term.

This product can cover a limited area of about 100 square metres, which means my whole house and a part of my garden. If I need to drive insects away from my garden, I should lay it by the window or stairways, facing toward the garden.

I think this model is ideal for small family use with not serious bird problems. Some people may find the sound is too loud, but the trouble will be gone if you place the device in a different room with your family rooms.

Lets put such noisy devices aside for a short while, here comes a portable spinning Bird B Gone Repellent. I have to emphasize that this model is not an ultrasonic pigeon repeller, as it uses the spinning movement to prevent birds from landing on the guarded area. It is appraised as an animal-friendly deterrent.

There are 4 suction cups in each corner of the base. I can mount them on the outdoor tables or decks to avoid the birds. These 4 cups gradually lose their strength to secure the device, so I have to replace them all after 3 or 4 months.

Amazingly, the device runs on solar energy. It is also equipped with 2 AA rechargeable batteries, but I can feel it is not as powerful as the solar energy does. It rotates slower in the mild day. I guess it would be useless when the winter comes.

A prerequisite criterion is to be aware of the actual audible ability of birds that you want to get rid of. Generally, the hearing range of birds fluctuates from 1,000 Hz to 4,000 Hz. However, the pest birds pigeons, house sparrows, starlings, seagulls are exceptions.

Several ultrasonic bird deterrents produces loud sound as well. Some can emit sound from 75 dB up to 120 dB within a metre radian. This roaring sound immediately frightens the birds and other animals, but it is a hearing-related danger to humans as well.

The high-pitched sound from the bird scarer might damage a baby s hearing ability. For several circumstances, women may suffer headaches, dizziness due to the ultrasonic sound as they are far more sensitive than men.

It should be noticed that home cats and dogs are sometimes terrified of the high-frequency and irritating sounds from ultrasonic devices. You should be cautious about installing ultrasonic tools in your area.

If you plan to protect an acre farm, you had better take a look at high capacity devices. But any gadget which could cover a moderate region of 30 metres square is a wise choice when you are living in a dense residential area.

You are also aware of the applicable infrared area. Imagine the device is the centre of a circle, the applicable infrared region is measured with the degree of an arc, where the sound can reach on either side of the machine.

Several devices works on angels of 100 120 160 degrees, thus anything not within this angle will not be affected by the ultrasound. It does make sense when some animals are free to reach the device from behind.

Most of the time, this gadget is installed outdoor, it may or may not close to the electricity source. That is the reason why you have to pick up the device with solar rechargeable batteries or direct charging function.

You may find several ultrasound devices equipped with a strobe light, distress calls and predator calls. If your wish is to eliminate grim birds such as owls, eagles, you may need further assistance from flashing light.

The length of the guarantee varies from branch to branch. And you may face some difficulties in finding the right place to fix it when any error happens. Do a search for warranty length and maintenance place once buying an ultrasonic device.

Sure is. This up-to-date device may be tagged in a higher price range than other conventional bird control techniques. You had better make a good comparison among current items on the market place, and you may work a savings target for later purchase.

As studied by the scientists, the human can hear from the lowest frequency of 20 Hz, which could be the sound of a heartbeat, the ticking sound from the clocks hands. People can handle the sound of 20,000 Hz without discomfort in our hearing ability.

In terms of loudness, humans, generally, can hear sound from 0 to 85 decibel (dB). The normal speech marks at about 55 dB, and the annoying sound from heavy city traffic reaches 85 dB. It is dangerous if people are exposed to such loud sounds in a prolonged period.

Ultrasonic bird deterrent emits the sound with the high frequency and certain loudness to chase birds or other types of unwanted animals away without negative effects on the humans audible range. The high-pitched sound is far from the audible range of humans, but it falls within the hearing capacity of several types of birds.

However, it should be noticed that the factual hearing range of humans varies by age and gender. Some women and young children are unexpectedly affected by the ultrasound. For the middle-aged or the elderly, some might not hear the ultrasound due to the hearing loss.

It produces the sound of high frequency ranging from 15,000 up to 30,000 Hz, which may annoy or trigger the nervous systems of birds. They also realize the sound as a warning from their predators or an alert of territorial violation so the birds would not come close to the guarded area.

This gadget can be used to avoid unwanted birds in human habitats such as residential areas, city squares, or in wild spaces like farms, cultivated fields. This book-sized machine offers huge comfort to humans life.

Ultrasonic bird repellers can be categorized into outdoor and indoor use. Indoor devices are sufficient for the familys use and small houses. Meanwhile, outdoor gadgets are perfect for front yards, gardens, farms, and fields.

The first 2 levels are audible for humans too, so you have to be cautious when installing any devices in crowded regions or any newborns are around. For the highest level, most of the humans, except several special teenagers, cannot hear the sound, but it would threaten your home dogs and cats.

In terms of kind of sounds, some devices are recorded with natural bird predator calls, distress calls, or the groaning noise of animals. These sounds are the best tool to cast birds away, but people may feel frightened and haunted. Other devices produce chirping or clanking sound only.

There are dozens of types of bird repellent devices on the market place, some of them are traditional methods yet still being sold out shortly. However, the ultrasonic bird repeller is truly the most sought-after product due to several primary benefits that it has brought to the customers.

It is no doubt that the scary sound from ultrasonic repellent terrifies birds from a distance, thus these aggravating feathered creatures would not prowl your garden and guarded regions. Additionally, it also brings out prompt results, and I bet that you would not see any birds after 2 or 3 days of using.

The warranty is different, ranging from 6 months up to 2 years, depending on the warranty policy of each manufacturer. You can easily find this policy on the producers website, information box, and the manual instructions coming along with the device.

Flat surface: no matter where you would like to secure this machine, you had a better look for a flat surface that suits the flat base of it. Ultrasonic bird repellents are often in book size, and you would not get into any difficulty in finding a perfect surface for it. The most popular place for installation is the walls, roofs, fences or on a big tree branch.

Near the energy source: if it is a solar-battery version, it should be installed right under the sunshine without the shadow from nearby screens or trees. However, when it comes to a USB charger, you should consider the wire length and place the device near the electricity source.

One of the reasons I would like to recommend you to purchase the ultrasound bird deterrent is that it requires the least cleaning and attention compared to other bird control devices. As the device is made of durable plastic, it can stand for a long time under any weather conditions.

Far beyond other conventional bird control tools protecting a tiny space, a small ultrasonic bird deterrent prevents feathered intruders from a distance. The birds would recognize the sound as a source of danger so that they would not get closer to it.

Jerry Jernigan, Thank so much for your complete and detailed information in your coverage about birds repellents. So for a small balcony in a fourth level and exclusively pigeons you which one you recommend me please.

What would be your recommendation for the best ultrasonic repeller for swallows? Were having an issue with nesting in the soffits of our churchs steeple and would like to look at ultrasonic options before we try netting.

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high pitch sounds | free sound effects | sound clips | sound bites

Super high pitch dog whistle sound effect for 30 seconds. This file is super high pitch and your dog will hate you if you play this for too long. May be a great sound weapon for pest deterrents as well. Can be used to ward of mice, rodents, rats, stray dogs, stray cats, and even keep your street free of unwanted bums, beggars, hobos, etc :) See the 10 minute Dog Whistle Sound video. Very annoying.

A mosquito ringtone 11kHz. Nice to put on your phones or computers and piss people off with. They wont know where the hell its coming from. Very high pitch ringing sound, sounds just like that ringing you get in your ear sometimes. Nice for pranks.