ASPECTEK Includes AC Adapter, Extension Cord Pest Repeller Yard Sentinel 2 Pack Outdoor Ultrasonic Animal Control, Green, Sound Frequency:15 kHz -18 kHz

We had been unable to use the patio surrounding our home because of bird droppings which we only discovered shortly after moving in. The prior owners must have washed down the decking every time they were going to show the house. Yuckola. We still take our shoes off after coming in the house just in case. We were feeling a bit desperate; the gorgeous trees add a lot of privacy which we are loathe to give up. This machine seems to have worked on the doves as well as the large black birds (crows?) we had been getting. We have this mounted to the eaves of our house which puts the machine at about level with the lower third of the canopy of our very large fig trees. Per the owner reply to our question that positioning should work as the machine covers a 70 degree arc up and down (presumably a 140 degree arc total). We turned the dial to the right just short of where birds/skunks transitions into cats/dogs and it does seem to be working. It's been 72 hours thus far and no more bird droppings. We had been really frustrated and skeptical after we tried the reflective strips and other visual cues to scare birds away because they only seemed to work for a week or two. We've had this up for 72 hours so far and as of this morning, we are giving it 5 stars for being incredibly effective. Will update in a few weeks with additional results.=================UPDATE 1: First week of use:This machine continues to be effective and humane; and it has made us much happier with this home we recently purchased last fall. We still see birds flit by and maybe even come down to grab twigs for nest building but there are NO MORE huge piles of messy droppings littering the deck every morning. We still get hummingbirds for the flowers, but again, no nesting. All we see now is leaves and twigs which are easy to sweep off and much much much cleaner. This machine is perfect for what we need. We've kept it on the same continuous and ultrasonic only setting just short of where birds/skunks transitions into cats/dogs and the audible noise volume is turned down to zero. We thought we would have to work our way down the spectrum every 3 or 4 days until we found the right setting for the local birds here, but it looks like we got incredibly lucky and hit the correct frequency on the first try. Will update periodically after several weeks and then several months of use with progress updates. If all goes well, we will be recommending this to friends who are getting bird strikes on their windows.Bottom line: Continues to be a 5-star solution. Confidently recommended for overnight bird roosting and nesting problems.=================UPDATE 2: First month of use:Well, we've had some ups and downs. We decided to try changing the frequency to see if we could get an even broader effect so that pigeons would not even land anymore to get twigs as we were getting the occasional dropping on the deck just from that and it turned into a disaster. After just 24 hours of the changed frequency we started having problems again. Then we changed the frequency back, but it turns out that we had left it unplugged during the change back to the original and forgot to plug it back in. Our deck was a mess. The whole thing had to be hosed down again. And we washed off all our furniture, etc. That was horrible. After we plugged it back in, the droppings seemed to reduce by a lot - about 80% over night; and then completely stopped after about 48 hours. We cleaned everything yet one more time and fingers crossed we've been good ever since. And curiously enough, even the occasional landings seemed to have disappeared. Maybe its because when we made sure the frequency was set for the third time, we must have tweaked it just enough to be perfect. So that was overall a huge win.Now however, we have some new smaller bird that seems to be flitting around and nesting at the margins of our deck - or at least that's what we think from the teeny tiny pile of bird droppings. Still gross but a better problem as the sheer square footage involved is smaller and in an out of the way corner of the decking we can clean more easily. So after some discussion, we've decided to leave the first unit alone as it's working great. We had our first rainstorm and the box is mounted on the eaves where it still gets direct rain and run off from the roof as well and it's still working great.To figure out this other smaller problem, we're going to purchase a second unit and set it at a different frequency to see if that works. Hopefully the new ultrasonic frequency won't cancel out the old one. Will keep this posting updated.Bottom line: Continues to be a 5-star solution. Confidently recommended for overnight bird roosting and nesting problems for doves and large blackbirds and some other large bird of some kind. Purchasing a second unit to experiment with another frequency for smaller birds.=================UPDATE 3: Full 90 days of use: Make sure all angles are covered!After some accidental re-alignment we figured out that the problem we had been having with smaller birds was due to occlusion and not the frequency; so all of the birds species - large and small - are driven away by the same frequency (continuous and ultrasonic only setting just short of where birds/skunks transitions into cats/dogs and the audible noise volume is turned down to zero).These units work on line of sight so obstructions near the unit can block the coverage area farther out and birds find these safe zones and roost there. We used the second unit then to generate a cross hatch coverage perpendicular to the first unit at the same frequency. The area we are trying to keep clear is about 50 ft deep x 80 ft wide, surrounded by trees about 30 - 40 feet tall. Both units are mounted about 10 feet off of the ground pointing straight out. One unit is mounted at the center of the 80ft wide section. The other is mounted at about 10 feet in from the corner along the 50ft deep section.For us the results were immediate. The resulting invisible cross-hatch of ultrasonic sound is incredibly effective; overnight the deck was completely clear for the first time ever. We are extremely happy to have a droppings-free deck to enjoy year round. This product has made our yard usable.

I’ve been trying everything for years now to keep the birds out of my blueberries and the deer from destroying everything in my yard. There is not a spray, scent or decoy that I haven’t used. So I bit the bullet and bought 2 two packs to use in my yard.What I found was that they are easy to setup and seem to be pretty sensitive even at a lowest setting. What that means for you is that unless you’re using the plugin adapter, you’ll need stock in C-cell batteries. Last about three weeks max as the are constantly going off every time anything moves in the yard (leaves, you or anything else). I tried the settings with and without the added screech of a bird which I think would be better if it was a human voice or dog barking, but it was pretty annoying since it was constantly going off in 4 different areas of my yard all day and all night.So how did it work? Well if you consider that deer stood 10’ away from it while it was screeching, creating high pitched noises and a red light and the deer continued to eat my trees and plants. Didn’t bother them in the least.Birds, flew and ate berries on the bushes right in front of it as it was working. Needless to say, for me, they didn’t even bother the pest that I have. Very disappointed that I purchased these and wish that I’d saved my money, but getting really tired of the constant fight and destruction of my property.I live in the country, but near neighbors who feed and cherish the deer, so maybe the only thing left for me personally is the physical removal of the deer as they are nearly tame around here (until hunting season starts then they’re nocturnal), so if you are in the same situation as me, save your money as they are like everything else that just doesn’t work.

I bought three of these several months ago to scare off deer and racoons that terrorize my shrubs and garden. They seem to be working. I use the ultrasonic and sonic features with the motion detection option. I have no idea if the ultrasonic feature works . . . it's ultrasonic! The sonic feature definitely works! Loudly! Persistently! Just ask my neighbors. If the animal (or human) motion continues, the sounds cycle through a siren, a loud siren, and something like a really angry screeching eagle. There is a volume control, but if you want the sounds to be heard outdoors, you'll need to crank the volume up to high. The motion detector and the sounds work. Vertical and horizontal coverage is quite good. I've seen deer, squirrels and a raccoon venture toward my large garden in the back, trip the motion detector and freeze when the siren/screeching starts. Then they leave. Because of the distance of my garden from an electric outlet, I've been running these on batteries. Buy many, many batteries. With normal use, they seem to last maybe two weeks. And, each unit takes 4 of them. So, it's pretty easy to operate; it's very loud; and it seems to work. But, it does chew up batteries. One other inconvenience: all controls are on the inside of the unit. Once they're set, you have to snap on the not-real-easy-to-snap-on back panel, all the while the unit has sensed you and is already screeching. I'd still buy another one. Nothing else has seemed to work.