ASPECTEK Yard Sentinel Ultrasonic Animal Repellent, Waterproof Ultrasonic Cat Fox Repeller with Motion Detector, Pet Dog Deterrent, Rabbit Rat Scare for Garden Yard Field Farm, 4 Key Remote (UK Plug)

After having problems with crows/rooks and one particular small bird attacking my chimney stack, I ordered an ultrasonic bird repeller from Pest Clear. As that unit produced intermittent sounds, I bought another, so had two in the loft of the roof. This helped to clear the crows and & rooks away, until this spring in 2018.So realising that I needed try additional measures I had no choice to look around for something else. When I say I have no choice, these crows and rooks come to the chimney stack and vandalise it. At varying times from 6am to 7am in the morning from their roosts, they arrive at the chimney pots. There is this ‘bang, bang’ on the brick work as they fervently attack the chimney stack, then then follows crumbling noises and brick dust and pieces falling down the roof. If it wasn’t so serious, to see the damage of the first two rows of brick damaged in that chimney stack, one could relate it to the crows stealing Father Jacks glasses in Father Ted series, or more ominously the film the ‘Birds’ by Stanley Kubrick.So, initially I bought two units of the Yard Sentinel RC Ultrasonic Pest Repeller, setting BOTH to constant, full volume and then put them up in the loft of the roof as I had done with the ultrasonic bird repellers from Pest Clear. . After a couple of days, the neighbours thought at times there was a burglar alarm going off. MORE importantly it scared off these large birds, the crows and the rooks.Each unit goes through a cycle of emitting a variety of sounds, at different frequencies. Sometimes there is silence, so that can be the moment that crows and rooks WILL come back. The crows and rooks are smart, they are persistant as they fly around locally from tree to roof top, etc. Whilst two units could adequately complement each other during those quiet periods, I also knew that the crows and rooks COULD become immune to even the noise from two. So I ordered an additional four units, making SIX altogether in my armoury.SO, in order NOT to annoy or concern my neighbours, THREE units are positioned in one chimney, just above the fire place and another two in another chimney, in a similar fashion (It wasn’t big enough for three). Consequently I have one in reserve. I don’t use the fire places, so I can put these in the chimney safely. I have placed them in the upstairs fireplaces, rather than the downstairs fireplaces. The noise goes right up the brick chimney, to the chimney pots at the top.Trying to break the habits of the crows and rooks was never going to be easy, so I am NOT expecting instant results of them NOT returning. They keep coming back, BUT the noise drives them away AGAIN and AGAIN.The racket that FIVE of these units produces, on a 24 hour constant, FULL volume setting is detering the crows and rooks. It drives them off the chimney stack by giving them an enormous headache... I have read some of the comments from purchasers who state that these units don’t work. They do, it is just that you have to be persistent with using them and IMHO, understanding that you may need more than one...The crows and rooks keep returning, BUT they don’t stay VERY long. Eventually the crows and rooks pattern of behavior, their 'habits', will be broken, so they don’t visit my chimney stack any more. In the end they will forget about it and fly somewhere else. That is how you break the behaviour of anything bullying you, they FORGET about you and don’t bother you ever again!It is an unusual situation to be confronted with, BUT with these units, I believe that I am GOING TO WIN.

It does it very good job of keeping the hordes of pigeons off my garden, the remote control is very handy & constructed better than most car ones. The only (huge) fault I have it with the real clip on cover, they really need to re-think this, no matter how well you fit it the likelihood is the unit will fall off the back & break. I have done a fix by fitting two long cable ties right round the unit. I should not have to do this with a new product.

What a useless item it’s on its highest levels to get rid of cats fouling our garden and they still foul it when this so called repellent is suppose to get rid of them ha ha ha so guys don’t buy this rubbish

There is a cat that visits my house daily and upsets my cats. I wanted something humane to keep it away so bought this.First thoughts: cheap looking but I didn't buy it for looks. Very easy to set up and get working although the back of it is a real pain to put on. The remote control works OK, even from upstairs.Just a shame it didn't keep the cat away.You can set frequency range and behaviour. Unfortunately whatever I chose had no effect on our unwanted visitor. None at all. It didn't repel my two cats either when accidentally left on, they ignored it completely.Basically, all this box did was make noises when the postman came to my front door.I don't recommend it.

Works very well - very satisfied

It is great it doesn’t need charging, unlike those solar powered ones. But I am not sure if the ultrasonic noise works on cats, my neighbour’s cat keeps visiting our garden during the day. But at night, the flashing light seems to get the cat’s attention and scared it away. I tried tune the frequency of the ultrasound, it is either too low and I and my children can hear it and put great pressure on our ears, when I turn up the frequency until I can’t hear it and seems cat can’t hear it either … I got a iPhone app and detects the ultrasound frequency at about 19k. It is extremely hard to find the right frequency to annoy the cats away without annoying the people. So far I haven’t, neighbour cat visited twice today and not even look at the direction of the machine. Any suggestions?I bought two of these but the dials of the frequency and the volume are at different starting points, that makes difficult to adjust the second one after setting up the first one.Another issue with the machine is that, after heavy rain, the water got into the light housing cover. Although the lights still works, but I am not sure for how long. Is this by design? I doubt it though. When the light stop working I bet the night would become useless.

It’s the adaptor, in my experience, which usually malfunctions before the sentinel, but is not available to buy separately. It should be, to avoid junking something that still works. Save the planet, etc,.

The sentinel was perfect for settings, there are so many to give you complete control of the device. Unfortunately as said by others its let down by very poor design; the cover does not just 'slip' of as stated in the instructions, I struggled to get it off when it first arrived. After installing the supplied screws to a wall I could not get the cover back on to the unit. I'm no weakling but my hands were stressed after 30 mins of trying to put the cover back on. I gave up until the next day to let my hands recover. By this time the unit was looking damaged where the plastic had been straining to get the cover back. Come on, surely a clip system would have been easier and give better water protection, I'm not sure how long this will last outside given there is no seal.