America’s most advanced ultrasonic outdoor pest repellent is now available in Australia! The Yard Sentinel offers innovative pest repelling technology that repels pest birds and animals by targeting their main senses: the four predator sounds target hearing and the ultrasonic sound targets feel. This way, you can chase away birds and not be worried about your bank balance. Warranty and Maintenance The individual speaker blast time which determines whether the sounds have a "rat-tat-tat" or long "boom" effect The Yard Sentinel features an adjustable Passive Infrared (PIR) motion sensor with Night Time Scanner technology that senses motion from all directions up to 45 feet (13 metres). The unit responds to an intruder by emitting a high frequency 120 decibel sound blast. Ultrasonic blasts at high frequency are intolerable to most pests. one scaring option are offered with up to 4-speakers and normally supplied with approximately 100 foot of cable per speaker. The ‘Broadband Pro’ ultrasonic/sonic

Most of the time, this device emits high-frequency sound, which is not within the auditory range of humans but falls in the hearing capacity of the birds.

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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. We work together to create a safer environment for both humans and wildlife, unlike other harmful pest products we give you 110% of our products to their best value making sure they are safe and efficient to use for everyone. The BirdStoprepeller is not 100% waterproof and needs to be used with the guard/ cover that is supplied with it.

The main reason why the Sentinel ultrasonicrepeller stands head and shoulders above other models is because the frequency is adjustable. The user can very easily adjust the sound to get the optimum effect for the animal you are targeting .And because thefrequency of the ultrasonic unit is adjustable, it can also be made to repel rats, mice, squirrels, foxes, birds, badgers etc, Please note that the Sentinel deterrent can only be set to repel one animal type at a time. In other words, it can't repelcats andbirds at the same time because animals have different hearing ranges. Another major consideration when siting a sonic device is proximity to human habitation. The benefit of a fully programmable device is that the various sounds

DEFRA’s view:

Here comes another portable bird control device for your family. However, its efficacy is sometimes affected by the moisture in the air. 5. Cleanrth TSBR620 Super Advanced Sonic