Cost ★★★☆☆ (See cost here)
Source Local hardware store / Internet
BIRDS SEEM UNAFFECTED as the sound range is outside of the hearing range of birds.
When the motion sensor is triggered on the repeller, it activates an ultrasonic sound which is used to deter unwanted animals.
The sound frequency is supposed to be outside of the human range so that you and I can’t hear it, although a lot of people are saying they can hear it when its working (especially younger people). When it goes off it sounds a little like a cicada.
The unit is 3.5 x 6.8 x 5.2 inches (Similar to a CD case in size except a bit thicker). It is easy to move around and set up. Just put it where you want it and turn it on.
** Birds seem unaffected as the sound range is outside of the hearing range of birds.
There are Keyhole slots on the repeller so you can either sit it on something, or hang it up on a wall.
You can use batteries to power the unit, but if it is working a lot (the ultrasonic sensor is getting activated a lot) then it can chew through batteries. It also comes with a power cord if you are going to put it near a source of power this option is advised.
*Limited effect on birds.
The manufacturer says “Maintenance-free and weatherproof”, however you may not want to put it out in all the elements, as some people have said that water has got into it, rendering the unit useless. Placing it off the ground and under some kind of cover is advised.