In The Straight Dope article entitled, “Do ultrasonic bug repellers work?” at:
Cecil asserts that “ultrasonic mosquito repellers all have one thing in common: none of them work. At all.” This isn’t necessarily true anymore. According to this article:
A fifteen year old boy invented a ultrasonic mosquito larvae killer. It works by transmitting the resonant frequency of the mosquito larvae’s internal organs, bursting them open and giving the pests what they deserve!
A $4000 machine that you have to dip into standing water within about 18 inches of where mosquito larvae are growing isn’t exactly the same thing as a “repeller” for the flying adults.
What about the rodent repellers? Someone please tell me that these things have some effect (other than placebo for my frazzled nerves). I have a few in my house. We had a couple of mice after a holiday last year and trapped them. I bought a few plug in things and we haven’t seen one since. Is this just coincidence? Now I’m all scared and the evenings are getting darker…
A lecturer I had in Psychoacoustics said that the frequencies used, at least in the big warehouse repellers, are effective because the rats/ mice find the loud (to them) noise unpleasant, scary and possibly even painful. Is this completely untrue? Please, someone just lie to me if necessary…