Database of interference sounds and devices
In each case click the graphic to hear a sample of the QRM
BT Vision Powerline adaptor 3-30mhz notched in some ham
bands reported range 500 yards. UPA Type (Universal Powerline Association)
Advent HPA (Home Plug Power Alliance) type powerline adaptors as sold by PC World, range three
houses click pop when idle, louder and faster when in use.
2-22mhz no notches noted.
SavaPlug
from Iceland and other stores, reduces power consumption of
fridge freezers quite old tech now, QRM from 240khz to 600Khz
some harmonics also. (in house)
Defective street
light (not as shown) QRM 100 kHz to over 32 MHz 200 meters range
Mains powered
(12vdc)ultrasonic cat deterrent, very local cure by adding earth
spike to negative wire. Frequency range 10-30 Mhz
Alba TV/DVD on standby affects 9- 11 Mhz range 100
feet, cured!
Cure with TVI Filter as shown 
Fits between TV and
antenna.
Electric fence, range 400 yards worse at night. The sound clip was made at 400 yard range, close up its a very clear noise. Cure by asking owner to check connections for rust and to make sure weeds have not grown into it. Point out fence will work better as well! Cured!
