You should find this link interesting, if you live in an affected area try listening on a scanner too:
www.ofcom.org.uk...
Mystery as car alarms go haywire
Car alarms and central locking systems are being sent haywire in the Black Country by a mysterious radio frequency blocking their signals.
In two neighbouring streets dozens of bemused drivers have suffered with the fault, with some spending days locked out of their cars.
Communications regulator Ofcom has said the problem also affects other areas and says it will investigate following complaints.
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