Having lived in Truro Road for the past six years I am familiar with the sounds coming from our local train stations. However in the past 3-4 months a new, invasive noise has started and I don't know where it is coming from. It is loud in our garden and the back rooms of the house (which face in the direction of Alexandra Palace).
It is a high pitched whistle on one continuous note, and happens intermittently day and night for very long periods of time. Sometimes the note drops down to a lower one before going up again.
At first I thought it was from local building works but it has been going on for so long now I am concerned it is a permanent fixture. Please can anyone advise where it is coming from and what to do about it, as it is problematic for us.