So as you will be aware it has been noted now by a couple of Amateurs in my area, myself included, that there is a strange 'werewolf' interference coming from the local Tesco store here in Catterick Garrison, the cause of this remained a mystery, until now.
A colleague of mine figured it could have been a combination of the automatic doors and the 2-way radio systems used by the staff, however I have narrowed it down to solely the automatic doors on the front of the shop as after 4pm on Sunday night, the interference vanished.
Then to add to my theory of it just being the automatic doors the 'howl' part of the interference coincided with the doors opening on approach of someone, therefore the case is now solved and it stands to reason that the automatic doors at this Tesco store fail to comply with the regulations in place regarding generation of interference, and because they cause interference into spectrum where Amateur radio operators are primary users, that could be a problem for the automatic door manufacturer if other doors of this type are found to do exactly this, especially if that interference is found in bands used for more critical applications.
A video will be released on YouTube later today or tomorrow morning.
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