The DUALTEC explained ...PIR, MICROWAVE but WHY? (movement detector)

For 40 YEARS I've been working with PIRs and Dualtecs.
But why are Dualtec's so popular?
Here I explain what they are, how they work and WHY we use them for intruder alarms.

GEMINI VIDEO COMING SOON ###

INDREK TELEPHONE VIDEO:
   • Arduino powered old rotary phone  
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Explained so that ANYONE can understand it, it's another QUALITY video from the mrmattandmrchay channel.
Thank you for watching!
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  / mrmattandmrchay-110000184094857  
Please give us a 'like', thank you! :)
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IMPORTANT NOTICE ABOUT SAFETY AND YOUTUBE:
The mrmattandmrchay channel is a RESPONSIBLE and RESPECTABLE channel.
I do not promote or glamourise dangerous activities on any of my videos.
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THE MRMATTANDMRCHAY CHANNEL, established 2008:
I'm passionate about uploading quality and interesting videos for YOU, my audience.
What is my channel about? "Old lift machinery made interesting", old air-raid sirens, prehistoric alarm equipment. If "I" don't find it interesting ...then IT DOESN'T GET UPLOADED!
I always spend a lot of time editing my videos with animations, video in-sync with music and voice overs to make them this way.
My moto - "Quality NOT Quantity" - this video took 2 MONTHS to edit!
But without you, I'm nothing here. Thank you so much for watching.
...mrmattandmrchay is me (Matt) and my son Chay.

THANK YOU very much for watching :)