I have found they (large flat screen rear projection TV's with 3 CRTs inside it) have some nice Gold plated boards, some Cast Ali (inc liquid goo oil!!!) Lots of wire and a 'front Silvered mirror', I have not made use of one yet, I one day will make a 'true mirror' one day....
The rear projection LCD, nice boards.. Wayyy too many screws around lots of resin molded plastic.
Some nice stuff inside where the mirrors, lenses and prisms are. These have hobby
escrap jewelry written all over it.
Lots of thin plastic coated wire. Big prices of plastic.
I don't think there's Fresnel lenses in these all all, just the white diffuser sheets and a clear lined plastic sheet that sorta does look like a Fresnel lens, but isn't.
I got a real Fresnel lens of a friend who brought it at a garage sale. It is a 'Magnifing lens to turn a 14 inch TV into a 25 inch TV'.
That's where I think the confusion comes from.
That Fresnel lens is deadly....
It can defiantly heat mince pies, it will make something smoke in a few seconds, you just have to get the focal point right and 'bam' smoke. Don't put your hand behind it.
You need a proper safety welders Helmut to get the focal point right.
Or if you made a proper jig to set it up in, and a secondry device to aim it at the sun all the time, you could cook food or heat water or start fires quickly.
It pretty shocking how much energy there is in the sun and how we do not utilise it.
I had a play around with it, and a couple of smaller ones I got at a 2$ Asian shop. They were sold for 'reversing lens' to magnifiy a rear vision mirror in a car, for parking a van etc.
Though I have a nice little arc of burnt car seat where I left the lens off a 3CRT rear projection TV on my passenger seat one sunny day....
It follows the suns movement and intensity over a full day..
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