https://www.youtube.com/watch?v=z20RJq8EH2c
One of the better ones for Huygen’s Wavelet Principle. From: Brian Webster Sent: Thursday, September 28, 2017 4:47 PM To: af@afmug.com Subject: Re: [AFMUG] Multipath fading for a laymen (visuals please) Sure it will, take a single bulb flashlight and shine it on the wall like this attached image. Do you see the light and dark rings of light? The bright ones are odd number Fresnel Zones, the dark rings are the even ones. They are dark because they are 180 degrees out of phase from the odd zone and thus cause cancelling and in the case of the light rings they are darker. Much in the same way you get reduced signal levels. This is why it is always preferred to engineer radio links at a height to only expose the first Fresnel zone and block the second zone. It mitigates or reduces this phase cancelling and signal reduction. Thank You, Brian Webster www.wirelessmapping.com www.Broadband-Mapping.com From: Af [mailto:af-boun...@afmug.com] On Behalf Of Steve Jones Sent: Thursday, September 28, 2017 9:04 AM To: af@afmug.com Subject: Re: [AFMUG] Multipath fading for a laymen (visuals please) Light wont cancel On Sep 28, 2017 7:02 AM, "Josh Reynolds" <j...@kyneticwifi.com> wrote: I don't understand why you can try to come up with examples around PSI but light and pictures are hard. "Hands on" kinda guy, eh? On Sep 27, 2017 10:51 PM, "Steve Jones" <thatoneguyst...@gmail.com> wrote: If i punch water (giving it a hypothetical 2d plane) with 360 psi pressure, it should send 1 psi out in each 1 degree? Correct? Each x distance of water absorbs y of that 1 psi? Say its 1psi per inch som meter would measure 0? 1/2 would measure .o5? On Sep 27, 2017 10:45 PM, "Steve Jones" <thatoneguyst...@gmail.com> wrote: Chuck... make a water video. On Sep 27, 2017 10:38 PM, "Chuck McCown" <ch...@wbmfg.com> wrote: Oil film on water. The colors are due to cancellation of some wavelengths. https://en.wikipedia.org/wiki/Thin-film_interference From: Steve Jones Sent: Wednesday, September 27, 2017 9:05 PM To: af@afmug.com Subject: Re: [AFMUG] Multipath fading for a laymen (visuals please) Ductings easy, i can put it through a duct, if need be i make a duct out of ice to show the temp and humidity. I can show noise with a bright light close and dim light far But how do i replicate cancellation. I assume water, but timing the ripples might be an issue. Anybody have a reflective ripple cancellation to still water video? That would be the bees knees. On Sep 27, 2017 10:00 PM, "Josh Reynolds" <j...@kyneticwifi.com> wrote: "Sometimes the wind blows and the leaves move. This changes where the light moves." Almost everything in RF can be visualized with light. Some things are harder than others (ducting for example). On Sep 27, 2017 9:49 PM, "Steve Jones" <thatoneguyst...@gmail.com> wrote: Laymen, laymen, laymen. How do i visualize the fact that the same thing at the same level, can cancel itself out? Beyond that, how do i show the variance factors, temp, humidity, radio mites? Even better would be a live display of reasonable things they understand. My old man would be easy. Id smash his right index finger, then smash his left, hed understand because his right finger quit hurting so much. But i assume the soft people of today that wont work, theyll just talk about how bith fingers hurt On Sep 27, 2017 9:41 PM, "Jaime Solorza" <losguyswirel...@gmail.com> wrote: Use an adjustable beam version...good way to visualize On Sep 27, 2017 8:28 PM, "Josh Reynolds" <j...@kyneticwifi.com> wrote: Shine a flashlight through a bush. If you're lucky sometimes the light reflects off multiple leaves onto roughly the same spot. (Constructive reflection) On Sep 27, 2017 8:43 PM, "Steve Jones" <thatoneguyst...@gmail.com> wrote: I have a location thats solely down to multipath reflective fading. The best analogy i have is noise cancelling headphones, which makes total sense to me... but still the same dull look. Is there aome rf for dummies visuals?
