It’s indeed an amazing image and to think we have it because a guy with fabulous sides glued a emergency blanket to an umbrella makes it even better. Has a good story attached to it.
Congratulations, you have recreated the type of folding satellite dish that was used on the surface of the Moon by Apollo astronauts, to return live video to Earth. The ability to fold, portability, light weight, and ease of setup was very important to them... and they didn't have any wind to contend with. Impressive results! You might get better reception if you can find an umbrella with a center "handle" made of fiberglass or some other dielectric. I have a feeling that the aluminum handle on yours may be doing your yagi no favors. Very cool video.
@@Crazen2the conspiracy theory is cover up for the fact that NASA funded the missions by letting Stanley Kubrick shoot his films in space to save on special effects costs.
What i always wonder is why they would need to fake it? I don’t see the point. Also don’t forget that at that time the Soviets where also pouring a massive amount of funding in their space capabilities. And ofcourse in intelligence. Combining all that the likelihood of the Soviet Union finding out if it was fake in a 20 year span is not that unlikely. That would have been major.
I still have a few emergency blankets from the 90s they have much a thicker metal layer. its so thick it can block all signals when I wrap my phone into it
One way to cut mylar coated plastic foil is by sticking a bit of copper wire in your soldering iron then dragging a u-bend of it across the top of the foil. I use that method for both cutting and heat fusing mylar for blimp envelopes. Or just use your normal soldering iron element held at a slant if you don't mind gunking it up.
So they make higher end photography umbrellas that use an aluminized Mylar lining. That would work better. The other ones are just shiny(ish). They and most “metallic” spray paints use garnet dust for the shininess.
Garnet dust? I don't think garnet dust is shiny - it's basically sand (ground up garnet rock). It's what you use in sand blasters and waterjet cutters. It's not shiny, it's usually red
@@gorak9000"Garnet" covers quite a wide range of crystalline materials, some of which can be opaque and some can have gemstone-like transparency. e.g. YAG (Yttrium Aluminium Garnet) was used as a low cost diamond substitute in jewelry before cubic zirconia, and is used today in lasers and fibre optics devices.
@@ferrumignis Interesting. I never knew what the G in YAG stood for. I think it's also used in microwave RF components - filters and couplers or circulators. It has some unique properties! I didn't know being reflective / shiny was one of them! Or maybe that's YIG, and YAG is mostly for optics / lasers
@@gorak9000 In addition to being a very hard material, garnet is a beautiful gemstone that comes in a variety of colours. Interestingly, for centuries, it was believed that garnets came in all colours except blue. I believe blue garnets were recently discovered, but I could be wrong. Also, an alternate name for garnet is carbuncle. And that's why the titular 'blue carbuncle' from the Sherlock Holmes mystery was so special!
I think you could just put the space blanket (or other metallic layer) on the outside of the umbrella. Your first experiment showed that the umbrella cloth is rf transparent. It may be easier to fold down the umbrella if the metal's on the outside - less harsh angles when collapsed. Plus it should be easier to apply since you don't have to work around the spokes.
Maybe a metal anti mosquito mesh would also work, but IDK about the holes in it. The advantage of it is that you can sow it into the umbrella and that it being a mesh makes it actually bendable.
Wavelength at 1.7GHz is 17.6cm, and to be effective as a reflector the holes must have a diameter well under 10% of the wavelength (1.76cm or very approximately 2/3 inch). If your mosquitos are bigger than this I want nothing to do with them 😂
@@ferrumignis I've seen mosquitos that large, but they don't bite and are quite funny to watch trying to evade you. They are unbelievably flimsy and clumsy
Awesome stuff. Beyond the extraordinary astrophotography that is in reach of most these days is planet sized collaborative interferometer astro radar. Time to make it happen.
Great video as always. Maybe you could try a steel screen door mesh and cut it with a box cutter along the ribs of the umbrella so it can fold nice and easy. Might try it myself now that you have sparked my brain with this video.
aluminum screen is cheaper, lighter, and easier to cut :) Actually, I don't even think you can get steel screen mesh - at least not for windows - it would rust the first time it rained.
It makes sense that the space blanket would work. Metallic paint has metal, usually aluminum. To keep the particles suspended in the liquid binder, they must be very small. So what you end up with is a lot of tiny individual metal particles, and quite a bit of empty space in between. And because aluminum exposed to air for any amount of time forms an oxide shell, those tiny aluminum particles that do touch each other can't make a good electrical connection that's needed to make an effective reflector. In contrast, space blankets use metal that's vapor deposited onto the mylar substrate at high temperature. That forms a continuous sheet of aluminum, and before it can cool and oxidize, it forms a continuous lattice. Much better electrically.
Neat, that text data at 8:21 is instantly recognizable as METAR data from Airports. From all over the country too; KBBD Brady TX, KBDU Bolder CO, and KBGE Decatur Georgia to point out a few.
Thanks for your vids. Perfect level of interesting technology without getting too deep in the weeds. Enough that gets my brain ticking and encourages me to research .
The SDR radio is £54 GBP (over $70) here in the UK, but I am going to get one next payday thanks to you and your easy to understand videos. Great Channel-
Neat! I've wanted to make or invest in a ball mill so to be able to more cost effectively make my own conductive paints. Not only for similar antenna related projects; PCB's, flexible fabric paint for RDF clothing gear and other sensor potential, shielding, etc. repair projects.
Watched like 10 of your videos, I subscribed today because of the DiY stuff 🙃 As a robotics engineering student this is the kind of stuff that is cutting edge that I draw inspiration from for projects. 🙃
There is electrically conductive paint that was applied to a model of the Ho229 to simulate the metal parts for radar experiments. They wanted to test the stealth properties of the Horten Ho229. The only drawback of this paint is that it is very expensive as it contains silver. The idea with the rescue blanket is not bad, and the idea of converting an umbrella into a satellite dish is also not bad, so I have a multifunctional umbrella. There is also zinc spray, which is 99% zinc and electrically conductive, which would also be worth a try. I saw a RU-vid video of a Russian who built one of the largest 3D printers in the world for plastic, on which you could print individual segments to build a backpack-portable satellite dish. To have internet everywhere via Starlink on the hunt for Bigfoot.
Maybe try spray adhesive and brass flyscreen (its not too expensive and much more flexible than stainless flyscreen), would be much more conductive than the blankt. Also painting on contact adhesive thinned down with automotive thinner work much like spray adesive (better coverage for the price), also applying to the outside not the inside should fold up much better. But cool video, great to see.
This was cool. The hurried wrinkled application represents what it would really be like, in an emergency, needing to get that signal having been wrapped up in a marathon blanket after the James Bond mission _(peeling off the blanket to avoid creases and then fashioning an adhoc brolly dish like that)._ A "ParaBrolla" could be its name. There would be people finding the concept of making it ever the moreso cheap and retrofitted (upcycled) from various qualities of mylar or, instead, that much cheaper atomised aluminium spray onto plastic rather than the mylar that is pricier which has foil betwixt 2 plastic sheets. At some point, even though the glued brolly fashioning technique makes a different, the atomised aluminium versus high quality mylar would in some cases be worse but good enough to still be workable, doable, and inexpensive. Radio dishes are interesting because a carrier signal _(either by the style of digital, like FPGA versus Phase-Locked-Loop)_ help the tolerance of getting a signal done and dusted onto a rig and stored as data. My comment has no hate in it and I do no harm. I am not appalled or afraid, boasting or envying or complaining... Just saying. Psalms23: Giving thanks and praise to the Lord and peace and love. Also, I'd say Matthew6.
13:09 - Great video as always Gabe. I’ll keep an eye out for one of those emergency blanket, umbrella and spray adhesive shops while I’m out later on ;-) Kitchen foil is probably better, but whatever you use, I reckon that it’s a one-way thing in terms of being able to fold it up again.
I still think foil HVAC tape worked better and was easier to apply smoothly, but I couldn't fold up the dish again with that! I did get a decent signal with a smaller diameter umbrella using the foil tape.
Love your videos, I always check every day for a new one, I been slowly building up my collection of equipment for doing my own projects. Keep up the great work 🙂
One thing to keep in mind is that an LPDA has a hair too much gain for really deep dishes like your umbrella. The feed will only "light up" the central perhaps 40-50% of the reflector. In fact, feeding really-deep parabola is a bit of a black art. That's why you'll find sat dishes typically in the F/D range of 0.3 to 0.5.
It's not really a black art - a simple waveguide feed with an adjustable choke ring around it to adjust the angle of illumination, is pretty universally used on all large parabolic dishes
So this is totally random, but I work at a glue factory and one of the things people have trouble with is spray-on glue. It's really easy to not end up with enough adhesive, you need a thicker layer than you think you do.
how many race horses with broken legs does it take to make 1 small bottle of white school paste?? How many horses does it take to make glue stick?? I bet horses hate the start of school season
The problem with Mylar, is it is a real metal surface. But it’s as close to a single atom thin as possible. Satellites use Mylar as faraday protection, but it’s a special gold Mylar. Also with shorter wavelengths, every wrinkle starts to matter. I think a far more difficult, but far more effective solution would be to cut off the fabric, and use it as a template to sew together a new cover out of Faraday fabric, or an ultra fine metal mesh if you can find it. Also cut a true parabolic curve out of cardboard to bend the frame into a more accurate shape while it’s off.
The question is, would a standard yagi antenna be just as or more effective? Yagi antenna are simple to build also but are technically horizontally or vertically polarized so perhaps the parabolic collector is better.
@@mrbyamile6973 I haven’t looked into dishes much. But it’s probably significantly more effective than a Yagi alone. Otherwise satellite command stations would just be using Yagis by themselves. I think the antenna still uses a Yagi because it has great rear and side nullification.
What you said at the end is exactly why i appreciate this channel so much, that and just your honesty and genuine enthusiasm. I must admit that i don’t understand half of what your doing when it comes to all the software but it’s the professionally winging it that’s really inspiring to see. Case and point of when you know the rules your can bend them. (Not in a legal way but as in if you know how stuff works you can do stuff with it like you do.)
Great video! I am fascinated by this, and I plan on trying myself. I wonder if automotive headliner adhesive would be a good choice? I'm in Virginia and have seen GOES16 shoot through my telescope view quite often, then I look by eye. I enjoy watching satellites disappear into darkness when they cross the day terminator. I followed Tiangong One for about a year until it fell to Earth. It's a good thing we are not neighbors! Your ingenuity is truly inspiring, thank you.
Made me happy to see how well that worked. I have seen some 3d printer fume tent boxes on linustechtips that had a flexible yet very metallic looking interior. They seemed tough. Makes me wonder if that stuff could replace the cloth of a regular umbrella.
Get two of your pcb antenna's and one of those cheap network analyzers and measure transparency by looking at signal with and with out the test sample. The reflection ignoring losses then is R=1-T. So if tran is 25% then the R is 75% more or less. I would use copper tape for a reflector. maybe alu foil.
@@saveitforparts Cu is a better conductor. You can also get Cu with conductive adhesive. That's probably not necessary. In fact Al is probably fine. :)
I would have glued smaller sections to keep it smooth, sort of like a disco ball and with a substrate so the mylar panels would be easier to apply. At least have serrated the parts of the flexible webbing so it can bend without tearing the delicate mylar. Anyways, this is all fascinating and has my brain going. It's unfortunate the practical implications are so slim.
You should have cut the blanket to each individual panel of the umbrella. Also, if a spray can is empty, remove the spray nozzle and jam the end of an air compressor on the actual nozzle of the spray can. Like refueling a torch.
If you get a tire air stem (the tapered rubber part) and keep the air valve in it, it presses down on the nozzle, but stops the air blowing back out. The air stem base fits in the circle on the top of the can. Give it a shot. They can be bought at any local tire reseller for between 3 and 5 bucks. Just make sure it has the valve in the stem.
If he had two of these umbrellas that were exactly alike and he didn't mind sacrificing one, he could carefully use a seam ripper and take it apart... and use the pieces of cloth as a pattern to cut mylar exactly to shape. These are a fairly complex shape that is not triangular (called a "gore") that you will see on hot air balloons. It's more complex by the fact that it is not on a perfectly parabolic curve.
Autoparts store sell copper gasket stuff in an aerosol can. Stinks, but I wonder if it would work? It's not paint to be clear, it's used on headgaskets and such as a sealant, but it's liquified copper.
They're also flexible solar panels and there have been attempts to make solar panel umbrellas in the past, including myself, I'm sure patents have expired by now.
You can make a simpler antenna drive by manually rotating the antenna to the azimuth of max elevation, pitch an antenna axis to the maximum elevation, then you just need a motor to pivot the antenna on the axis.
Yeah, foldable mylar antennas/reflectors has been a thing in space for years. I have also seen one taping a mylar blanket over a bucket and then draw a slight vacum in the bucket to get a parabolic shape. It might be easyer to tape a mylarsheet to a ring and make a lid from something that does not block the signal and pump it to the correct parabola. Also you should have aimed for the best signal and then tryed to manually move the antenna to find the focalpoint, that's where the gain is...
I did move the feed around to try and find the focal point, and it seemed best right about where the math said it would be. Still seems weird to me, but it is a pretty flat umbrella.
I don't think the color silver is as important as the conductivity. Maybe some copper bottom boat hull paint or some other conductive paint may work better?
In this dented antenna, the signal will arrive at the end point with a different phase components, which will demonstrate an extremely low gain. The parabaloid must be rigid and the geometry must be respected.
Looking at actual photography reflectors, I think it's worth trying to get your hands on one of these. All the ones I'm seeing have many more ribs so they're a closer approximation of a circle, and do not have the kink half way along the ribs, so they overall do actually try to approximate a parabola; where this one is just sort of vaguely similar to a parabola. Also seeing ones that are much deeper parabolas if that matters, you mentioned this being really shallow. The approximate parabolic nature of the reflector is important in photography because the goal is to create a light source that is coming in fairly parallel from a large area, it casts different shadows, more daylight-like shadows. They also look far more metallic, nearly to the point of having a reflected image (and they're huge, silly huge, 7'+). They are expensive is the thing. Maybe someone in the area can lend you one for a video. Unless you think you'd use one for your video, or for shop lighting, I don't think it makes sense to spend this much on one video.
In Europe There Is This Copper Paint For 5 Euros A Can, I Spray Painted My DoorHandles Because My Door Handles Are Pure Copper And I Accented The Sided And Stuff, Yestarday I Cleaned My Doorhandles And Git TThe Acid Acidently On The Paint And It Got Shiny, Went To Grab My tester And It Beeped On Contioniuity When IW as Around 1 Cm Away With My Pointers So That Paint Is Actually With Copper Metal Inside, I Can Send You Few Cans If You Want :)
what if u put the blanket on the other side of the umbrella the fabric should be radio transparent so it shouldnt matter if u cant see the shiny bit, that way you wouldnt need to cut it up and maybe get a more contiguous reflector surface
The other thing you could try is aluminum window screen. But see, I told you space blanket would work! You can see my original comment in the video at 0:21.
How about an emergency ('space') blanket over a circular form that you pull a vacuum on? It would be shallow, so the focus would be pretty far out there.
Gold leaf? Vapor deposition? You think you could electroplate the inside of that umbrella? I really like the idea of a lightweight, portable, durable parabolic, but durability seems like the kicker. I was really hoping the paint would work.
ONe idea I had is to use some purpose built conductive fabrica and just replace the fabric of the umbrella, I am just stuck at finding a metallic woven fabric here in europe...
