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No reason you can't give your dinged, battered, and abused panels a "new lease on life" by rolling them flat. I did a patent drawing a long time ago for a machine that made expanded metal. It pierced, stretched, and the last operation was to flatten and straighten with several pairs of...

Not compound curves. A parabolic dish is compound by nature in that it curves in two directions---"bowl shaped" in one direction and parabolic in the other. An "English Wheel" is the metalworking tool used for compound curves. It takes years of practice and lots of wasted sheetmetal to become...

Some form of terrestrial interferrence, like radar or phone link. Had a similar problem with my in-laws TVRO system back in the 1980's. Wound up building a 10'x10' aluminum window screen wire shield on a PVC pipe frame between their dish and the source, which was a terrestrial microwave...

Formulas that I used called for my sub (virtual) reflector to be 6" O.D. with a .4375" rise in the center. I didn't even try to plot the profile as a hyperbola, I just fabricated it from a piece of .015" aluminum sheetmetal laid out (developed) using an exercise in an old drafting textbook...

Information in picture caption may be bogus. I doubt the manufacturer would have spun a spherical reflector because the efficiency of the dish would have been reduced to that of a six foot parabolic. Microwave signals reflected near the periphery of a spherical reflector arrive at the focal...

Long ones can sub for short ones if you don't relocate the attachment points. Relocating the attachment point further towards the edge of the dish gives more mechanical advantage to move heaver dishes or give more counts between sats on smaller dishes. They all use similar components the...

I think, what you have shown frozen in time with the scope, are the points making and breaking. A small cap across the leads would clean it up, but it's not really needed. My experience with the air gap between wheel and pickup is to minimize it with only enough gap to clear any wobble of...

The real selling point for a Birdview was that it could be successfully operated by someone who had absolutely zero electronic knowledge. Most people back then had to have "experimenter's blood" in their veins to try an install of a TVRO system. My in-laws bought two systems (their sister...

B.J.: I don''t want to hijack this post by concentrating on the shape of a reflective surface, but I can't let the things you're saying go by without comment. How'd you get so confused on this subject? There's never been, and never will be, a "dish" antenna manufactured with an elliptical...

Not true. The reflecting surface is parabolic in shape. All parallel waves (electromagnetic, light, or sound) striking it's surface are reflected to one point, travel the same distance, and arrive in phase with eachother at one focal point. An elliptical surface has two focal points...

Use a No.2 wood pencil as a go-no go guage to test the reflecting surface. The rule-of-thumb for a Ku capable mesh/expanded metal/perforated dish is: If a No.2 pencil (wood part) will pass thru any opening, it's not suitable. Any surface material that the pencil WILL NOT pass thru, is seen as...

Focal length calculations assume a reflector that's true parabolic. It's possible that when the dish is assembled and you find the "sweet spot", you my find that the calculated focal point in not correct. Use the calculation as a starting point only, always adjust it in, out, and sideways to...

My definition of user friendly would have been the "petalized" four-piece-bolt-togethers with the reflective surface installed at the factory. Some were shipped in "pieces" and were site assembled, including installing individual portions of the reflective surface. Harold

Great pictures, thanks. A few questions: (1). Is it round (same dimensions north/south and east/west)? (2). What's the depth? Like you're measuring the depth of a parabolic dish with a straightedge across the top and measuring 90 degrees down to the center. Thanks again, Harold

Hey Phlat: I'm really enjoying this thread, keep those reports coming. When you get time, could you make us a detailed sketch of the scalar with dimensions? I'd like to fabricate one from sheetmetal. Thanks, Harold

The 50% efficiency figure was a nominal figure chosen by Engineers in the industry before the Chinese and Koreans took over the market. Today, most manufacturers claim 75% efficiency. Lots of factors go into the overall gain (or efficiency) that the dish provides. Materials of construction...

Wave length has nothing to do with it because the parabolic curve acts as a mirror, just a reflecting surface. The antenna located at the focal point is resonate to a specific band of the reflected frequencies.

I beg to differ with your opinion, which is not founded by science or engineering, but a parabolic surface is not frequency dependant. It does not know if it's reflecting mircowaves, lightwaves, or soundwaves.....It just reflects what hits it. In its geometry, any "wave" (electromagnetic...

Until the surface is dulled or painted the focal point is visible at night or in a darkened room by shining a floodlight boresighted on the dish. A mold machined with CNC machinery with a plus or minus 0.001" accuracy only produces an FRP or stamped metal dish rated as 50% efficient by most...

Judging from the photos, the reflective surface is not a true parabolic. Instead of the focal point being the size of a tennis ball, it's the size of a beach ball and can't get into the feedhorn. Much of the reflective surface is not being used because the microwaves are being reflected...

Check Ken Rieli's solar dish here: Solar Reflector Dish Mold by Ken Rieli Use the forward and back arrows to see the whole project. Doesn't look like he ever made the last posts to discuss the finished project. Lots of trouble to make only one dish that's probably no more than 15%...

That's the easy part because all the angles are adjustable. The hard part is maintaining plus or minus 0.015" accuracy for the parabolic curve. Without accuracy it takes a fifteen foot dish to perform like a six foot. That's the Birdview secret to performance, maintaining a true parabolic...

You could weld everything not tied down in the neighborhood to the thing and still not fix the problem. You haven't supplied enough information to diagnose the problem. Where is it flexing? If it's the post, what size is it? What's it made from? How deep is it in the ground? Is it set in...

Hold on Grasshopper.......the warning to "not touch" relates to static discharge from your body to the microwave circuitry, not for transfer of body fluids or oils. Just be sure you've touched something metal like the F fitting on the coax, to ground yourself, before putting your fingers inside...