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Comment by Swizec | Hacker News Reader

Thanks, I'm glad you took our comments to heart :)

Two questions:

1. What exactly is the purpose of the cardboard tube? I'm guessing the key point is that it's non-conductive, but would the same coil work without the cardboard? (not very knowledgable about antennae I admit)

2. How the hell does that connector even work? It looks so marvelously out of place ... does this mean the wire mesh around the normal coaxial cables is just shielding and doesn't actually do anything? If so, how come you don't need shielding?

Those were the two main questions that popped to mind, obviously I don't know anything about this stuff and I could probably look it up somewhere. But maybe someone here can provide a human-to-human good enough explanation.

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Shielding is useful but not exactly required if the signal is strong enough and the cable is short enough. EX: You can use barbed wire to send 10 baseT. However, 1 gigabit has major issues without shielding.

PS: I once noticed my Sega genesis was producing a vary fuzzy picture, so I went to fiddle with the cable and noticed it was not even plugged in. At the time I really freaked out and to this day I still wish I had a picture.

I went to fiddle with the cable and noticed it was not even plugged in.

Back in college, we were watching a, umm, adult video on my roommate's VCR. The guy from the room next door walked past, and said "oh, you're watching the movie too?". It turns out that we'd mistakenly connected the VCR's RF output to the antenna, so the guy next door was watching our transmitted movie. (although his picture was poor)

The shell of coax (and what's in the space between it and the center conductor) also affects the impedance of the cable or antenna system. It's generally not that critical for a receiving antenna.

Sticking up almost any wire more than a few wavelengths long will collect a reasonable amount of a strong signal. A truly resonant antenna for the frequency you're interested is a lot better, but not that helpful for general HDTV viewing where the frequencies range all over VHF and UHF.

One of the amazing things I've learned from years of ham radio is how many unseen and unpredictable things affect radio signals. You can move your antenna twelve inches to the left and lose a signal completely, especially inside a structure. Or an airplane flying overhead can reflect enough "multipath" signal to wreck your TV viewing for 30 seconds. Of course your own body blocks a lot of signal and is capacitively coupled to the antenna system as you adjust it. So if you're playing with an HDTV antenna and are too young to remember the fun of constantly adjusting TV rabbit ears, just keep tweaking until you get a good signal.

"...too young to remember the fun of constantly adjusting TV rabbit ears..."

Too young, ha! I use rabbit ears on my HDTV (no cable, just netflix + locals is enough for me) and laugh when I go to Best Buy and see "state of the art high definition" antennas for anywhere from $20 to $100. The same laugh hits me when I go down the gold plated monster cable isle, but that's a different story.

I used to think Monster cables were a complete joke too until a musician friend pointed out that they have a lifetime warranty and very generous terms of exchange. One can essentially walk into any music store in the country and swap out the splinched cables for new ones, no questions asked.

It's an interesting pricing model, and the $20-$60 cables more than paid for themselves after a single tour. Probably not appropriate for casual use though.

Or you could go to Monoprice and order a baker's dozen for the same price or less.

You're not a big fan of packing light, are you?

What you said may be true, but their main justification for the cost is the supposed supreme quality over cheaper cables that has been disproven time and again, and some of their cables cost much much more than $60. That's not to mention their litigation practices. They are truly a horrible company.

This is like buying an expensive car for the lifetime warranty. I could buy a 300k supercar, or I could buy 20 economy cars and rent out all but 1.

Like with the cables, neither makes sense. I could just buy one cheap cable from a reputable brand and probably not need another for 30 years.

And if I do? I'll just buy another. Because they're cheap and work perfectly.

A place not to do this is with R/C helicopters. Best to buy them from Brookstone with the 1-year no-questions-asked warranty -- you WILL destroy them and you can go through your 3-6 choppers for the price of one.

That's a case where there's real immediate risk of something breaking, so paying more for the warranty is justifiable.

And I know what I'm doing next time I'm at the mall.

Nice tip. I've always wanted to get one of the R/C helicopters and was always planning on getting it from one of the aisle mall shops - but this advice is helpful.

Is he doing it right? Should the cables fail after every show? Shouldn't he just get better cables?

Chaotic environment; hookup and unhooking frequently stresses connectors; people trip over them.

1. Basically, I just wanted something I could wind a length of wire around and stick in my window. The tube did the trick. After the show, I tried a few other things, like wrapping the tube with tinfoil, but the basic wire around the tube design performed best.

2. The shielding is there to keep signal interference out, which is useful if you have a clean source to start with (ie: Cable TV or a properly designed antenna). In my case, I just wanted to pick up as much signal as possible, and this is what I had to work with.

very Interesting attempt. I would like to give a try. Btw, did u do some math in arriving at length of cable or the number of winds? Did u try increasing number of winds etc?

1. Structure. The wire he's using isn't strong enough to just stay up standing by itself. It would fold over on itself. Also, it probably does need to be non conductive or you need to use coated wire.

2. It's not shielded because the entire thing is the antenna. I guess he could shield it between the TV and the actual wrapped tube part but this is sow low-tech it wouldn't make a difference. Your standard roof mounted antenna is shielded between the antenna and the tv because you don't want interference between the two points.

>Your standard roof mounted antenna is shielded between the antenna and the tv because you don't want interference between the two points.

To clarify this, with a roof mounted antenna the wire needs shielding because it is typically running down the middle of the house and thus would be subject to interference from the many electronic devices therein.

With this guy's solution, the wire just runs out of his window, and therefore as long as he doesn't have any ageing analogue equipment (speakers, cordless phones etc) near his TV or his window the issue of interference is minimal.

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