I was futzing around building a uhf bowtie antenna and needed some fender washers. The hardware store is 6 miles away in a truck that gets 12 mpg when cold. Figure the 8 washers for ~3 cents each and 45 minutes wasted, and I'm about ready to drop the project .
An Edison moment... pick up the metal punch, fish 8 cents out of my pocket and instant fender washers! Cost 8 cents versus~$4, and only took about two minutes.
I needed a larger one when repairing my truck today - a nickel and electric drill...
The "penny presses" that create souvenirs from a penny certainly deface a coin, but they are legal. Even usage "defaces" a coin - you should have seen the silver half dollar I found in the back of the drum of a electric dryer when replacing all the rollers ;-)
Maybe there's a difference between hard "coinage" and paper "currency"?
But the ones you get from the store are made with steel, not zinc.
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I suspect he's trying to hold pieces of coat hanger wire so zinc vs steel won't be an issue. It may be better as pennies don't rust - or do they?
G²
There is a problem with using the copper clad zinc coins as washers. They will act as a cell in a reactive environment and disappear. BTW: Its not against the law to deface currency, you can burn all of your money if you like.
Do coins count as "currency?" I thought that "currency was only the paper. Are they going to arrest everybody who's ever put a penny on the railroad tracks? ;-)
I even saw some construction thing for some kind of EKG or EEG or EMG or something, that actually recommended using pennies for electrodes, in PopTronics some decades ago.
Well, I had some aluminum ground wire that straightened with a little effort and used that since I couldn't find spare coat hangers.
It is indoors so rust or galvanic action isn't an issue.
Here's one for an RF guru though: I made this reflector out of a wood frame and "hardware cloth" (1/2" mesh). Doesn't work at all well. Whilst experimenting I tried an unused BBQ grill as a reflector - worked pretty well as long as the wires were aligned with the bow ties (same plane, parallel wires with ~10" between them - grounded is better than floating).
The next time I was at the dollar store I picked up some "el cheapo" cake trivets (cooling racks) out of really wimpy gauge wire; they work as well as the grill top and are lots lighter.
My question ... if this is a "reflector" why won't the hardware cloth work? I haven't tried to figure out where the stations are exactly, but I'm thinking that they are probably on the reflector side, since there's an ocean to the east of me.
Defacing? -
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It is against the law to deface U.S. coins. Fact or Fiction?
Trick Question. It is somewhat fact and somewhat fiction. It is not illegal to deface coins BUT they can no longer be used anywhere for currency or you would be breaking the law. It is perfectly legal to drill a small hole in a nickel, paint a quarter, or bend a penny if you want.
According to U.S. code Title 18, Chapter 17, Section 331:
" Whoever fraudulently alters, defaces, mutilates, impairs, diminishes, falsifies, scales, or lightens any of the coins coined at the mints of the United States, or any foreign coins which are by law made current or are in actual use or circulation as money within the United States; or
Whoever fraudulently possesses, passes, utters, publishes, or sells, or attempts to pass, utter, publish, or sell, or brings into the United States, any such coin, knowing the same to be altered, defaced, mutilated, impaired, diminished, falsified, scaled, or lightened --
Shall be fined under this title or imprisoned not more than five years, or both."
I seem to remember copper pennies having a law protecting them when the value of the metal went over the metal in the penny.
I'm not sure as to what hardware cloth is, but you can run into strange behavior if the distance between two conductors in the reflector is a half or quarter wave length apart at the operating frequency. Ideally the conductors in the reflector should be 1/10th or less, of a wave length apart. The closer to approximating a solid sheet the better.
I can't swear to the date, but I do seem to recall that during some year in WWII, they made pennies out of steel because copper was needed for the war effort. I learned this about 40 years ago, when everybody was on a coin-collecting jag, and I do remember seeing some description of steel pennies.
Or, I might have dreamed it. I'd say the best route would be to check with a "real" coin person - if you have copper (or, actually bronze) pennies from
1943, they could be worth a fortune, or maybe you could get a couple of bucks for the value of the copper.
Actually what we call "chicken wire" is twisted into hexagonal patterns with all the wires going longitudinally with the length of the roll. It is galvanized before it is twisted - unless you buy the marine grade - for fish or crab traps which is hot dipped or plastic coated after it is twisted.
I got the reflector I made out of the shed. I was mistaken it is 1/4" (fine) mesh.
Same game, it doesn't work. At ~18+" it has little effect then it steadily attenuates the signal as it gets closer to the dipoles.
I tried rotating it 180 degrees putting the reflector on the other side and that is even worse.
I looked at some ads for that type antenna and they also seem to use horizontal parallel reflector wires not a cross hatch. If they have vertical wires on the reflector it is in the center and edges only - more for structural strength.
Seems to me a "reflector" is intended to reflect so wouldn't you want to observe some multiple of 1/4 wave? Ideally shouldn't the reflected signal get back to the dipoles in phase with the primary wave?
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