Fractal Magic DIY HDTV Antenna

After reading an article about the use of fractal mathmatics in the design of cell phone antennas that have incredible bandwidth in spite of their extremely small size, I began to experiment with using a very simple fractal pattern, the Koch Snowflake, as the basis for an easy to build indoor HDTV antenna. The result of that experimentation is presented here as what I believe to be not only the best DIY HDTV antenna, but the also the simplest to build, not only in terms of the materials needed, but also in the labor required. As the holder of an Extra Class amateur radio license, I know there is no such thing as a "magic" antenna, but I started referring to this antenna as the magic antenna when I discovered that it had such amazing bandwidth, covering digital channels 2 through 60. So, with that in mind, let's get started.

Step 1: Gather The Needed Materials

Things you will need:

1 - A piece of poster board that measures 15-3/4" x 6" (400mm x 150mm). A 24" x 28"

sheet of poster board, enough to make six of these antennas, can be purchased for

about a dollar in stores selling arts and crafts supplies. This is the same material used

to make cake boxes and the gift boxes used for shirts and blouses.

2 - A pattern for making the antenna (download the pdf file).

3 - Some Scotch Tape.

4 - Scissors

5 - A map pin or other sharp pointy tool for punching holes in the poster board.

6 - 3.2 meters (10-1/2 feet) of small diameter (22 or 24 AWG) copper or aluminum wire.

A 100-foot roll of 22 or 24 AWG uninsulated copper wire can be purchased at almost

any hardware store for less than $5.00; however, there are many other sources for

copper wire, e.g. the field windings of burnt out or discarded electric motors. At the time

of this writing a package containing 30-feet of suitable aluminum wire can be purchased

at Hobby Lobby for $1.99.

7- A pair of small crimp connectors and pliers or other tool for crimping the connectors.

8 - A length of 300 Ohm Twin Lead antenna wire and a matching transformer with screw

terminals*, or...

9 - An in-line 300 Ohm to 75 Ohm matching transformer* and a length of 75 Ohm coax

cable.

Misc. - A screw driver for attaching 300 Ohm lead-in wire to the matching transformer

and a craft knife, or other knife with small sharp blade, for cutting slots A & B into the

poster board. .

*Note: I've had excellent results with eliminating the 300 Ohm Twin Lead antenna wire

and the matching transformer and attaching the center conductor and shielding of RG-6

coax directly to the separate sides of the antenna. The use of the 300 Ohm lead-in wire

and matching transformer make connecting the antenna wires to the coax cable an

easier task, but they do not seem to be required to match the impedence of the antenna

to that of the 75 Ohm transmission line.

Step 2: Download and Print Antenna Template

Print out one copy each of Part 1 and Part 2 of the antenna template. Make sure your

printer properties are set to print the images at 100% rather than “Fit To Page” or at

some reduced size. If you are not sure of your printer settings, print only Part 1 of the

template and check the side-to-side and top-to-bottom distances on the printed sheet

with a ruler before printing Part 2. Note that the measurements on the antenna

template are in millimeters, not inches. Trim the left hand edge of Part 2, lay it on top of

Part 1 being careful to align the printed pattern on both parts, and tape the pages

together to form the complete template.

Trim the excess paper from the edges of the template. At one corner of the poster

board, align two of the template edges with two edges of the poster board and tape the

template to the poster board. Cut the poster board along the edges of the template and

re-tape the template to the poster board along the edges where the tape was cut.

Step 3: Punch Holes & Cut Slots In Poster Board

Using a couple of layers of shipping carton cardboard as padding, use the map pin or other sharp pointy object to punch a hole through the poster board at each of the locations marked on the template with a dot at the points of the wire pattern. Using an X-Acto knife or other small small sharp blade, cut through the template and poster board to form slots A & B.

After punching all of the holes and cutting the slots, remove the pattern from the poster board.

Step 4: �Lace� The Wire Onto The Poster Board

Measure and cut a piece of wire that is 1.6 meters (5' 4”) in length, and starting at the hole marked “Start Here” on either side of the template, insert about ¼ inch of wire into the hole and fold it sharply so that it stays on the back side of the form. Then following the pattern on the template, alternating between front (solid lines on template) and back (dashed lines on the template) sides of the poster board, “lace” the wire around the wire pattern. Take your time doing this, being careful to not let the wire kink as you pull it through the holes. Keep the wire as tight and straight as possible between the holes. Lacing the wire from one hole through the next takes less and less time and gets easier as the amount of unlaced wire decreases. When the wire has been passed through the last hole in pattern, trim the end of it so as to leave about ½ inch sticking out the back of the poster board – one side of the lead-in wire will be connected to this end-wire. Repeat this step on the other side of the poster board. Tip: Tape down the end-wire of the first half of the antenna to the back of the poster

board so that you don't stick yourself with it while wiring the second half of the antenna.

Step 5: Connect Lead-in Wire or Coax To Antenna

There are a number of ways in which the lead-in wire, coax cable or in-line matching transformer can be attached to the antenna. The methods I have used are listed here, and as far as I can tell judging by the performance of the antenna, all of these work equally well. So, just choose the method that best matches the tools and materials you have at hand. First strip about ¼ to ½ inch (6 to 12 mm) of insulation from both wires of the 300Ω twin lead, from the braided shielding and center conductor of the coax, or from both leads of an in-line matching transformer. Then use one of the following methods to connect each side of the lead-in to the antenna. Crimp Connectors: Insert one side of the lead-in and one of the antenna end-wires into one crimp connector and crimp with a pair of pliers or crimping tool. Then repeat this procedure to connect together the other side of the lead-in and the other antenna end-wire. Soldering Iron: Twist together one side of the lead-in and one of the antenna end-wires and solder them together. Then repeat this procedure to connect together the other side of the lead-in and the other antenna end-wire.

A Pressure Connection Using Small Screws, Washers and Nuts Punch two holes near the ends of the antenna wire and insert a ¼ “ #4-32 screw with two flat washers into each of these holes and put a nut onto each screw. Insert one side of the lead-in and one of the antenna end-wires between the flat washers on one screw and tighten the screw using a small screw driver. Then repeat this procedure to connect together the other side of the lead-in and the other antenna end-wire.

Step 6: Lash Lead-in To Poster Board

Lay the lead-in flat on the poster board, and near the place where the lead-in is connected to the antenna end-wires, punch a hole large enough for a cable tie or twist tie to pass through on both sides of the lead-in. Then secure the lead-in firmly to the poster board with a small cable tie or twist tie.

Step 7: Insert Tabs A & B Into Slots A & B

Roll the poster board into a cylinder, insert Tabs A & B into Slots A & B, and fold the tabs back on the inside of the cylinder. A little Scotch brand tape on the seams works wonders in maintaining the cylindrical shape of the antenna.

Step 8: Attach Matching Transformer To Lead-in

Attach the matching transformer to the free end of the lead-in wire.

Step 9: Personalize Your Antenna

The completed antenna fits comfortably into an empty 100-count CD/DVD storage box, and this in turn can be used to display family photos, beautiful scenery cut from last year's calendar, or to display your favorite sports picture.

Almost free yet another dtv antenna.

My over the air dtv antenna. This is basically like the coat hanger antenna, but takes less space, safer if you have children around, and can be hidden behind a picture frame. I almost just poked my out with our coat hanger antenna. It was replaced with another foil dtv antenna. If you made one of those portable dtv converters, this will go perfect with it. The video I watched to make my first OTA coathanger antenna and gave me the idea for the foil antenna: http://www.metacafe.com/watch/762088/coat_hanger_hdtv_antenna_better_than_store_bought_amazing/ Coming soon: Computer controlled OTA antenna. It's mostly done, Just have not made time to finish it. http://www.instructables.com/id/Computer-controlled-OTA-TV-antenna/ - still in progress.. New antenna: http://www.instructables.com/id/Foil-based-fractal-antenna/, http://www.instructables.com/id/Yagi-foil-HDTV-antenna/

Step 1: Improvement over an existing form.

I took the plans from here (freehdtvsecrets.com), but it does seen to be in service any more) and just doubled it by hooking the ends (stubs) together and connecting the center stubs back to the hdtv converter via a transformer. I used cellophane tape instead of cardboard and paper clips to separate sections so it looks more seamless. Update: apparently the web site with original instructions is no longer available. I will update this instructable with all the details soon. For the mean time I have some quickie drawings. I think the long sections might have been 14 - 17 inches long. I will have to remeasure everything.

Step 2: Double your pleasure.

This is the old coat hanger antenna that was just a challenge to deal with and definitely not kid

friendly.

Step 3: My TV

I can not afford a fancy hdtv, but I do have my old Commodore 1702 Monitor (any analog monitor or old computer monitor with rca inputs will work fine and if your dtv converters have rca outputs).

Step 4: Final notes.

I actually made a duplicate antenna that is in parallel with the existing antenna. Works great! that is why there is no tv transformer on the cardboard page. I also recommend having the antenna on an outer inside wall of the home where there are no electrical wires to eliminate any possible loss of signal. Since setting it up, I have not had to move it. The old coat hanger antenna is no longer is use. I just had not moved it yet at the time of the picture. Though it kind of gives you a comparison in size. Good luck.

Step 5: Extra benefits

Using the antenna with Mythtv (linux based dvr aka digital video recorder and etc). I was tired so the camera might have shook a little bit. Last picture is using an old commodore via svideo with mythtv and the over the air antenna. Microsoft not required. More information about mythtv: http://www.instructables.com/id/Setting-up-a-computer-based-DVR-with-Mythtv-for-l/ http://www.mythtv.org/ http://www.mythbuntu.org/ http://www.mythtv.org/wiki/MythTV_on_Windows http://members.iinet.net.au/~davco/ http://sourceforge.net/projects/mythtvformacosx/files/

Step 6: Save the wall

Use our http://www.instructables.com/id/Paper-towel-stand/ instructable to make a

stand for the antenna.

Step 7: OTA DTV listings.

Normally the tv listings will be available for your tuner. But if you do have internet (or access to somewhere that does), you can to www.titantv.com and get more details.

Step 8: The original instructions from freehdtvsecrets.com

The original instructions from freehdtvsecrets.com less the pictures.

Aluminum Foil High Definition TV Antenna

Yes you can make an antenna from household items: aluminum foil, paper clips, string,

and tape. You will also need to buy a cable adapter from Radio Shack, Target, Walmart,

Best Buy, or anyone who sells TV accessories. If you get lucky, you can get it for 99

cents at the dollar store.

This antenna is small enough you can hide inside of every day items. For this sample it

will be hidden in a photo box. Michaels craft stores has a good price on photo boxes.

This antenna is not for outdoor use. The photo box was $3.50 and the adapter was 99

cents. A total of $4.49. Don't make me split hairs with the cost of foil, paper clips, string,

and tape. You know you already have those. That beats the $20 HD antenna I bought in

the store. The photo looks better anyway and the antenna did just as good if not better.

Read below for instructions or watch the YouTube video above or

athttp://www.youtube.com/watch?v=JccSxge3LKQ. (removed).

What you need:

Aluminum Foil Paper Clips Non-metallic Tape Scrap cardboard from a cereal box String or strap Stapler Scissors

Cable adapter 8 x 10 inch plastic or non metallic photo frame box.

Pictures: not included as the site has long been removed. Should of saved the pictures.

There are several kinds of cable adapters for sale. You need one that adapts the round

female coaxial cable stud to a flat wire with two conductors in it. Some like shown below

also have a male coaxial cable and terminals.

Since we are using a photo frame, we’ll use the inner box support as the antenna

surface.Draw a line down the middle of the box (card paper if so) lengthwise, then 2

parallel lines a half inch on both sides as shown. Draw another line across the width in

the middle.

Unroll 24 inches of aluminum foil. Cut the 24 inches of foil into six 4-inch pieces. A

single 4-inch piece is shown below.

You should have 6 pieces of foil approximately the same size. Fold each piece of foil

lengthwise in half. Repeat and repeat until you have a foil stick approximately a 1/8 to

1/4 inch wide.

Cut an 8-inch section from each of 4 foil sticks. Leave the last 2 sticks alone for now.

Fold each of the 8-inch pieces into an arrowhead with a bend of approximately 45

degrees. Tape the foil arrowheads to the surface in the middle of each of the four zones

shown. Do not tape the points of the arrowheads now; you will do that later.

Join two arrowheads with one of the last 2 foil sticks. You will use 6 to 7 inches of the

stick. Let a stub stick out and cut off the excess. Place the end of the stick on the points

of the arrowheads and carefully join them with paper clips.

Place a scrap piece of card paper (cereal box) over the straight foil stick and tape it

down.

Place the last stick over the scrap card paper and join the points of the other two

arrowheads with paper clips. You will use 6 to 7 inches of the last stick. Let a stub stick

out and cut off the excess. THE TWO STICKS MUST NOT TOUCH WHERE THEY

CROSS EACHOTHER. Be sure the scrap card paper prevents the two sticks from

touching. Tape the stick down. Now tape down the arrowhead points and the second

cross stick.

Position the cable adapter near the stubs. You will join the prongs of the flat wire to the

stubs with paper clips, but first be sure the cable adapter is positioned so the flat wires

reach the arrowhead points. If the prongs don’t separate from each other far enough,

you may need to separate the two prongs by cutting the flat wire an inch or two down

the middle between its two conductors.

Before continuing, double check that all paper clips are now taped down. Staple the flat

wire CAREFULLY between its conductors to the photo box surface so there is no stress

on the paper clip joints if the adapter gets tugged. The antenna will be ruined if the

staple touches both wire conductors. This will hold the adapter in place while you do the

next step.

Provide strain relief to the antenna. Don't rely on only the staple. You need something

beefy here. Cut a slit in the box for the strap. Strap the adapter to the box with string or

strapping. I had an extra strap and made use of it here. String will do the job too. This is

important since it will prevent movement and tugging on the antenna cable from

creating stress on the antenna.

Place a piece of card paper (cut from a file folder in this sample) between the antenna

foil and the photo. Place this stack into the photo box.

Finished. So how well did the antenna work do you ask? It worked as well as or even

better on some channels than a store bought HD antenna.

Of course you can use a larger photo box. You may want to use longer sticks and

arrows. But longer sticks and arrows may or may not work in your favor. You may want

to experiment.

Step 9: The latest antenna.

Check put the latest antenna at: http://www.instructables.com/id/Foil-based-fractal-antenna/