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http://www.instructables.com/id/Gray-Hoverman-TV-Antenna-Plastic-Crafts/ Food Living Outside Play Technology Workshop Gray Hoverman TV Antenna Plastic Crafts by unclesam on January 4, 2011 Table of Contents Gray Hoverman TV Antenna Plastic Crafts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Intro: Gray Hoverman TV Antenna Plastic Crafts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Step 1: The Sharpie Sled . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Step 2: Mark Pipe Quadrants Without a Circle Template . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Step 3: Mark CPVC Pipe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Step 4: Mark PVC Fittings For Drilling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Step 5: Mark CPVC Fittings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Step 6: Drill Pipe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Step 7: Let's Stick Together . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Step 8: Attach 1-1/4 inch Pipe to 1-inch Tee . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Step 9: Active Element and Straight NAROD Holders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Step 10: Tophat NAROD Holder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Step 11: Antenna Information Links . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Step 12: Plastic Spine for GH10n3 Antenna . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Related Instructables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Comments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
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Gray Hoverman TV Antenna Plastic Crafts

Oct 08, 2014

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Page 1: Gray Hoverman TV Antenna Plastic Crafts

http://www.instructables.com/id/Gray-Hoverman-TV-Antenna-Plastic-Crafts/

Food      Living       Outside        Play        Technology       Workshop

Gray Hoverman TV Antenna Plastic Craftsby unclesam on January 4, 2011

Table of Contents

Gray Hoverman TV Antenna Plastic Crafts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Intro:   Gray Hoverman TV Antenna Plastic Crafts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Step 1:   The Sharpie Sled . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Step 2:   Mark Pipe Quadrants Without a Circle Template . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Step 3:   Mark CPVC Pipe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Step 4:   Mark PVC Fittings For Drilling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Step 5:   Mark CPVC Fittings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Step 6:   Drill Pipe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Step 7:   Let's Stick Together . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Step 8:   Attach 1-1/4 inch Pipe to 1-inch Tee . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Step 9:   Active Element and Straight NAROD Holders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Step 10:   Tophat NAROD Holder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Step 11:   Antenna Information Links . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Step 12:   Plastic Spine for GH10n3 Antenna . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Related Instructables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Comments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Page 2: Gray Hoverman TV Antenna Plastic Crafts

http://www.instructables.com/id/Gray-Hoverman-TV-Antenna-Plastic-Crafts/

Intro:  Gray Hoverman TV Antenna Plastic CraftsThe Gray-Hoverman homebuilt TV antenna can be assembled from common plastic plumbing pipe and fittings. Here are some tips compiled from my build of a GH6antenna having straight NARODs, but these hints can be useful no matter which of the many variations you build. The color pdf drawing I used to build my antenna maybe found at this link http://www.user.dccnet.com/jonleblanc/Canada_TV_Stations/Gray-Hoverman/DBGH_VHF_hi_Antenna.pdf . Note the license information printed onthe drawing, which is offered free for private use, but commercial exploitation is prohibited.This is one of several of my Instructables related to building this antenna. To see the others and my related Instructables, click on unclesam in the INFO box at right andrepeatedly click NEXT to page through them all. To receive automatic notice about my future antenna construction postings, you can click in the INFO box to subscribe tome. In the final step I include links within Digitalhome.ca that further describe the antenna. At the end I have edited in an assembly photo of the spine for a GH10n3antenna I subsequently built.

Step 1: The Sharpie SledHoles need to be drilled in lengths of PVC pipe that are precisely placed in spacing and perpendicularily, and marking the pipes lengthwise on four quadrants makes thateasier. This is best done after a piece of pipe has been cut to length. The pipe is clamped to a flat surface in several places, so that the pipe is in contact with the surfacealong its entire length. A fine-point marker fastened to a wood block is carefully drawn along the length of the pipe. Locations of the remaining quadrants may be markedusing a circle-drawing template. The pipe is then rotated and clamped in position so the marker's point will follow each of the remaining quadrant marks in turn along thepipe's length.

Image Notes1. STEP 1 Run a line the length of the pipe.

Page 3: Gray Hoverman TV Antenna Plastic Crafts

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Image Notes1. STEP 2 Mark the remaining three quadrants.

Image Notes1. STEP 3, line the remaining quadrants.

Step 2: Mark Pipe Quadrants Without a Circle TemplateThe remaining quadrants can also be marked using a narrow strip of paper after one line has been made along a pipe using the Sharpie Sled. With one end of the stripset to the line, wrap the paper to overlap, then mark the point of overlap. This creates a strip of paper whose length is the circumference of the pipe. Fold just thecircumference in half and crease it, then fold that in half and crease it, then mark the three resultant folds. These and the original mark divide the circumference equallyinto four parts. Wrap the paper around the pipe with the original end against the line again, secure it with a rubber band, and transfer the remaining quadrant marks to thepipe. Do the same at the other end of the pipe then connect the dots using a straightedge.

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Image Notes1. STEP 1

Image Notes1. STEP 2

Image Notes1. STEP 3

Image Notes1. STEP 4

Image Notes1. STEP 5

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Step 3: Mark CPVC PipeI used some half-inch CPVC pipe in my antenna, and it needs to be marked lengthwise on opposite sides so it can be drilled and secured into the antenna with the properrotational alignment. The mold marks on two CPVC tees can be used to accurately mark lines along the pipe on opposite sides. The mold marks on the tees areenhanced with scribe or marker. The tees are placed on the ends of the pipe and their bases pushed onto a flat surface to align them in the same rotational position. Themold marks are transferred onto the pipe on opposite sides, then the dots are connected using a straightedge.

Image Notes1. STEP 4

Image Notes1. STEP 1

Image Notes1. STEP 2

Image Notes1. STEP 3

Step 4: Mark PVC Fittings For DrillingPVC fittings need to be drilled in precise locations. Their mold marks (enhanced in the photos with pencil) locate their centers in one axis, and the mold marks of twoidentical fittings can be used to find the center of a tee in the other axis. The center is punched to help start a drill, or if the hole needs to be offset from the center, theoffset is measured and that spot punched. I mark the spot on both sides of a fitting and drill both sides, rather than drill through from one side. Two tees can be clampedso that a straightedge can mark the center of the middle tee in its other axis, and the same can be done to mark the center of a cross fitting. A forstner bit is stiff and hasa sharp point, so it will start in the punch mark without wandering on the curved surface.

Image Notes1. Mold marks on two outboard tees help find center of second axis of middletee.

Page 6: Gray Hoverman TV Antenna Plastic Crafts

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Image Notes1. Drilling the holes with precision ensures that the assembled antenna'scomponents will have the proper spatial relationship.

Image Notes1. Mold marks on two outboard cross fittings help find center of second axis ofmiddle tee.

Image Notes1. Forstner bit's sharp point will find center punch mark, will not wander oncurved surface.

Step 5: Mark CPVC FittingsHalf-inch CPVC fittings can have their centerlines marked for drilling or as an aid to alignment during antenna assembly. The fittings have tapered bells, so provisionneeds to be made to keep them level for marking. A temporary arrangement of other fittings can be assembled to keep the fitting from rocking, and fittings can be addedto the outboard fittings to also keep them from rotating. The mold marks of the outboard fittings (enhanced in the photo with pencil) can be used to mark the other axis ofthe fitting in the middle. The centerline of the top of the tee can be marked in a similar way using only the two outboard tees connected by short pipes. The bottom edgesof the two bells of the two outboard tees are pressed onto a flat horizontal surface, to align the two together rotationally, and the bell of the middle tee pressed against avertical surface perpendicular to the horizontal surface. A straightedge can be used to mark a line along the top of the tee.

Page 7: Gray Hoverman TV Antenna Plastic Crafts

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Image Notes1. The face of the bell of the middle tee is rotated to press against a surfaceperpendicular to the horizontal work bench, while the faces of the bells of theoutboard tees are kept pressed to the work bench.

Image Notes1. Mold centerlines of the two outboard tees find the centerline of the top ofthe middle tee.

Step 6: Drill PipeOnce the pipe is lined along its quadrant axes, the locations of the holes to be drilled are measured and marked with a center punch, on both sides, so each of the thruholes can be drilled from both sides. Using my method for assembling the antenna, the hole locations are measured from the lengthwise middle of the pipe, then outwardtoward both ends. I use a drill press having a moveable vise. I select two hardwood or metal rods having exactly the same diameter to cradle the pipe, rather thansqueeze it with the vise. The rods allows me to make all the holes exactly on the diameter of the pipe without having to repeatedly adjust the front-to-back location of thepipe under the drill's quill. Once the quill is exactly centered between the jaws of the vise, a tube set onto the dowels can be positioned by sliding it lengthwise androtating it so the hole's punch mark meets the point of the drill bit. The vise is first centered front-to-back under the drill's quill by chucking a precision circular object in it,such as a large forstner bit. The vise is adjusted toward the user until its fixed back jaw touches the bit. The moveable jaw is then adjusted until it touches the bit. The bitis withdrawn and removed from the chuck. Neither the vise's position nor that of its moveable jaw should be moved until all the holes are drilled. With the drill turned off,the sharp point of a forstner bit is best for finding a punch mark as the pipe is slid and rotated under it. Once found, the quill is locked down and a hold-down is used tosecure the pipe. The drill is turned on, the quill is unlocked and the hole drilled. Not shown is a shop vac nozzle that is positioned to catch the chips.

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Image Notes1. Step 2, mark the locations of the holes to be drilled and make center punchmarks.

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Image Notes1. Step 2, two dowels or rods of same diameter support the pipe in the drillpress vise.

Image Notes1. Step 3, center the quill over the vise by adjusting position of vise until fixed jawmeets solid round object chucked in the drill press.

Image Notes1. Step 4 Close the vise's moveable jaw until it touches the round object.

Image Notes1. Step 5 Slide and rotate the pipe until a punch mark falls under the bit's center.

Page 10: Gray Hoverman TV Antenna Plastic Crafts

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Image Notes1. Step 6 Move a hold-down in position to keep the pipe from moving duringdrilling.

Step 7: Let's Stick TogetherPlastic pipe and fittings are assembled by first priming and then cementing them using only products sold specifically for that purpose. An all-purpose cement will work forPVC and CPVC, and the resultant joint will be as strong as if the two pieces were manufactured as one. The photo shows a test of my method for cementing a half-inchCPVC pipe through a PVC pipe. The CPVC was pushed in to almost its final position, then cement was dabbed on the CPVC using a Q-tip, only on the part outside thePVC. The CPVC pipe was rotated and pushed in about a quarter inch, then cement dabbed on the protruding short end of the CPVC, only outside the PVC, and theCPVC pipe drawn back, while being rotated, to its intended eventual location and rotational position. The joint was left alone overnight then was subjected to a straightpull test of 75 pounds for 24 hours, then gripped with pliers and twisted with all the massive upper body strength of a retired engineer. The joint showed no hint of failureor even weakening.During final assembly of the CPVC pipe parts into the PVC parts, the parts are tried dry and measurements made, then marked, or spacers used, toensure that the antenna's elements will be cemented in place with the correct spacings and rotational orientations.

Image Notes1. Reflector rod thru vertical PVC spine of antenna.

Image Notes1. Test joint CPVC primed and cemented thru PVC

Page 11: Gray Hoverman TV Antenna Plastic Crafts

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Step 8: Attach 1-1/4 inch Pipe to 1-inch TeeMy antenna attaches to a mast of 1-1/4 inch diameter, which is a snug sliding fit inside a 1-inch PVC "cross" fitting. I used 1-inch fittings and short pipe tubes for theremainder, but wanted to use 1-1/4-inch PVC pipe for the antenna's vertical spine. I found a way to join the spine directly to a 1-inch tee without need for two additionaladapters. The inside diameter of 1-1/4-inch pipe is only 30 thousandths of an inch larger than the outside diameter of 1-inch pipe. I drilled four 3/8-inch diameter holesone and one quarter inch from each end of the 1-1/4 inch pipe, then slit the pipe from the ends to meet the holes. Gentle pressure from two hose clamps is enough tosnug the pipe onto a 3-inch long section of 1-inch pipe, with a jig used to set the proper length and rotational alignment during cementing.

Image Notes1. Lengths of 1-inch pipe connect the PVC fittings together, and the jig assuresproper spacing and spatial orientation. The spine connects to a tee via a three-inch length of pipe.

Image Notes1. Gentle pressure from tightening the hose clamps will snugly tighten the 1 1/4-inch pipe onto the 1-inch short pipe that is 3 inches long.

Image Notes1. Correct spacing and rotational position are assured by using and assembly jig.Pegs of 1/2-inch CPVC are fit into holes in the jig through holes in the PVC.Those holes in the PVC will eventually receive 1/2-inch CPVC parts of theantenna.

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Step 9: Active Element and Straight NAROD HoldersI formed holders for the ends of the antenna's active elements, which I made from 1/4-inch copper tubing, and the straight #10 copper wire NARODs, using 1/2-inchCPVC pipe and modified "bracket" 90-degree elbows. These elbows were chosen because they have a square bend, and the brackets were sawed off. I first used themold seams on a different style elbow to mark the centerline on both sides of each bracket elbow for later drilling a hole to run the NAROD through. I then cemented alength of CPVC pipe into the elbow and made two saw cuts on the bandsaw. Sawing created a flat for bolting the end of my active element to, just the right distancebelow the NAROD's support hole (hole not shown).

Image Notes1. The centerline of the elbow is scribed using the mold marks on a street elbow.The hole that will pass the NAROD through will be drilled on that centerline,directly above the flat that will be cut to accept the active element flat.

Image Notes1. Two saw cuts create a flat, exactly the correct distance below the hole (holenot shown), drilled crosswise on the centerline of the elbow fitting, that will passthe NAROD through.

Image Notes1. Flats on the holders support the flats on the active elements via brass screwsand nuts, and bronze lock washers. Holes through the holders support thestraight wire NARODs. End of the NAROD ends in a pipe cap that has a holethrough only one side.

Page 13: Gray Hoverman TV Antenna Plastic Crafts

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Step 10: Tophat NAROD HolderI designed my antenna with a straight NAROD, but built in provision for trying out the several shapes and sizes of tophat NARODs. The photo shows how a 90-degreestandard elbow can be drilled through to make an adjustable holder. It can be slid up and down and back and forth, then cemented in place to accommodate any tophat.A modified pipe cap confines the tophat, simulated in the photo by a short length of copper tubing.

Image Notes1. The holder can be adjusted to meet and support a NAROD of any shape, simulated here by a short piece of copper tubing.

Step 11: Antenna Information Links1. Introduction to the Gray-Hoverman antennahttp://www.digitalhome.ca/ota/superantenna2. Antenna Research and Development Forumhttp://www.digitalhome.ca/forum/forumdisplay.php?f=186"3. Link to the license:http://www.gnu.org/licenses/gpl.txt

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Step 12: Plastic Spine for GH10n3 AntennaFollowing the SBGH6, I built a GH10n3 antenna that has high gain for VHF-high and UHF channels. The photo shows the stages of assembly for the spine. This antennaworked very well.

Page 15: Gray Hoverman TV Antenna Plastic Crafts

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Related Instructables

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Gray HovermanTV AntennaPlastic FrameAssembly byunclesam

Gray HovermanTV AntennaReflector Rodsby unclesam

GH10n3 Gray-Hoverman TVAntenna(Photos) byunclesam

Gray HovermanTV AntennaActive ElementAssembly byunclesam

NARODBending Jig forGray HovermanTV Antenna byunclesam

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Comments

3 comments Add Comment

 crc60 says:  Oct 27, 2011. 10:24 AM  REPLY"which is offered free for private use, but commercial exploitation is prohibited."

The GPL allows anyone to copy, use and re-publish the DBGH_VHF_hi_Antenna.pdf illustration be they private use or commercial exploitation. GPLprevents limitations on who can copy the file. That's the price of using GPL.

Of course, private and commercial folks are also free to use the Hoverman design (patent expired) or the Gray-Hoverman (never patented and published formore than a year). The GPL has nothing to do with this since Ideas, procedures, methods, systems, processes, concepts, principles, discoveries, or devices(as distinguished from a description, explanation, or illustration) cannot be copyrighted.

Ignore those trying to use the GPL to regulate design concepts.

 olivehelens says:  Jun 29, 2011. 7:00 PM  REPLYPVC fittings need to be drilled in precise locations. I agree with this statement. Please check idccorp.com for more information about PVC Fittings.

 dmonday says:  Jul 1, 2011. 3:08 PM  REPLYYou can check your local home improvement store like menards or home depot and save shipping charges, instead of looking for these common itemson the web.