Intro: Gray Hoverman TV Antenna Active Element Assembly
This is how I assemble the zigzag active elements for a Gray-Hoverman tv antenna from prepared quarter-inch outside diameter copper tubing links. The links are placed on an assembly jig and soldered together. Copper elements used on indoor antennas can be attached using plastic screws. Plastic will not stand up outdoors, so elements used on outdoor antennas should be attached with metal: copper (best) or brass (commonly available) screws, washers and nuts will minimize corrosion. This is one of three Instructables that describe my method for producing consistent, quality elements that are lightweight, durable, have the desirable sharp corners and have holes for mounting the elements to the antenna's framework. To see the other two, one how to build the needed assembly jig, one detailing preparation of the links, and my other related Instructables, click on unclesam in the INFO box to the right, then repeatedly click NEXT to page through them all. To receive automatic notice when I post future Instuctables about my method for assembling the entire outdoor antenna, members can click to subscribe in the INFO box.
Step 1: Tools and Materials
Gray Hoverman TV Antenna Active Element Assembly Jig (homemade, subject of another Instructable)
8 Gray Hoverman TV Antenna Active Element Copper Links (homemade, subject of another Instructable. Those made from thickwall tubing will yield a zigzag weighing about 153 grams [5.3 oz], from thinwall tubing 113 grams [4 oz])
Steel wool for cleaning copper
Electric soldering iron or gun, heavy duty
Miniature gas torch, Bernzomatic (optional, but you know you want one)
9 number 6 flat washers
9 6-32 hex nuts (optional, for clamping the joints together while soldering, if you have the miniature torch. Now you have an excuse to go buy one)
Solder suitable for copper, plumbing or electrical type
Soldering paste (flux), plumbing, such as Nokorode
Brush for applying soldering paste
Solder flux remover, commercial (or a 50-50 mixture of mineral spirits [aka paint thinner] and rubbing alcohol--observe all safety precautions for the two chemicals)
Stiff brush for cleaning off flux
Paper towels for mopping flux remover from soldered joints
Screwdriver, small, for 6-32 screw head
Wrench for 6-32 nut
Step 2: The Assembly Jig
The prepared links are placed on the jig with their label tabs showing their proper orientations. The color pdf drawing I used to determine the dimensions of the antanna's active element many be found at this link http://www.user.dccnet.com/jonleblanc/Canada_TV_Stations/Gray-Hoverman/DBGH_VHF_hi_Antenna.pdf. The U and L letters indicate which link's flattened end pad is the upper or lower one on each screw peg. The labels and tabs help keep track of which face of which flattened pads need to be cleaned and tinned, and that those faces will be touching each other during final soldering. The links rest on nuts jammed in place on screw pegs, which allows access for soldering the joints together.
Step 3: The Prepared Copper Links
The links are cut from quarter-inch outside diameter copper tubing, either thinwall or thickwall. The links are not interchangeable, even with those of the same nominal length, and their orientation end-to-end and in rotation must be correct. Once the holes are drilled and deburred, lettered tape tabs are added to each link.
Step 4: Clean and Tin Some Link Pad Faces
1. With the links assembled onto the jig in their correct locations and orientations, note which faces of each link will need to be cleaned and tinned. Only those that will be together during final soldering should be cleaned and tinned. The small pads on links A and H need not be cleaned or tinned.
2. Use steel wool to clean the pad faces that will be tinned. It is easiest to keep track if each link is removed from the jig in turn then put back until all have been cleaned.
3. Wipe the thinnest possible smear of soldering paste onto each cleaned pad face.
4. Use soldering iron or gun and solder to put the thinnest possible coat of solder onto each cleaned pad face. Do not tin the pad faces that will not be together during final soldering.
Step 5: Check and Adjust the Pads
1. Tighten each pad in a vise to make sure it is flat and that it lies in a plane parallel to the long axis of the link. If not, press the link close to the vise jaws to stand it up straight, front-to-back.
2. With the second pad of a link chucked in the vise, check by eye to see if the other pad aligns rotationally with the one in the vise (with the jaws of the vise). If not, grip the pad with pliers and gently rotate it into alignment.
Step 6: Solder the Links Together
1. Add a number six washer on top of the top nut on each screw post. This will facilitate removal of the soldered element from the jig.
2. Place the links onto the jig in their correct orientations and with the tinned pad faces together. The tape tabs can be removed at this time or left in place.
3. If you have a miniature torch, snug a 5-32 nut onto each screw post to hold the joints together. A soldering iron or gun probably will not supply enough heat to allow use of the clamping nuts.
4. Heat each joint in turn, playing the heat over the ends of both links, being careful not to overheat the screw post or scorch the jig board.
5. Add solder at the crack between the pads and only when the joint has gotten hot enough to draw it in. Add no more solder than necessary to fill between the two pads.
Step 7: Remove the Element From the Jig
1. Allow the soldered joints to cool.
2. Remove the clamping hex nuts and lift at each joint in turn to see which ones will come off freely. Do not force. Solder will not bond to the screw posts and the washers, but the flux might cause a joint to stick.
3. For those joints that are stuck, to each in turn loosen the hex nut at the screw post's base and turn the screw head in the unscrewing direction to jack the soldered joint off the end of the screw. If the jig board is chucked into a vise for this operation, put hex nuts back on the loose joints to ensure that the element does not drop off the jig and become damaged.
4. Remove all the clamping hex nuts, remove the element from the jig and pick off any stuck washers. Handle and store the element with care.
5. Tighten those screw post base hex nuts that were loosened.
Step 8: Clean Off the Flux
Carefully clean both sides of each soldered joint with flux remover and a stiff brush and wipe immediately with a paper towel. The element is ready to be attached to the framework of an antenna. For an indoor antenna, plastic screws can be used. Plastic will not stand up outdoors, so elements should be attached to outdoor antennas with metal fasteners: copper (best) or brass (more commonly available) screws, nuts and washers should be used to minimize corrosion.
Step 9: Gray-Hoverman Antenna Information Links
1. Introduction to the Gray-Hoverman antenna
2. Antenna Research and Development Forum
3. Photo of mast-mounted outdoor G-H antenna (by others, post #94)
4. License governing the use of the antenna design information