Bow Tie Antenna
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Transcript of Bow Tie Antenna
PROPOSAL NO.1: Bow Tie Antenna
The Bow Tie Antenna is a simple design that can be found in many variations on the web. It can be made with a 2x4, some coat hangers, aluminum foil and a few other common parts. While very inexpensive to build, this design is able to pull in stations from 45 and 50 miles away.
PROPOSED BOW TIE ANTENNA DESIGN Many combinations of antenna elements and reflectors can work well for many different reception situations which works best in these 3 sizes for TV channels 7 - 52.In a 4 or 8 bay antenna the9 1/2" whisker bowtie with 9" bay spacingworks better in the mid VHF-HI channels and UHF channels and is a good overall general purpose choice.In a 4 or 8 bay antenna the larger10" whisker bowtie with 9 1/2" bay spacingworks better in the lower VHF-HI channels and lower-mid UHF channels.In a 4 or 8 bay antenna the smaller9" whisker bowtie with 8 1/2" bay spacingworks best in the upper VHF-HI channels and mid to upper UHF channels.
9 1/2" whisker bowtie with 9" bay spacing
WHISKER DETAILS
PHASE LINE DETAILS9 1/2" x 9" phase line long X
9 1/2" x 9" phase line short twist
9" whisker bowtie with 8 1/2" bay spacingWHISKER DETAILS
PHASE LINE DETAILS9" x 8 1/2" phase line long X
9" x 8 1/2" phase line short twist
10" whisker bowtie with 9 1/2" bay spacingWHISKER DETAILS
PHASE LINE DETAILS
10" x 9 1/2" phase line long X
10" x 9 1/2" phase line short twist
REFLECTORThereflectorcan be a very important part of the antenna and can be tailored to get different results for certain situations. About anything metal will make a reflector in general larger diameter tubing or strips of flat stock can be spaced further apart and still achieve good rear rejection as compared to wire. Even good old aluminum / Tin foil strips running horizontally on a piece of cardboard will do the trick.The key to a good reflector is the spacing between the horizontal running elements within the reflector and to make it the right width for the desired channels.Angled Reflector
Curved Reflector
4 Bay Assembly Instructions
Step 1Contents should include(1) paper template(4) round PVC stand-offs(1) feed point stand-off(10) 8-32 x 3/8" screws(10) 8-32 lock washers
Step 2
Attach the paper template in position on your choice of mounting surface (back bone), make sure the template is straight and tight. Use the line to help center the template on the mounting surface (back bone), some tape on each end should secure it into position. The mounting points are marked on the template with a +, the feed point is the center mark.Mark or drill the 5 mounting points on your back bone and remove the templateSee Figure 1for details
Step 3
When attaching the stand-offs leave the screws slightly loose during this step.Attach the feed point stand-off in the center first then attach the (4) round PVC stand-offs in the remaining spots.See Figure 2for details
Step 4Find the whisker assemblies labeled 1 and 2, these should be attached to the left hand side of the antenna with 1 in the upper left and 2 in the lower right.Using the 8-32 x 3/8" screws and lock washers attach the assemblies as shown inFigure 3, only lightly tighten the screws at this time.Leave the feed point screws off at this time
Step 5Find the whisker assemblies labeled 3 and 4, these should be attached to the right hand side of the antenna with 3 in the upper right and 4 in the lower right.Using the 8-32 x 3/8" screws and lock washers attach the assemblies as shown inFigure 4, only lightly tighten the screws at this time.The feed point screws can be installed loosely at this time to make sure everything is aligned.During shipping the bow in the crossover phase lines may get tweaked, in order for everything to line up they may have to be readjusted. If alignment is still a problem recheck your back bone mounting holes with the templateStep 6Tighten all the screws except the feed point screws, the feed point screws can be tightened when your balun or feeder wire is attached.
PROPOSE OUTPUT We assume to have an output antenna of either of the following:1. 3/4 PVC using the notched stand-offs without the reflector
2. Mounted to a piece of wood using the flat back stand-offs
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