How You Build a UHF TV antenna.

Background

A friend of mine lives in the Pennsylvania mountains or more specifically, the valleys below them. She has terrible TV reception and has tried several commercial antennas to no avail. She saw a couple of YouTube videos about home-made UHF antennas and asked me to build one for her. I looked at the videos and searched for other info and picked the style that I thought had the most promise.

I wanted to make the antenna somewhat nice looking since it will sit in the living room. Therefore, I decided to use a piece of decking left over from a previous project and spray paint it black so it would blend in the living room.

My design is loosely based on the coat hanger antennas like the ones shown in the following videos:

video 1

video 2

This project uses these pipe hangers but should work equally well with coat hangers. I didn`t have any metal coat hangers on hand, so I went to the hardware superstore with an open mind. 1/2 inch pipe Copper cladded pipe hangers at 6 inches long caught my attention; they are pre-bent to almost the perfect angle. They are also nice and shiny and have a nice presentable look. Uncladded copper hangers would work as well and were a bit cheaper. I measured the hangers and they were almost perfect, just needed a little tweaking. They were 5 per package for less than $1.5 and since I only needed 8 so I bought 2 packages for less than $3 USD.

1. Take the pipe hangers or prepare your metal hangers.
   
   The pipe hangers have a bend at each of the tips that is meant to be hammered into the beams. I bent the tips a little bit with pliers to make it easy to insert them in my vice. I used the vice for the main straightening work.

   

   Measure the total length of the hanger to be 14 inches centered at the bend. Mark the ends of the hangers to be cut such that the remaining piece is 14 inches bent at the center. For the hangers that I have, I only needed to cut off about 1/16 inch. Cut the hangers at your marked location using a rotary tool, hacksaw or wire cutters.

   

   The main bend is almost perfect right out of the package but I bent them in a little bit more aiming for 2 7/8 inch separation between the end points. The exact separation is not critical; aim for just under 3 inches. Put these hangers aside for a later step.

   Cut the decking board to the desired length. I used 48 inches so it would stand tall but just below the height of the TV that I intended to hide it behind. Also, I had it in the back of my mind that I might want to add to it to make it a double size antenna (more about that later).

   

   I wanted my antenna to be free standing, so I cut notches in the bottom of the 4 foot piece as well as an 8 inch piece I would use as a cross support. Next I assembled the 2 pieces.

   

   Spray paint the boards if you wish.

   

   Draw a line 2 inches down from the top edge of the board.

   Draw another line at 5 3/4 inches down from this first line and 2 more lines with the same separation distance.

   Drill two quarter inch holes 3 inches apart centered on each of the lines you just drew.

   The pictures below show the connection sequence. There are 2 main wires which I refer to as the black and the white; the colors really do not matter but it makes it easier to illustrate the connections. There are two columns and five rows of connections. The first, second, fourth and fifth rows are equally spaced on the 5 3/4 inch lines that you drew at a previous step. The third row is for the impedance matching transformer and is spaced half way between the second and fourth rows (ie 2 7/8 inches from each end).

   The black wire starts at the top left location (point 1) of the first row of the left column and runs across to the second row of the second column (point 2). The black wire continues to point 3 where it connects with the transformer and continues to point 4 to connect to another hanger. The wire continues back across the antenna to row 5 of column 1 at point 5 where it ends.

   The white wire starts at the top right location (point 6) of the first row of the right column and runs across to the second row of the first column (point 7). The white wire continues to point 8 where it connects with the transformer and continues to point 9 to connect to another hanger. The wire continues back across the antenna to row 5 of column 2 at point 10 where it ends.

   Make the connections at each of the points described in the connection sequence. You could solder the connections if desired. I used nuts and bolts with large washers to make the connections. I drilled two sets of holes for each hanger, but in the end I only needed one hole for each.

   

   Points 3 and 8 in the connection sequence connect to the impedance matching transformer. You can mount the transformer on the front or the back; it really does not matter.

   

   Connect the coaxial cable to the impedance matching transformer.

   

   Connect the other end of the coaxial cable to your television and you are done.

Test Results

Now for some test results. Of course after building this antenna, we wanted to test it and compare it to other similar purpose antennas. Our test is somewhat crude but very practical at the same time. The ultimate acid test of an antenna is how it performs on a television. Because most televisions have an autoprogram feature that autodetects the presence of channels, we decided to let the television decide which and how many channels would be usable. This way the test is more subjective.

Here are the antennas that we tested.

How You Build It UHF TV antenna - The antenna from this article. Results 13 channels received. Most channels received had excellent rececption; but a couple were below par but viewable if one played with repositioning the antenna.

RCA Ant-1250 - This a $50 antenna purchased recently at RadioShack. Results 7 channels received unamplified and 8 channels received amplified. All channels had excellent reception.

Winegard Color Receptor - This is a rather old antenna that I stored in my attic simply because it worked well and I can be a bit of a pack rat. Results 16 channels received. Three channels were just static and not viewable at all; they must have been on the low end of the televisions reception window.

Conclusions

Based on the test results noted above, we concluded that the How You Build It UHF TV antenna performs much better than a recently purchased $50 UHF HDTV antenna and is pretty much the same as a old time antenna from 30 plus years back.

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