How You Upgrade a UHF TV antenna.

Background

I was not satisfied with the UHF TV antenna that I made previously so I decided an upgrade was in order. The friend for which I made this was happy with it but it did not completely solve the poor signal issue. She ended up putting the antenna outside for better reception. Between this new antenna and the new location, the signal quality was improved but not significantly better than the Wingard unit that I had lent her previously.

1. Take the UHF TV antenna created previously. You might have noticed that the original antenna was just long enough to add another equivalent antenna below the first on the same piece of wood. This was a little bit of planning ahead and a little bit of luck.
   Prepare more pipe hangers exactly as done in the previous story.

   

   Drill 4 more holes per side with the same 5 3/4 inch spacing.

   Complete the bottom antenna exactly the same as was done in the previous story for the top antenna except for the impedance matching transformer for the bottom section. More about the transformer below. At this point, you still have a complete antenna on the top section and a mostly complete antenna on the bottom that is just missing a transformer.

From this point I tried 2 different connection methods:

Method 1 - This method uses a single transformer with an extension of the connection method used for the top antenna.

1. Undo the impedance matching transformer connections at points 3 and 8 from the original antenna. You can remove the screws and nuts to use elsewhere.
   
   Drill holes in between the top and bottom sections in much the same way that points 3 and 8 are between the 2 halves of the top antenna. See the 2 screws in the center of the picture below.

   

   Run a wire from point 5 of the original top antenna to point 1b of the bottom antenna. Strip a portion of the wire to make the transformer connection at the halfway point between the 2 points. Move the transformer disconnected earlier to the new center connection in the picture above. Purely for cosmetic reasons, I moved the tranformer to the back side of the antenna. Connect one side of the transformer to the point between points 5 from the top antenna and point 1b from the bottom.

   Run a wire from point 10 of the original top antenna to point 6b of the bottom antenna. Strip a portion of the wire to make the transformer connection at the halfway point between the 2 points. Connect the remaining side of the tranformer to the point between points 10 from the top antenna and point 6b from the bottom.

   Connect the coax cable to the tranformer and connect the other end to the TV.

Method 2 - This method uses two transformers and a splitter.

1. Add a second tranformer between points 3b and 8b exactly as added between points 3 and 8 of the original antenna.
2. Connect a coax cable between one of the 2 tranformers and the splitter/combiner. My splitter/combiner has 2 ports marked out and one marked in. I connected each of the coax cables from the 2 transformers to each of the out ports.
3. Connect another coax cable between the other transformer and the other out port of the splitter/combiner.
4. Connect the in port of the splitter/combiner to the TV.

Test Results

Both methods showed a slight improvement over the original but not as significant an improvement as I hoped for. For both methods, the number of channels received was the same as the original but the quality of the stations was slightly better although this judgement is a little subjective. I did not see a difference between the 2 methods though.

Conclusions

Even after this upgrade which show marginal improvement, I am still not happy with the antenna. I will look at making some modifications to the antenna itself and will probably add an amplifier. If anybody has any suggestions, I would love to hear them.

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