About Us › Forums › temp › Height Needed for MW Signals to Clear Path Obstructions › I probably didn’t explain
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I probably didn’t explain myself clearly, so here goes.
I had a Talking Sign transmitter installed on the ceiling of a house I owned in Pitt Meadows. I drilled a hole in the house wall through which I threaded the wire antenna. I ran the antenna up a section of PVC pipe, and mounted that pipe on the outer part of my house, so that the wire antenna remained vertical.
The first install had the wire antenna below the roofline. Range was not all that great.
I then installed the PVC pipe higher (I also moved it closer to the house so that I could use that extra wire for height) so that the antenna went above the roofline, and range improved dramatically.
For the raised antenna, I achieved the greatest range by far in the direction where there were few obstructions – it was mainly open fields. I achieved the poorest range in the built-up directions, where there were many buildings.
I concluded from this evidence that the higher the antenna, the better, primarily due to fewer obstructions.
In both scenarios, the only thing that changed was the height of the wire antenna. The ground, the transmitter, etc. remained constant.
It is true that more of the wire antenna was vertical in the 2nd scenario, but I only had to raise the pipe a foot or so, so the change there wasn’t dramatic.
It is possible that noise played a factor in the different ranges for different directions, but that cannot be said for the dramatic increase in range just by merely clearing the roofline for the antenna.
Going back to the original post, I believe that my experience at least casts some doubt that the only reason an elevated antenna may have better range is because something else is radiating, such as long audio lines, and taking the installation out of the Part 15 rules.