First I was thinking about using copper pipe to to the horizontal guides, but I decided to use the 2cm PVC Pipe instead. So as you can see, the drilling templates were only used for positioning. I bought 2m of it as well and it were enough. So the default parameters were very good for me, and I printed the drilling guides for my tubes.
To be honest I didnt liked much how the layout of the calculator is I think it is very confusing but it gets the right values and can even generate drilling templates.īut later I will make my own calculator and drilling generator for that. So for building a antenna, I first start searching some previous experiences with QFH in the internet. So we need a antenna that can receive circular polarized signals. This creates a need for a good omni directional antenna that can receive signals from anywhere.īut not only this: The signal is rotating a. So whenever the satellite is in range of your receiver, it will appear on one side of the horizon, and disappear on another one. Instead, they actually do one turn on earth in about 1 hour and half.
Drill a hole for the coax somewhere near the top not critical.These NOAA Weather Satellites broadcast a APT signal with about 5 to 8 Watts at 2m band, and considering how low this power is, it might suprise you that these signals arrive pretty strong at earth surface.īut the biggest challenge to receive this signals are not its power. Do not hammer the tubes, as this might compress the copper making it difficult to attach elbows. Ring terminals in these illustrations are Wire is 18 stranded. Sand the area around the holes for a good electrical connection. When satisfied, drill and tap a similar hole near one end of each of the four short top tubes. Copper is soft enough that almost any screw will do-I used screws from an old computer case. Practice drilling and tapping a hole in a scrap piece of tubing. See photos accompanying steps 5 and 6 below. Spacing between top tubes and closest bottom tube is mm. Make a template strip of wood at bottom of photo and cut copper tubes. Please refer to the referenced article for definitive information. There is nothing original in these steps. The steps below describe my implementation of Mr. Below is the link to the online calculator I used to build mine also a few pictures of the construction process. It took a friend and I about 2 hours to make it. So I used the next size up and just used a lot of solder to fill in the gaps to make the connection. I'm not going to explain have to make one, just google search for it. Making the antenna wasn't to bad, it would have been easier it I had the right parts. This time a plan on leaving it up for a while and not giving up on the first bad pass.
Now I think I have it ready, I'm just waiting to put it back up. So I have fixed that issue and have read up some more on these types of antennas. Come to find out at the top where the coax connects to each leg there was a short, didn't notice that before, don't know if that was even the issue with it the first time. Well after about year and half I got the antenna back out and studied over it again. Quadrifilar Helix Antenna (137 MHz) for NOAA Weather Satellites So I installed it on my tower at about 45ft and waited for the first flyby on a NOAA satellite, the results were not good! So I took it back down and stored it away not giving it much thought. It didn't turn out, looks wise, as well as others I had seen online but when I checked the SWR it was dead on at At the time I was very new to WX satellite reception.