Looking for a way to create quick, easy, and free RF Projection Maps? Luckily, there is a resource available that satisfies all of those needs. I have been using Radio Mobile Online since April 2015 when I was introduced to the website by my DMR friend, Don Trynor VA3XFT. The projection maps that you find on this website were created by using this website. These maps can be used to create an RF projection of the club’s repeater or for your own personal station. It doesn’t necessarily need to be used just for repeaters.
How does it work? Well, it uses mathematical formulas as well as topographic data provided by Google Maps to create the propagation maps. In my experience, the maps have been very accurate. In a town like Las Vegas, with a lot of high rise resorts and rough mountain terrain, the projections deliver the bacon. For a detailed explanation on how it all works, visit Radio Mobile Online’s about page.
Now for some pretty basic steps:
- Create an account. VE2 is the Quebec Province of Canada. French is the primary language here. Be sure to sign up in English, if you can’t read French.
- Once your account is created, click the “New Site” tab in red.
- Position the pushpin over the desired location of the transmitter. Once it is exactly where you want, it “Submit.”
- It will prompt you to name the site. I suggest you name the site by call, frequency, and street name. This is handy when you run multiple sites. (Think linked repeater systems.)
- Hit “Add to My sites.” This will save it so you don’t have to search the globe (literally) next time you want to create a projection.
- Once you have your site, hit the green “New Coverage” tab.
- Be sure to select the correct location in the “Centre Point” drop down menu.
- Enter the requested data. If you have questions on what certain things mean, check the About Me or visit Don’s website for a more detailed explanation.
- Pay special attention to the antenna heights question. You will need to convert from feet to meters. If not, your maps will be way off. I mean WAY off.
- You’ll be prompted for the specs on the transmit antenna (generally the repeater, but could be your base) as well as the receiver antenna. Keep in mind that some people are using portables which would mean the receive antenna is a rubber duck only a four feet off the ground (if on a belt) or a little bit higher if the user is actively talking/listening with portable by his/her mouth.
- Hit submit.
- It’ll take a few minutes for the computer to complete the calculations. Be patient.
- Once it’s done, you can zoom in and out using the powerful Google Maps platform.
- If you want to save the projection, be sure to hit save.
- If you want to share it on Facebook or in an e-mail, a screenshot is the way to go. If on a PC, hit the “Print Screen” button on the computer. Then paste it into paint. Crop. Add captions. Do whatever you want. If you’re on an Apple computer, hit control and F8 – then select the map. It should automatically save to your desktop.
Once you’ve read and followed these steps, you’re reading to make some plots. Visit http://www.ve2dbe.com/rmonline.html to get started. As they say in French, “Bon chance!”