naomi

North American Overlay Mapping

All About Pins

The introduction of Map Pins takes overlay-mapping to a whole new level of functionality:

  • They act as a reference point to a large variety of other positional data.
  • They can be used to compare distance and bearing to other points.
  • They act as a base point from which other tools can act.
  • They are easy to add or delete.
  • Their position can be selected from a large number of pre-determined points.
  • They can be used to quickly bookmark a map and postion, for rapid map access.
  • They are easily identified by position, country, state, type, and location.

Because of their ability to act as reference points between widely diverse data, they can be used to find answers to questions accurately and rapidly. Suppose you want to know the distance from a named town to the centre of a county. To see whether a path crosses a particular point. To see whether a station is within your radio horizon. To locate the 5 nearest airports, and get a weather forecast for them all. To get the current weather radar image for an IOTA area. To see whether two radio coverage areas overlap. To get a satellite photo of the current positon of a mobile station. All these tasks, and many more, are quick and easy to accomplish using Map Pins.

Lets examine how they work in more detail. There can be up to eight Map Pins in use at any one time, identified by color. They can all be on one map, or spread throughout the entire suite of 49 maps. There are a variety of tools that work with the current positions; other tools let you quickly see which are in use at any time, and what values they have.

Map Pins can be added in two different ways: manually or position-based. To add a Map Pin manually, just click on the map. The pin will appear, and its position will be mentioned in the Message Box, on the upper tool bar. Once eight Map Pins are in use, the next one to be added will turn off the oldest one, and use that color for itself. To turn a Map Pin off, just click on it.

To add a Map Pin automatically at a pre-defined position, you need to choose what the position-type will be, and what individual value you wish to use. This is done from the Map Navigation page. See here for a full description of how to use it. In short, it lets you place Map Pins by entered position, by Grid Locator, or by quickly selecting a value from any of the 138 different lists and sub-lists provided.

Full details of how to use each Pin Tool are provided in the specific Help Pages - see the 'Pin Tools' section in the Contents list, or check the Index. As an introduction, the examples mentioned above will all be demonstrated in the sections below. Try each one for a better understanding of the Map Pin capabilities.

Find the distance from a named town to the centre of a county:
On the Map Navigation page, in the 'Select Map by Name' box, choose 'Larger Cities' > 'San Jose,CA' > 'Go'. The Northern California map will load, and San Jose will be marked by a Map Pin. Click the tiny map above to return to the Map Navigation page, then choose 'Counties' > 'California' > 'Go'. A new box of California Counties open; from that choose 'Tulare' > 'Go'. The same map is loaded again, this time with a new pin for the centre of Tulare county. There are two ways to find the distance between the two points. Click 'Tools' > 'Pin Calculate', and the Pin-Calculate page opens. The pins are shown on a small map. The first table identifies them, and the second shows the distance we are looking for: 188 miles. Click one of the pins on the small map, and we are returned to our Northern California map. Now click 'Tools' > 'Pin Distance'. The Pin-Distance tool box opens, and shows two distance paths between the pins we have added. Click on a '?' mark, and the path will be displayed, with a label in the centre showing the distance.

To see whether a path crosses a particular point:
You are operating a VHF link from San Jose to Bakerfield. Does the path cross the '937' zipcode area, where your buddy lives? To find out, go the Map Navigation page, and in the 'Select Map by Name' box, choose 'Larger Cities' > 'San Jose,CA' > 'Go'. The Northern California map will load, and San Jose will be marked by a Map Pin. Return to the Map Navigation page again, and repeat the process, this time choosing 'Bakersfield,CA'. When the map loads, click 'Tools' > 'Pin Distance'. The Pin-Distance tool box opens. Click on a '?' mark connecting the two colored spots, and the path will be displayed. Close the Pin-Distance tool box by clicking the 'X' in its top right corner, then click 'Zipcode' on the upper toolbar. You can see the path misses the 937 area.

To see whether a station is within your radio horizon:
You live in San Jose. Your transmitter has a range of 150 miles. You want to conduct a round-table qso with ARRL section managers. How many will hear you ? To find out, go to the Map Navigation page, and in the 'Select Map by Name' box, choose 'Larger Cities' > 'San Jose,CA' > 'Go'. The Northern California map will load, and San Jose will be marked by a Map Pin. Now click 'Tools' > 'Plot Lists' > choose 'User List 1' in the top box, and click 'Plot'. The Section Managers on this map will be plotted. Now click 'Tools' > 'Pin Rings', enter 150 in the Range Distance box, and click the colored spot corresponding to the pin color for San Jose. A range-ring of 150 miles is plotted, and you see that you can only reach 5 of the 8 on the map.

To locate the 5 nearest airports, and get a weather forecast for them all:
Most local weather forecasts are based on airports, as this is where the weather data is collected. To find the nearest ones, click on the map to add a pin at that point. Click 'Tools' > 'Weather' > 'Intellicast 10 day Forecast'. When the tool page opens, click the colored spot corresponding to the pin you have just placed on the map. The chart will then list the 5 nearest airports to that spot. Click the aeroplane-icon next to the entry you are interested in, and a new browser will open and connect to the weather server for your forecast.

To get the current weather radar image for an IOTA area:
Is heavy rain going to affect the IOTA dx-pedition at NA-178 ? To find out, go the Map Navigation page, and in the 'Select Map by Name' box, choose 'IOTA' > 'NA-178' > 'Go'. When the map opens, click 'Tools' > 'Weather' > 'Weather Radars'. When the tool page opens, click the colored spot corresponding to the pin you have just placed on the map. The chart will then list the 5 nearest Doppler Radar sites to that spot. Click the aeroplane-icon next to the entry you are interested in, and a new browser will open and connect to the radar image-server for your answer.

To see whether two radio coverage areas overlap:
A rover station on Black Mountain,CA has a microwave transmitter that reaches the horizon. You live in San Jose, and have a range on that band of about 150 miles. Do these coverages overlap? Could a rover drive to a point where he could talk to both of you ? To find out, add a pin for San Jose as before. Add another pin for 'Mountains' > 'Black Mtn,CA'. Click 'Tools' > 'Horizon', where we see that Black Mountain has a height of 6216 feet. Entering that value in the 'Height of Eye' box tells us that the distance to the horizon is approx 106 miles. Click 'Tools' > 'Pin Rings', enter 106 in the Range Distance box, and click the colored spot corresponding to the pin color for Black Mountain. A range-ring of that distance is plotted. Enter 150 in the Range Distance box, and click the colored spot corresponding to the pin color for San Jose. A range ring for your transmitter range is plotted: they just overlap. Click the 'Road' button to turn on the 'Roads' foreground overlay, and you'll see that I5 would be the route for the rover station to choose.

To get a satellite photo of the current positon of a mobile station:
A mobile station calls you and reports his position as 120.17W, 39.09N. He describes the area he is in, but you'd like to see for yourself. To do that, go to the Map Navigation page and enter '120.17', '39.09' in the entry areas of the 'Select Map by Position' box. Click 'Go' and the map is loaded, with a pin at that point. Click 'Tools' > 'TerraServer', and when the tool page opens, click the colored spot corresponding to the pin color for the mobile station's position. A new browser will open with a satellite image of the Lake Tahoe coast, near Homewood.