# Is FM A Line Of Sight?

## How far can the human eye see?

Based on the curve of the Earth: Standing on a flat surface with your eyes about 5 feet off the ground, the farthest edge that you can see is about 3 miles away..

## How far will a 1 watt FM transmitter go?

If the antenna can see 20 miles, but say 1 Watt ERP of power used, it’s very likely that about 1 mile of range will result. This is quite simply because there is not enough power to propagate the signal 20 miles. If 50 Watt ERP is used, it’s very likely that 20 miles of range will be achieved.

## Why is height of VHF antenna important?

Height. In general, the higher the antenna, the better the range of your radio. VHFs transmit via “line-of-site” radio waves–therefore the higher the antenna, the farther your signal will reach over the horizon.

## Does VHF need line of sight?

It depends somewhat of what you mean by “VHF”. The frequency range of 30 to 300 MHz that is defined as VHF does not normally support any other propagation modes than ground or surface waves. These are limited to line-of-sight and sligthly beyond using “reasonable” antenna sizes and power levels.

## How does line of sight work?

It is a rather simple principle: In order to view an object, you must sight along a line at that object; and when you do light will come from that object to your eye along the line of sight. A luminous object emits light in a variety of directions; and an illuminated object reflects light in a variety of directions.

## How far will VHF transmit?

Transmission power ranges between 1 and 25 watts, giving a maximum range of up to about 60 nautical miles (111 km) between aerials mounted on tall ships and hills, and 5 nautical miles (9 km; 6 mi) between aerials mounted on small boats at sea level.

## Are cell phone signals line of sight?

Cellular signals are “line of sight”. … Cellular signals can be blocked or decreased by certain obstructions — Metal, concrete, Brick, lead and masses of earth (such as a hill or mountain) are a few.

## How do you find a line of sight?

Checking Line of Sight#Use the ruler tool to measure the distance between the two points.The ruler tool will show you the distance and the azimuth between the two points.Click ‘Save’ on the ruler tool. … Go to the ‘Altitude’ tab on the line properties.Change ‘Clamped to Ground’ to ‘Relative to Ground’More items…

## How far can FM signal travel?

40 milesReception distance VHF Radio waves usually do not travel far beyond the visual horizon, so reception distances for FM stations are typically limited to 30–40 miles (48–64 km).

## What radio frequency travels the farthest?

If you are speaking of furthest as to the radio waves being received by another station on Earth then short wave or HF, signals in the 3–30 MHz range can travel all around the Earth. The signal will bounce off the ionosphere and back to earth and continue doing this around the Earth.

## How far can a 5 watt radio transmit?

So according to our rule-of-thumb, 2 people around 6 feet tall using a 5 watt handheld two-way radio, used on flat ground with no obstacles, will have a maximum range of approximately 6 miles.

## What does clear line of sight mean?

Management of Portfolios (MoP®) introduced the concept of ‘clear line of sight’, a technique that seeks to ensure a transparent chain is continually demonstrated from strategic intent through to benefits realization.

## What does line of sight mean?

1 : a line from an observer’s eye to a distant point. 2 : the line between two points specifically : the straight path between a transmitting antenna (as for radio or television signals) and a receiving antenna when unobstructed by the horizon.

## How do you draw a line between two points on Google Earth?

Draw a path or polygonOpen Google Earth.Go to a place on the map.Above the map, click Add Path . To add a shape, click Add Polygon. … A “New Path” or “New Polygon” dialog will pop up. … To draw the line or shape you want, click a start point on the map and drag.Click an endpoint. … Click OK.

## Why line of sight is required for FM?

Therefore, since the ability to visually see a transmitting antenna (disregarding the limitations of the eye’s resolution) roughly corresponds to the ability to receive a radio signal from it, the propagation characteristic at these frequencies is called “line-of-sight”.

## What is line of sight range?

Line of sight is the direct free-space path that exists between two points. Using binoculars on a clear day, it is easy to determine if visual line of sight exists between two points that are miles apart.