quite a few things come into play. FM stations are basically LOS (line of sight) frequencies, this means that the radio waves will not propagate off the ionosphere. The frequency wavelength is too small to be reflected back to earth so they punch through out into space. The curvature of the earth plays a big factor in how far you can get a FM signal. If the transmitting station is lower in altitude than where the receiver is then the signal will go further. At times due to atmospheric changes you can get a AM radio signal to bounce so you might pick up a signal from Boston up in Alaska but that is not normal.
so people could communicate over long distances
Vor is an abbreviated form of VHF Omni-directional Range and is a kind of radio navigation system for aircraft that emanates two types of signals - one directional and the other a 360 degree radial omni-directional. The Phase comparison gives what radial you are on by the position of the needle while DME determines the distance based on timing. It kind of works like a GPS.
One advantage of Radio over Television in this day and age is accessibility. Television broadcast has been limited to digital signals with a more limited broadcast range. Radio is still analog with a much larger, generally, broadcast range. Radio also tends to be less distracting to drivers...
In the USA, the FM stations are licensed to operate on frequencies between 88 MHz and 108 MHz. That's where they all are on the dial. If you want to listen to FM radio, that's the whole range that you need. If you want to receive other things on radio, like foreign broadcast, ham operators, time and frequency standards, aircraft communications, GPS, cellphone signals, Bluetooth signals, WiFi signals, satellite radio, garage door openers, satellite TV, fire trucks, taxis, police, or truckers on CB, then you need a radio that covers different numbers.
There are two kinds of telemetry--one-way, where the remote device sends instrumentation signals to the receiving station; and two-way, where the receiving station can send control signals back to the remote device. The range is literally unlimited--deep-space probes have two-way telemetry gear on them, and it can take months or even years to transmit a message from the vehicle to the earth.
Strengths: No wires, No Los required, greater range possible. Weaknesses: Signals become weaker over distance. Wireless signals can be intercepted so security is an issue.
satellite
Wireless Transmission Technology makes Radio devices tune to specific frequency and play the audio being transmitted from Broadcasting Radio Station.Broadcasting Radio Stationbroadcasts audio signals (from Recording Studio)asradio waves to Radio devices within Radiowave signals range.
so people could communicate over long distances
Atmospheric bounce is a technique used by Amateur Radio operators - to increase the distance their signals travel. Some frequency bands in use by amateur radio enthusiasts have a limit on the amount of power their equipment can produce. This often restricts the distance their signals can travel (sometimes to just a few miles). By using atmospheric bounce, an operator can 'reflect' the radio signal off the upper atmosphere (like shining a torch on a mirror) and thus the range can be (often dramatically) increased.
Ionosphere can enhance long-distance communication by reflecting radio waves back to Earth, which extends the range of radio transmissions. This can be particularly useful for military, aviation, and emergency communication systems that require reliable long-range communication. Ionosphere can also support satellite communication by enabling signals to travel longer distances without losing strength or clarity.
It is what radio waves bounce off of.
The range of AM radio is greater than that of FM radio because AM signals can travel long distances by bouncing off the Earth's upper atmosphere, a phenomenon known as ionospheric reflection. FM signals, on the other hand, travel in a straight line and are more susceptible to obstacles like buildings and hills, limiting their range.
Vor is an abbreviated form of VHF Omni-directional Range and is a kind of radio navigation system for aircraft that emanates two types of signals - one directional and the other a 360 degree radial omni-directional. The Phase comparison gives what radial you are on by the position of the needle while DME determines the distance based on timing. It kind of works like a GPS.
Cellphones use radio waves for transmission and reception of signals. These waves are a type of electromagnetic radiation that falls within the radio frequency range.
One advantage of Radio over Television in this day and age is accessibility. Television broadcast has been limited to digital signals with a more limited broadcast range. Radio is still analog with a much larger, generally, broadcast range. Radio also tends to be less distracting to drivers...
Earth has been broadcasting radio signals into outer space since the early 20th century, when radio technology became widely used. This means that for over 100 years, various radio signals, including TV broadcasts, have been traveling into space at the speed of light.