How does transmitter repeater and antenna work in giving broadcast?

How does transmitter repeater and antenna work in giving broadcast?

1) Electricity flowing into the transmitter antenna makes electrons vibrate up and down it, producing radio waves. 2) The radio waves travel through the air at the speed of light. 3) When the waves arrive at the receiver antenna, they make electrons vibrate inside it.

What are duplexers What is their significance?

A duplexer is a device that allows bi-directional communication over a single channel. In radio communications systems, it isolates the receiver from the transmitter while permitting them to share a common antenna. Most radio repeater systems include a duplexer.

What is cavity duplexer?

Cavity filters are a type of resonant filter used for either passing desired RF signals within a specified frequency range or rejecting RF signals within a range of frequencies.

How do duplexers work?

A duplexer is a three port filtering device which allows transmitters and receivers operating at different frequencies to share the same antenna. One filter provides a path between the transmitter and the antenna, the other provides a path between the antenna and the receiver.

Why would you need to use a repeater?

The function of a repeater is to provide communications between stations that can’t otherwise communicate because of terrain, equipment limitations or both. It follows that stations able to communicate without a repeater should not use one. That way, the repeater is available for stations that need it.

Is a duplexer a repeater?

Most radio repeater systems include a duplexer. Duplexers can be based on frequency (often a waveguide filter), polarization (such as an orthomode transducer), or timing (as is typical in radar).

What type of filter is a cavity filter?

What is RF diplexer?

A diplexer is a passive (RF) filter component with three ports, which enables the sharing of a common antenna between two distinct frequency bands. This technology allows transmitters operating on different frequencies to use the same antenna and each band may both transmit and/or receive.

How is a duplexer used in a repeater station?

In most cases, a duplexer is used as part of the repeater station. The duplexers at repeaters may serve several objectives: Reduce the number of antennas required due to cost or space limits. Reduce the transmission line costs or allow a better and more expensive single cable to be used instead of two.

Are there any questions about the cavity duplexer?

If you are like many hams and two-way radio professionals, you likely have more questions about duplexers then answers. More than the other parts of a modern repeater, an aura of “black magic” and many “old-wives tales” shroud the cavity duplexer.

Can a single site antenna system be built without a duplexer?

Depending on circumstances even a single site system can be built with no duplexer at all (see the “Some thoughts on Repeater Receiver-to-Transmitter Isolation” article elsewhere on the Antenna page). And to continue the used car analogy above, used duplexers can have problems just like used cars.

Do you need a duplexer for a split site radio?

I’ve also seen a 8-cavity 4-port duplexer (it was a custom order) that allowed a 144.39 MHz simplex APRS gateway radio to share one antenna with a 146 MHz range repeater. And you may not need a duplexer at all if you run a split site system at a low RF level site.