How an Antenna Diplexer Allows for Multiple Broadcasts on One Transmitter

A diplexer, which is a form of duplexer, is a three-port frequency-dependent device used either for transmitting or receiving purposes.

It can take different frequency bands and multiplex and de-multiplex two ports and put them onto one port on a single coaxial cable. Or a diplexer can route signals based on frequency that have a sufficient wideband and able to and transfer them to the air efficiently. A diplexer essentially combines signals onto one download or perhaps link those being passed through it onto radio transmitters.

This passive device can also split two signals apart from being on the same receive path like audio and data in Digital Subscriber Line (DSL) telephone systems or combine two signals into one single output on the same transmit path. It’s also capable of forcing constant impedance to occupy a single broadcast frequency or enable one transmitter used by a broadcast station to operate and transmit multiple frequencies at the same time off one RF antenna.

In addition, an antenna diplexer is an electronic component that can also be used to transmit and receive simultaneously using the same antenna – or it can enable a single antenna to be used while preventing the output of the other or else. They allow signals such as from an antenna and a satellite TV dish to share the same feed. Even more, it can separate signals according to the frequency they use.

On the downside, diplexers are not for signals that have overlapping frequency ranges. And if transmitters have frequencies too close together they cannot be combined successfully by a diplexer.

Typically, diplexers are used for high frequency satellite signals and low frequency CATV (cable television) / OTA (over-the-air) antenna signals. They can be also be found as part of a front end module for a mobile telecommunication system.

Diplexers are essential when trying to overcome the problem of the ban on building new transmitting towers in some areas. It is very hard nowadays to get permits to build new transmitting towers in many places as there are laws that say one can no longer build towers. Federal Aviation Administration (FAA) and Federal Communications Commission (FCC) rules related to tower erection restrictions and local zoning regulations drive many of these restrictions.

Although there are exceptions for businesses categorized as “public utilities” to build even in zones where it is explicitly prohibited, in reality constructing new towers is nowadays almost impossible.

Overcoming the problem is possible only by utilizing an existing tower as much as possible. Agreement must be found with owners of established transmitting sites. This is where diplexers come in to play – by allowing two frequency bands to be transmitted together without interferences.

Diplexing is a suitable solution for medium wave broadcasting stations and to allow more than one transmitter such as UHF-/VHF from a single pre-built tower to be used for broadcast television reception.

It is said that diplexing AM (Amplitude Modulation) transmitters is easier than diplexing FM (Frequency Modulation) transmitters due to the fact that not all radiators will work for that type of transmissions. Antennas, in fact, must be broadbanded to allow the broad range of FM frequencies to be transmitted.

Distance is also a factor as it affects FM transmission more than AM ones.

Due to the special attention FM duplexing requires, costs might be a concern if the antenna was not already built for this type of transmission. Other factors that need to be evaluated include:

  • Are tower antennas are non-directional or directional?
  • What’s the antenna efficiency?
  • Does the tow have the needed orientation?

Examples of tower mounted diplexers (TMDs) are abundant.

An example of a TMD is the Sutro Tower of San Francisco, a 977-foot steel tower used by 11 television stations, four FM radio stations, as well as satellite companies, cable providers and for wireless communication services. Even more iconic is the Empire State Building in New York that hosts a very busy diplexer that appeared way back in March of 1952 where ABC and CBS FM stations operated from a common antenna.

The signals were diplexed into a single set of dipoles on the latter stations’ antenna near the bottom of the tower.

It is clear how diplexers are essential in allowing new transmissions even though there are building prohibitions against new towers. Thanks to these devices, stations are able to prevent intermodulation and keep the voltage component of a standing wave (VSWR) to the lowest amount for each input transmitter and frequency even in presence of tower building blocks.

Consequently, new transmissions can still be allowed.

Despite this, diplexers appear to meet both the wishes of residents who don’t want any more towers built and able to serve the interests of businesses needing to have transmit/receive antennas for telecommunications. With this device and purpose, towers can be used to provide the locals with communication systems capabilities and companies the ability to have a transmission medium to conduct business.

Make Yourself Into a Human Antenna

Why would you ever need to make yourself into a portable human antenna? Well how about for Police, Fire Fighters, First Responders, Field Researchers, Military and FEMA?

We propose building a uniform for infantry communication specialists, which is an antenna. The sleeves will have elongated zippers. One sleeve will have a zipper which when open will expose a nickel silver antenna, which will go from the elbow to the wrist. The other arm will have an antenna when exposed which goes from the shoulder to the wrist. The longer antenna will have a wire tube, which can be connected to the midpoint of the other forearm antenna.

This wire tube will when extended point past the forearm antenna to complete a directional antenna. The antennas when stored will have dense lead like covers around the zipper to protect them from EA (electronic attack) or detection.

The Soldier will place one arm straight up and unfold the system to the other arm, which will be bent upward at the elbow. The arm pointed straight up will have a base connection, which can touch the jawbone.

We will use technology now available in the Cell Phone Telecom Industry, which allows for non-verbal communication via the vocal cords vibrations and use the inner ear for direct transfer, with a micro recording device on the Shoulder of the soldier. It is theorized that this can be used for human sonar, hyperwave generation, microwave defense, communication, rescue, emergency or as a warning device.

For military it could be used within the battlespace for offensive or defensive operations.

Improving Reception With a Sirius Radio Antenna

With a Sirius radio antenna, you will never again experience poor radio reception. You will always have a smile on your face as you listen to your favorite radio programs, jazz music, or your favorite newscaster and commentators deliver their news and comments.

You will no longer suffer the inconvenience of constantly repositioning and repairing your twisted or damaged radio antennas. Once installed, it will provide you with uninterrupted radio service that no common antenna can provide you. This radio reception service will not only benefit you but your loved ones as well.

With one of these antennas you are assured that you have a better radio service, improved radio reception, and absolutely no more headaches.

There are also roof magnetic mounds that ensure excellent reception. With a Sirius radio antenna you are assured that you get products that are made using advanced technology and ensure better performance.

How can you maximize the benefits you can get from your Sirius radio antenna? First, know what you need. Do you need an antenna for your home? Or is it for your office, car, or boat? Then shop for models that are most appropriate for each location or use.

Study product manuals and installation manuals and make sure you follow the manufacturer’s instruction carefully installing your antenna.

There are antenna screens provided (depending on the model), so place them in locations where they are not blocked by buildings, trees, and screens. Avoid placing your antenna screens where there are objects that would deflect radio receptions, so you are always assured of excellent radio service.

For satellite radio reception, position your antenna screens towards the sky facing the south, as most satellites are located here.

When installing the antenna on your car, the best place to position it is on the trunk or on the roof of the car. This will ensure good radio reception.

Sirius radio antennas are safe and easy to install. When installed as instructed by the manufacturers it could give optimum radio service.

The Sirius radio antenna includes a variety of products that are practical, easy to install and use.

For information regarding Sirius radio antenna products and pricing visit their website. You can also search the Internet for local distributors.