Phone cables services are often referred to as landlines. These are phones that utilize analog to send and receive signals between two phones after they must have passed through some physical hardware that connects them.
The phone cable service is often seen as just a network of twisted copper wires with plugs attached to a wall. There are different types of hardware structure that a phone cable service might use depending on the needs of the business or office. A small business can easily opt for a 4-line system, but if more phone lines are required then PBX will be the best choice as it can serve up to 32 phone lines at the same time.
While some people might find phone cable services as outdated, they are still very reliable with features like call waiting, voicemails, caller ID and call blocking. The problem with phone cable service is space they take up and maintenance over time.
Voice Over Internet Protocol VoIP is a digital communication technology that allows you to make and receive calls over the internet.
Unlike the phone cable service that makes use of wire, VoIP makes use of the internet broadband made available through a router.
Most businesses are now adopting VoIP has it provide greater flexibility when it comes to the number of phone lines one can have. You can have an unlimited number of phone lines and the quality, distance covered are all dependent on the quality of the internet connection. VoIP is not limited by physical wires, hence it is less bulky and easier to maintain. Before you make a decision on which technology platform to use for your business you might want to consider the factors outlined below;.
Features: This is one of the most important factors to consider when deciding between VoIP and phone cable services. Both technologies can handle basic features like caller ID, call blocking, Voicemail, and many more. However, when it comes to more advanced options like virtual assistants, pre dialled contacts, call-to- email and more robust phone lines then VoIP is the best option. With VoIP business can also explore cloud computing and operate in multiple locations on the same network.
Cable broadband services contain adequate bandwidth to allow customers to talk on the telephone while using the Internet connection or watching cable TV. There should be no loss in performance if the system is installed correctly. Existing cable customers adding VoIP services may find discounts available from their cable company.
New cable customers will often find package discounts for bundling television, Internet and phone services that are installed and activated at the same time. All customers receive the benefit of having their television, Internet and phone services on a single bill. Telephone voice quality is excellent when making calls over cable networks. Often there are no additional charges to make domestic long-distance calls. In other parts of the world, these wires may be called "A" and "B".
Most installations have another pair of wires, yellow and black. These wires can be used for many different purposes, if they are used at all.
Some party lines use the yellow wire as a ground; sometimes there's 6. If you have two separate phone lines not extensions in your home, you will find the yellow and black pair carrying a second telephone line. In this case, black is "Tip" and yellow is "Ring. The above description applies to a standard line with a DC connection between your end of the line and the telephone exchange.
Most phone lines in the world are of this type, known as a "metallic line. Other types of lines are party lines, which may be metallic lines but require special telephones to allow the telephone company to differentiate between subscribers. Very long lines may have amplifiers, sometimes called "loop extenders" on them. Some telephone companies use a system called "subscriber carrier," which is basically an RF system in which your telephone signal is heterodyned up to around Khz and then sent along another subscriber's "twisted pair.
If you have questions about your telephone line, you can call your telephone company; depending on the company and who you can reach, you may be able to obtain a wealth of information. The standard network used all over the world is an LC device with a carbon microphone; some newer phones use discrete transistors or ICs.
One of the advantages of an LC network is that it has no semiconductors, is not voltage sensitive, and will work continuously as the voltage across the line is reduced. Many transistorized phones stop working as the voltage approaches 3 to 4 Volts. When a telephone is taken off the hook, the line voltage drops from 48 Volts to between 9 and 3 Volts, depending on the length of the loop. If another telephone in parallel is taken off the hook, the current consumption of the line will remain the same and the voltage across the terminals of both telephones will drop.
Bell Telephone specifications state that three telephones should work in parallel on a 20 mA loop; transistorized phones tend not to pass this test, although some manufacturers use ICs that will pass. Although some European telephone companies claim that phones working in parallel is "technically impossible," and discourage attempts to make them work that way, some of their telephones will work in parallel.
While low levels of audio may be difficult to hear, overly loud audio can be painful. Consequently, a well designed telephone will automatically adjust its transmit and receive levels to allow for the attenuation - or lack of it - caused by the length of the loop. This adjustment is called "loop compensation. Although some telephones using ICs have built-in loop compensation, many do not; the latter have been designed to provide adequate volume on the average loop, which means that they provide low volume on long loops, and are too loud on short loops.
Various countries have different specifications for transmit and receive levels; some European countries require a higher transmit level than is standard in the United States so a domestically-manufactured telephone may suffer from low transmit level if used on European lines without modification.
Because a telephone is a duplex device, both transmitting and receiving on the same pair of wires, the speech network must ensure that not too much of the caller's voice is fed back into his or her receiver. This function, called "sidetone," is achieved by phasing the signal so that some cancellation occurs in the speech network before the signal is fed to the receiver.
Callers faced with no sidetone at all will consider the phone "dead. Can you hear ME? A telephone on a short loop with no loop compensation will appear to have too much sidetone, and callers will lower their voices. In this case, the percentage of sidetone is the same, but as the overall level is higher the sidetone level will also be higher. There are two types of dials in use around the world. The most common one is called pulse, loop disconnect, or rotary; the oldest form of dialing, it's been with us since the 's.
In the U. MF means single tones used for system control. Pulse dialing is traditionally accomplished with a rotary dial, which is a speed governed wheel with a cam that opens and closes a switch in series with your phone and the line.
It works by actually disconnecting or "hanging up" the telephone at specific intervals. The United States standard is one disconnect per digit, so if you dial a "1," your telephone is "disconnected" once. Dial a seven and you'll be "disconnected" seven times; dial a zero, and you'll "hang up " ten times.
Some countries invert the system so "1" causes ten "disconnects" and 0, one disconnect. Some add a digit so that dialing a 5 would cause six disconnects and 0, eleven disconnects. There are even some systems in which dialing 0 results in one disconnect, and all other digits are plus one, making a 5 cause six disconnects and 9, ten disconnects. Some modern digital exchanges, free of the mechanical inertia problems of older systems, will accept a PPS rate as high as This is the pulse measured at the telephone, not at the exchange, where it's somewhat different, having traveled through the phone line with its distributed resistance, capacitance, and inductance.
Bear in mind that each pulse is a switch connect and disconnect across a complex impedance, so the switching transient often reaches Volts.
Try not to have your fingers across the line when dialing. Instead of pushing your finger round in circles, then removing your finger and waiting for the dial to return before dialing the next digit, you punch the button as fast as you want.
Because the IC has already stored the dialed number in order to pulse it out at the correct rate, it's a simple matter for telephone designers to keep the memory "alive" and allow the telephone to store, recall, and redial the Last Number Dialed LND. This feature enables you to redial by picking up the handset and pushing just one button. Because pulse dialing entails rapid connection and disconnection of the phone line, you can "dial" a telephone that has lost its dial, by hitting the hook-switch rapidly.
It requires some practice to do this with consistent success, but it can be done. A more sophisticated approach is to place a Morse key in series with the line, wire it as normally closed and send strings of dots corresponding to the digits you wish to dial.
Touch tone, the most modern form of dialing, is fast and less prone to error than pulse dialing. Compared to pulse, its major advantage is that its audio band signals can travel down phone lines further than pulse, which can travel only as far as your local exchange. Touch-tone can therefore send signals around the world via the telephone lines, and can be used to control phone answering machines and computers. Bell Labs developed DTMF in order to have a dialing system that could travel across microwave links and work rapidly with computer controlled exchanges.
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