fiber optic

Every type of cable has a maximum distance. These distance limits can vary greatly from one type of cable to the next. Along with determining whether a cable will work, distance limits will also determine how well a cable works. Knowing the fundamentals behind cable distance limits is the first step in selecting the best cable for your needs.

Cables will always have some sort of “maximum signal” rating, depending on the type of the cable. For Ethernet cables, it will be the maximum upload/download speed. For HDMI cables, it will be the maximum resolution of the video. And so on and so forth for other cables. Any type of “maximum” rating should be taken with a grain of salt.

Those ratings are the best possible rating the cable is capable of under theoretical, perfect conditions. For example, modern HDMI cables are all rated for 4k. But if the HDMI cable is running through a coupler, users will almost certainly not get 4k. Each time a signal passes through a connection, even just connecting a cable to something like a TV or computer, the signal quality degrades a little. Using devices like extenders and couplers will make the signal weaker; for example, coupling a 10’ cable to a 5’ cable will result in a weaker signal than just using a single 15’ cable. Here is where HDMI baluns can help.

Another key factor for signal quality is the distance of the cable. The further a signal has to travel, the more it will degrade by the time it gets from Point A to Point B.

Fiber optic cable is the newer, faster way to transmit data. These send data signals using light (lasers) instead of electricity. Light signals can travel faster for higher bandwidth, suffer from less signal loss, and degrade less from electrical interference. Fiber optic cables come in a few different varieties with multiple types of cable as well as multiple connectors.

Types of cable include:

• Single-mode
• Multi-mode
• OM1
• OM2
• OM3
• OM4

Types of connectors include:

• FC
• LC
• SC
• ST
• MTP/MPO
• MTRJ

Fiber Cables

Single-mode

Single-mode fiber optic contains a very thin core, making it ideal for long-range transmissions. These cables can be incredibly long, with a single line potentially running for miles. The light transmitted by single-mode cable is between 1,300 and 1,550 μm, a frequency range that almost puts it into the infrared wavelength. This version of fiber optic cable is mainly used for telecommunications.

The name “single-mode” comes from the cable only transmitting a single mode of light down the cable. Typically, single-mode fiber optic is color coded yellow. The downside of single-mode is that their long range means they require very powerful lasers to operate at those extreme distances. The equipment needed to make lasers that powerful tends to be very expensive.

Multi-mode

Multi-mode fibe