Black Box Explains...PC, UPC, and APC fiber connectors.
Fiber optic cables have different types of mechanical connections. The type of connection determines the quality of the fiber optic lightwave transmission. The different types well discuss here are the... more/see it nowflat-surface, Physical Contact (PC), Ultra Physical Contact (UPC), and Angled Physical Contact (APC).
The original fiber connector is a flat-surface connection, or a flat connector. When mated, an air gap naturally forms between the two surfaces from small imperfections in the flat surfaces. The back reflection in flat connectors is about -14 dB or roughly 4%.
As technology progresses, connections improve. The most common connection now is the PC connector. Physical Contact connectors are just thatthe end faces and fibers of two cables actually touch each other when mated.
In the PC connector, the two fibers meet, as they do with the flat connector, but the end faces are polished to be slightly curved or spherical. This eliminates the air gap and forces the fibers into contact. The back reflection is about -40 dB. This connector is used in most applications.
An improvement to the PC is the UPC connector. The end faces are given an extended polishing for a better surface finish. The back reflection is reduced even more to about -55 dB. These connectors are often used in digital, CATV, and telephony systems.
The latest technology is the APC connector. The end faces are still curved but are angled at an industry-standard eight degrees. This maintains a tight connection, and it reduces back reflection to about -70 dB. These connectors are preferred for CATV and analog systems.
PC and UPC connectors have reliable, low insertion losses. But their back reflection depends on the surface finish of the fiber. The finer the fiber grain structure, the lower the back reflection. And when PC and UPC connectors are continually mated and remated, back reflection degrades at a rate of about 4 to 6 dB every 100 matings for a PC connector. APC connector back reflection does not degrade with repeated matings. collapse
Black Box Explains...Digital Visual Interface (DVI) cables.
The Digital Visual Interface (DVI) standard is based on transition-minimized differential signaling (TMDS). In a typical single-line digital signal, voltage is raised to a high level and decreased to a... more/see it nowlow level to create transitions that convey data. To minimize the number of transitions needed to transfer data, TMDS uses a pair of signal wires. When one wire goes to a high-voltage state, the other goes to a low-voltage state. This balance increases the data-transfer rate and improves accuracy.
There are different types of DVI connectors: DVI-D, DVI-I, DVI-A, DFP, and EVC. DVI-D is a digital-only connector.
DVI-D is a digital-only connector. DVI-I supports both digital and analog RGB connections. Some manufacturers are offering the DVI-I connector type on their products instead of separate analog and digital connectors. DVI-A is used to carry an analog DVI signal to a VGA device, such as a display. DFP, like DVI-D, was an early digital-only connector used on some displays; it’s being phased out. EVC (also known as P&D) is similar to DVI-I only it’s slightly larger in size. It also handles digital and analog connections, and it’s used primarily on projectors. collapse
Product Data Sheets (pdf)...Telephone Line Managers
- Pdf Drawing...
Fiber Optic Coupling (SC%X96SC, Rectangular Mounting) PDF Drawing
PDF Drawing for the FOT118 and FOT120
- Pdf Drawing...
Fiber Optic Coupling (MT-RJ%X96MT-RJ, Rectangular Mounting with Cap) PDF Drawing
PDF Drawing for the FOT121