Connectors for HDTV
High Definition Television (HDTV) digital technology places high demands on the components used. The improved picture quality goes hand in hand with significantly higher amounts of data. In order to be able to transmit these with minimum losses, high-quality 75 Ohm BNC and F connectors as well as special cables were developed for radio and studio applications, which have the most exact possible impedance matching.
Depending on the application, Telegärtner offers two HDTV-compatible versions of its BNC connectors. The first variant has a rotatable bayonet slot and is more intended for indoor use. When plugged in, these plugs comply with IP54 transverse tightness.
The second variant - BNC EasyGrip HD³ - has a one-piece body. These connectors are mechanically more stable, allow a higher packing density and achieve a protection class of at least IP67 when plugged in. This makes these connectors particularly suitable for outdoor use.
HDTV suitable cables
Where high quality 75 Ohm cables are concerned, the greatest challenge lies especially on the production front. Here, it is imperative to ensure as accurately as possible the interaction of wire pre-heating, nitrogen and material feed, temperature control, speed control of the extruder, as well as control of the unwinding and winding. High uniformity of the line speed and compliance with a defined cooling process is important to keep production tolerances as low as possible. In addition, the prevention of vibration of the inner conductor being fed into the extruder is vital. When all of these parameters are observed, an impedance accuracy of 75 Ohm < +1% can be achieved.
Greater data volumes for better picture quality
Since the 30th of April 2012, analogue satellite TV has been history in Germany, and digital TV (Digital Video Broadcasting) has entered out living rooms. DVB can be received via cable (DVB-C), satellite (DVB-S) and terrestrial antennae (DVB-T). This changeover has brought us improved picture quality which is more than apparent in HDTV (High Definition TeleVision) broadcasts. These HD broadcasts have at least 720 picture lines, whereas PAL (Phase-Alternation-Line) only has 576 picture lines (analogue/digital). But the data volume that has to be transmitted within a certain time also increases with the higher picture quality. The data rate for HDTV can be up to 25 Mbit/s per channel, whilst normal PAL data rates are 4 or 6 Mbit/s per channel.
The high quality 75 Ohm BNC and F-connectors, as well as cables, specially developed for radio and studio applications, have been designed to match the impedance as accurately as possible, and therefore enable transmission of such large data volumes with minimum losses.
The better adaptation to the impedance results in significantly better return loss values for the HDTV-compatible BNC connectors compared to a 75 Ohm standard BNC connector.