Video over koax-kabel: Rækkevidden forøges med en faktor 5
Ny videoequalizer gør det muligt at overføre højkvalitets billeder over en afstand på op til omkring 1,7 km. via standard Cat 5 eller koax-kabler (in english).
Intersil has introduced what the company claims is the industry's most innovative and versatile single channel adaptive equalizers for delivering composite video through cables.
The Intersil 'MegaQ' devices are designed to automatically equalize video over the popular and inexpensive Cat 5 cable as well as the more traditional coaxial cable. The MegaQ devices deliver outstanding composite video images at distances over five times those currently possible, with a maximum length of 1 mile or 1.67 kilometers.
These adaptive equalizers enable cameras or video displays to be placed in remote areas, eliminating the need for repeaters and distribution hubs, making the family ideal for the security market or any application using composite video. In addition to its remarkable performance, the MegaQ family requires no user interaction or adjustments to get the best performance, so video quality is no longer dependent on the installer.
Adaptive equalization takes place on the receive end of the signal chain where images are viewed, so a MegaQ equalizer can easily be added to existing installations, instantly improving image quality. MegaQ does not require any active circuitry at the transmission (or camera) end, so cameras already at remote sites or mounted on buildings or poles do not need to be retrofitted. The ISL59605 compensates for high frequency cable loss up to 60dB at 5MHz, as well as source amplitude variations up to ±3dB.
Every device is automatically compatible with NTSC and PAL, color and monochrome, with no hidden caveats. Inputs are AC-coupled and internally DC-restored to maximize common mode noise rejection. The output can drive 2VP-P into two source-terminated 75? loads. The equalizers require a single +5V supply and consume only 500mW.
The MegaQ family continuously monitors the cable characteristics and compensates for long-term cable aging. Several optional locking modes are available to help maintain lock in noisy environments. An optional serial interface on each device provides signal monitoring.
The ISL59601, ISL59602, ISL56903, ISL59604, and ISL59605 are sampling now in compact 4x4 20-lead QFN packages.
To support the MegaQ family, two demonstration boards are also available. The ISL5960X-EVALZ is a compact, stand-alone demonstration board solution available at $250.00. The ISL5960X-SPI-EVALZ provides user access to the SPI interface for signal monitoring and is available for $350.00.
http://www.intersil.com/Video/MegaQ.asp
