Bryant Unlimited Go for Gold with New High Performance Cables

Bryant broadcast high precision video coaxes have all been designed to provide maximum bandwidth

With the current concentration of broadcast media preparations for the summer games in London, Bryant Unlimited have extended their own-brand  range of 75 Ohm digital coaxial video cables for high definition imaging for use up to 3Gb/s - 4.5 GHz

The following new designs were added:
BD SD50/53             SDI video cables (medium) 
BD SD50F/53F        Flexible SDI video cables (medium) 
BD SD10/13             SDI video cables (large) 
BD SD10F/13F        Flexible SDI video cables (large)

These cost-effective, European made SD-SDI, HD-SDI and 3G-SDI cables are constructed with gas-injected insulation, dual braid and tape screening and LSOH or PVC jacket materials to match the dimensions and performance levels of similar offerings.

Digital video cables must be dimensionally stable because any change in the designed distance between conductors and screen will alter the capacitance, hence, the impedance and the resulting return loss. Choice of insulating material is important because in a screened video cable, the insulator is the capacitor dielectric between core and screen and, the lower the capacitance; the less time it will take a signal to reach full amplitude.

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Bryant broadcast high precision video coaxes have all been designed to provide maximum bandwidth, stable impedance, low attenuation and low return loss to match the best in show.

They have been independently tested to guarantee HD performance and maximum cable length at HD-SDI (1080i) and exceed 3G-SDI (1080P SMPTE424M) with added legroom.

Bryant stock matching connectors for the whole cable range.

BD SD01 coaxial cables are designed for the transmission of HDTV and serial digital video signals and are equivalent to Image 360 and Belden 1855 ENH, and like all Bryant’s video cables have double shielding (one foil / one tinned copper braid). Digital signals include both high and low frequencies ~ braid screens are very effective below 10MHz and tape screens at higher levels.

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BD SD01 coaxial cables are designed for the transmission of HDTV and serial digital video signals and are equivalent to Image 360 and Belden 1855 ENH, and like all Bryant’s video cables have double shielding (one foil / one tinned copper braid). Digital signals include both high and low frequencies ~ braid screens are very effective below 10MHz and tape screens at higher levels.

Serial digital interconnect standards for calculated max. cable transmission length: 
SMPTE 259M (PAL, widescreen):       
Maximum length = 30dB loss at half the clock frequency 

SMPTE 292M (HDTV):       
Maximum length = 20dB loss at half the clock frequency 

This gives one method of defining the maximum calculated length of cable that provides satisfactory signal transmission. As the quarter wavelength of digital video is around 1500 times smaller than analogue, reflections caused by BNC connectors in the digital chain will affect return loss and attenuation.


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Simon Quill. Bryant’s Technical Manager says "Return loss is not just down to cables. Impedance mismatches from unsuitable connectors and patch bays can lead to signal reflections at high frequencies, so the use of 75 Ohm BNCs is crucial and can alter manufacturer’s claimed performance distances. Cable manufacturers tend to claim distance based upon differing parameters, which means the figures are often expressed on an apples vs. pears basis."

"Bryant tends not to make such statements since cables in Broadcast applications are seldom installed to their maximum claimed length. Rather, we test all manufacturers’ cables independently, so that we can be sure of their worth."

About Bryant Unlimited
Since 1982 the company has helped solve the 3 I's - Interconnection, Interface and Installation - of signal management in the Broadcast and Communication industries and has grown consistently to become the engineer's acknowledged service leader across those sectors.
The Bryant Unlimited catalogue contains 'best choice' solutions for the technical install, sourced from world leading manufacturers or designed and built in-house to solve the engineer's dilemma. Our facilities include modern metalwork fabrication, assembly and wiring workshops able to cope with most interface problems. As an example, Bryant Unlimited launched the first truly HDTV capable MUSA U-Link patch system, designed and built in the UK.

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The company is large enough to offer the best in service and product availability whilst small enough to still pay attention to detail at the design and manufacturing level.
Relocation to new warehouse and production facilities has enabled the addition of other areas of systems integration, including lighting and sound, IT networking, A/V and electrical installs to our product portfolio.

A truly single source supplier for everything needed to get audio or professional video signals from A to B via copper or fibre cables, connectors, power units, racks, metalwork, optical fibre, media converters, cable assemblies, jackfields, patch panels, data network products, monitoring and test equipment, Bryant Unlimited is dedicated to customer requirements, despatching products daily across the UK and worldwide with full export documentation.