SDI video cables

Emelec VíasCom has SDI video coaxial cables, in several sections, designed to transport high definition video (HD-SDI and 3G-SDI) and 4K (6G-SDI and 12G-SDI).

We can divide them into two large groups:

With a single conductor that will provide the cable with a high performance. Suitable for fixed installations.
With multi-stranded conductor for flexibility and long life in mobile applications.

Which cable will best suit my needs? The resolution of the signal to be transmitted, as well as the working distance and the use of the cable will indicate the most suitable option.

Below we explain their characteristics and show you the different cables available in each of the two categories.

Description of SDI video cables

SDI video cables are coaxial cables consisting of a center conductor, which can be single or multi-core, an insulator, the outer conductor as shielding and the outer jacket.

Our SDI cables are made with oxygen free copper (OFC) or tinned OFC (OFC TC) conductors. The dielectric is high density polyethylene foam (FHDPE). The shield is different for each model, usually consisting of aluminum tape and tinned copper braid. The outer jacket is UL-PVC non-flame propagating.

All of them are specially designed for SDI digital video transmission, in all its categories. From the lowest definition ones governed by the SMPTE 259m standard and with a bitrate that varies between 143 and 360 Mbps, to the high definition HD-SDI and 3G-SDI defined by the SMPTE 292m and SMPTE 424m standards respectively, with a bitrate that reaches up to 1.5 Gbps in HD-SDI and 3 Gbps in 3G-SDI.

In addition, the larger section cables are also capable of carrying 4K-UHD 6G-SDI and 12G-SDI signals with bitrates of 6 Gbps and 12 Gbps, respectively. We refer to the Q11-234, Q5004 and Q11-243 multi-core cables and the Q11-3005, Q11-3006, Q11-3007, Q11-3008, Q11-3009 and Q11-3010 single-core cables as larger cross-section cables.

Cables with single conductor

Emelec has in stock 7 cables of different sizes with single core inner conductor prepared for the transport of SDI digital video signals. All of them are produced with OFC oxygen-free copper conductor and a double shield of Aluminium Tape and tinned copper braid with 90% coverage. The sections of each of them are detailed below.

Q11-3002 (0.132 mm² - 26AWG)
Q11-3003 (0,204 mm² - 24AWG)
Q11-3005 (0.270 mm² - 23AWG)
Q11-3006 (0.500 mm² - 20AWG)
Q11-3007 (0.785 mm² - 18AWG)
Q11-3008 (1,230 mm² - 16AWG)
Q11-3009 (2,010 mm² - 14AWG)

We have 3G and also 4K BNC connectors specifically designed to fit perfectly on our single core cables.

Multi-core conductor cables

Regarding multi-core cables, Emelec currently has 5 different models capable of transporting high definition SDI signals. The sections and screens used in each of them are detailed below.

Q11-75RGB (0.050 mm² - 30AWG, OFC TC spiral screen with 100% coverage)
Q11-252 (0.150 mm² - 26AWG, OFC TC braided shield with 85% coverage)
Q11-234 (0.350 mm² - 22AWG, OFC TC braid shield with 90% coverage)
Q5004 (0.630 mm² - 20AWG, Aluminum Ribbon and OFC braid shield with 100% coverage)
Q11-243 (0.880 mm² - 18AWG, Aluminum twin tape screen and OFC TC braid with 100% coverage)

We have 3G and also 4K BNC connectors specifically designed to fit perfectly on our multi-core cables.

Performance depending on the section and SDI signal to be transmitted

Depending on various parameters of each cable such as the conductor cross-section, the size of the materials used and their type among others, each transmission line is capable of carrying the different SDI signals through a maximum cable length.

This maximum length can be measured in two ways: one is by simulating the circuit by computer designing each cable to be analyzed virtually in a circuit simulator and the other is to test each cable in a real way using an SDI signal generator and a receiver that analyzes the received signal such as a waveform monitor.

Emelec VíasCom has carried out both tests and has grouped the results obtained in a table where the cable codes and the different SDI signals for which each cable has been tested are indicated. You can see the table below. The values in black indicate the result through the computer simulation and the results in green indicate the result through the real physical tests with each cable.

For the HD-SDI and 3G-SDI signals, a Blackmagic DeckLink SDI 4K video capture/transmitter card connected to a computer was used to generate the signal and a Tektronix WVR 8200 waveform monitor was used to process it.

In the case of 4K 6G-SDI and 12G-SDI signals, attenuation has been measured at the indicated frequencies for different cable lengths up to the maximum 40dB of attenuation established by the standards. For this purpose, the Keysight N9916A FieldFox network analyzer has been used both as a generator and to analyze the signal at the line output.

It should be noted that the real distance obtained is greater than that of the theoretical results, since the theoretical results indicate the recommended distance that will work in any case, whereas in the physical results we have taken each of our cables to the limit in a specific way and this has allowed us to find the maximum specific length for our particular cables.

Next we present the results obtained both theoretically (black colour) and physically (green colour) and the corresponding graphs.