E1 and Datacom Testing

E1 and Datacom Testing

Despite the growth of IP over Ethernet services, E1 (G.703/G.704) and Datacom services such as X.21 are still widely used in broadcast, power network, railway, air traffic control and network timing applications. The problem however for users looking for test equipment for these technologies is that many manufacturers no longer provide support for E1 or Datacom, and for those that do, the test capability is often severely limited.

There is good news however, Albedo Telecom are one of the only suppliers with a current product line that not only supports E1 and Datacom testing, but offers advanced testing features and capability for these technologies not found on other products.

The AT.2048 is the ultimate BER analyser and generator for E1, Datacom, Jitter, Wander, Pulse mask, Frame Relay, VF, and more. The AT.2048 is truly rugged and is ideal for field engineers installing and maintaining E1 and Datacom circuits. Designed with the latest technology, it is light, fast, friendly and provides comprehensive test capabilities, all at an unbeatable price.

The Albedo Ether.Genius and Ether10.Genius multi technology testers are equipped with all the features you need in order to install and maintain telecom networks based on E1/T1, Datacom, C37.94, Precision Time Protocol (PTP IEEE 1588), Gigabit Ethernet (GbE), 10 Gigabit Ethernet, Synchronous Ethernet and Jitter/Wander.

One Way Delay Testing on E1 and Datacom Circuits

In some applications such as Power Protection Systems, one way network delay and delay asymmetry measurements are critical to ensure correct operation of protection relays and other equipment. Often legacy  4-Wire VF, X.21, E1 and specialised C37.94 circuits are used for the communications in these systems.

The Ether.Genius product range offers a unique capability in being able to perform OWD and Asymmetry measurements across all these interfaces using an external GPS timing source. The internal oscillator of the Ether.Genius is trained by the external GPS timing source and a specially formatted time signal is then transmitted across the interface. At the far end the time signal is received on the chosen interface. decoded and compared to the oscillator time which itself has been trained from the external GPS timing source allowing for highly accurate One Way Delay and Asymmetry measurements.

Optional OCXO and Rubidium clocks can be specified for the Ether.Genius, these allow the units to measure OWD and Asymmetry without a GPS signal once the timing is locked, making it ideal for measurements in equipment rooms and locations where receiving a GPS signal is impossible.

 

E1 Pulse Mask Testing

E1 signals often fail to meet the ITU-T G.703 pulse mask specification leading to service operation issues, this can be due to problems such as long and short cable lengths, wrong impedances or signal interference. Pulse Mask Screen

Both the AT.2048 and Ether.Genius have the ability to test and verify E1 G.703 input signals, automatically comparing signals to the ITU-T G.703 pulse mask. The Positive and Negative pulses are checked and the user is provided with a graphical signal display with Pass or Fail indication, helping users identity and troubleshoot signal issues.

 

Jitter & Wander Generation & Analysis

For network equipment to correctly interpret incoming digital signals it must be able to synchronise its receiver circuity to the incoming data stream. On E1 circuits equipment will often recover clocking information from the received data and in turn use the clock source for it own transmitters. However frequency and timing deviations can occur, which leads to clock synchronisation problems and errors.

TIETiming and phase deviations on a digital signal is called Jitter and very slow Jitter (below 10Hz) is called Wander. Jitter can be caused by oscillator drift, impulsive noise, crosstalk, delay fluctuations and other influences . It is important to be able to measure Jitter and Wander on E1 circuits in order to verify clock accuracy and eliminate potential problems. As important is the ability to be able to generate Jitter and Wander to test that equipment is also able to operate within certain Jitter and Wander tolerances without error.

To get more details on the AT.2048Ether.Genius or Ether10.Genius

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