Three quality services in one bundle with one bill are very attractive to consumers. The customer has one bill, one company, one contact, and one field technician. The opportunity for customer satisfaction is at maximum and, when it works, customer frustration would be at a minimum. But a key success factors to customer satisfaction is a knowledgeable technician and timely service.

Computerized Testing at the Central Office or the Remote
The field technician’s approach to trouble shooting will depend upon whether or not his company provides computerized testing of the DSLAM and the video input all the way back to the head-end equipment. Computerized testing provides a wealth of information to help in trouble shooting. This test equipment installed at the central office (CO) or remote can split the circuit at the DSLAM, emulate Triple Play end devices, and look in to the DSLAM or out to the modem. Some systems will test to see if the information is getting to the DSLAM from the head-end equipment.

Having the ability to split the customer’s circuit at the DSLAM quickly isolates the trouble as “in” or “out”. This solution provides immediate service quality feedback and rapid trouble diagnosis. By emulating the customer’s modem they can connect to the DSLAM port and see if
it is functioning properly, then attempt to connect to the customer’s modem and sync.

If the customer’s modem does not sync the system, then the testing system will do a narrow band POTS test to identify problems that affect customer modem sync. If the modem does sync, then the system can test for fast rate, maximum achievable rate, the signal-to-noise ratio, and the attenuation.

If the testing system cannot sync with the customer’s modem, it can then test for major DC type faults, shorted or grounded cable pairs, crossed battery from other circuits, capacitive unbalance, and disturbers that cause cross talk (T1, HDSL, and ADSL cross talk). The system also tests for AC interference on the cable pair such as harmonics from the distribution power and high frequency interference from AM radio, ham radio, and short wave radio.

Without Computerized Testing at the Central Office or Remote
This process removes a great burden from the field technician, and it removes the opportunity for human error in this part of the process. Without this capability companies are forced to go to the “when in doubt, dispatch out” process. Someone, usually the field technician, has to go to the DSLAM port with a modem and check for sync. The problem with this process is that there is no cable pair impedance and the port does not get stressed. It may sync and stabilize at the port, and then not stay in sync at the customer with the cable pair impedance added to the circuit.

Some field test sets allow the field technician to open the pair, emulate the DSLAM to check for sync, and if no sync, then they can do a narrow band POTS test. Most good multi-functional Triple Play test sets have a good digital multi-meter to identify DC type faults, an open meter to test capacitive balance, and a Time Domain Reflectometer (TDR) to identify the presence of bridged tap and its approximate location. They also have a spectrum analyzer that identifies cross talk from disturbers and identify interferers.

Must Have Quality POTs
Keep in mind that three services are using one cable pair, so make sure that the circuit will support quality POTS service. The cable pair should be free of DC type faults with acceptable longitudinal balance within the reach of IPTV service. The cable shield should have continuous bonding to mitigate high frequency AC interferers such as AM radio, ham radio, and short wave radio, and be periodically connected to the distribution power neutral to mitigate AC interference.

The customer Network Interface should be checked visually to see that it is attached to the power ground electrode and should test from 0 to 25 ohms with the shield of the buried drop disconnected. At the Network Interface the loop current should be greater than 23 Ma, Circuit Loss should measure less than 8 dBm, Power Influence should measure less than 80 dBrnC, Circuit or Metallic Noise should measure less than 20 dBrnC, and the longitudinal balance should calculate to greater than 60 dB. (I and a couple of noise mitigation experts believe that it should be greater than 70 dB.)

Poor longitudinal balance is also caused by series resistance, wet air-core cable pairs, and split cable pairs. A grounded short on the cable pair on one end and tested from the other end will identify series resistance. It first will fail the longitudinal balance test and when measured in ohms, the tip or ring conductor will read long. A TDR will identify and show the approximate distance to the series resistance.

A split cable pair can be identified by placing identification tone on the pair and using an amplifier in the cable count. Other pairs will have less tone, and the conductor that is split with your circuit will have the same amount of tone on it as your pair. Use a TDR set to the cross-talk feature to identify and show the approximate distance to the splice where the split occurred.

When testing from the Network Interface in any crossed battery, short, ring or tip ground or series resistance, staples in inside wire, loose connections, faulty jacks, or base cords should be repaired or replaced. With a grounded short at the Network Interface and a good ground from a tested power outlet in the vicinity of the jack, any series resistance can be identified and repaired.

At the customer’s modem when the fast rate and the maximum achievable rates are tested and proven acceptable, the signal-to-noise ratio should be no less than 9 dB for IPTV and the attenuation should be no greater than 24 dB for HD.

All AC outlets in the residence that are used for IPTV should be tested to show they are wired correctly with no open grounds. That includes outlets used for computers, fax machines, televisions, and audio equipment such as surround sound systems.

In most instances if the customer meets or exceeds the above parameters they will have a quality Triple Play service, and a happy customer who won’t leave for the competition.

Signing off
It has been a challenging year for many due to the war, the economy, and the presidential election. I know many of us were personally affected by these tough times. Let’s hope we have an improved climate in 2009. My best to all of you loyal readers for a wonderful holiday time. Remember to email your questions and your tough problems: dmccarty@mccartyinc.com, or call 831.818.3930, and visit my website: www.mccartyinc.com.