OSP Expert: Don McCarty

Some Clarification on DSL Testing


In a recent conversation with my friend and colleague, Ed Rousselot from Megger Corporation, he stated that he agreed with me on the process of provisioning and maintaining the copper infrastructure for bandwidth, but he felt that a significant amount of information could be gleaned about the health of the physical layer from DSL testing. Here is what Ed wrote to me: In the early 1970s I was trying, with little success, to get analog subscriber carrier working in Arkansas, and an old wire chief gave me some advice that is as true now as it was then. He slowly…

Delta Distributed Power and Its Effect on Telephone Circuits


I received an email from one of my telephone friends, Ed Rousselot from the Megger Corporation, bonding and grounding experts, and in it he stated: From Ed Rousselot: Donald, You may remember that during your session at OSP EXPO (2014), Chuck asked a question about why the telcos in California that are in areas served by Pacific Gas and Electric have been told to remove all attachments to what the telcos thought were (multi-grounded neutrals (MGNs). According to Chuck, PG&E says that the #6 wire coming down their power poles is not a true MGN, and having the telcos attach…

Creating a Copper Infrastructure That Can Compete and Win


The Quest for Quality Service The goal of all telephone companies is to get fiber-to-the-home for all customers. However, given the cost of replacing the copper infrastructure with fiber it will take years to accomplish this task especially in brownfield construction. Budget constraints force telcos to take a look at their existing copper infrastructure and at what can be done to provide maximum quality bandwidth. Therefore, for the near (and maybe distant) future, the condition of your copper infrastructure is the key in delivering quality service to your customer. Purchase the best switch that money can buy, reach the customer…

Over 30 Years With OSP Magazine


How Time Flies When You’re Getting Paid I started writing my column over 30 years ago in March. It seems like yesterday. I was with my good friend at an outside plant trade show in San Francisco, California, when I passed by the OSP booth. The first owner of Outside Plant Magazine, Jack Stober, grabbed me by the arm and said, “Donald, why don’t you write an article for Outside Plant Magazine?” I picked up the current issue, turned to my first article that I wrote for OSP and said, “Do you mean like this one?” He was unaware that…

Longitudinal Balance of a Copper Cable Pair and Its Effect on Bandwidth


To describe how longitudinal balance of a cable pair affects the circuit let’s look back in time. The first telephone circuits were telegraph lines or open wire (one-wire) circuits with ground as a return. In the late 1800s, electric streetcars were used in many cities. Because there was zero longitudinal balance on a one-wire circuit, unwanted frequencies and power influence (noise to ground) rendered the circuit useless. To solve the problem, the telephone companies converted to balanced circuits (tip and ring), which also reduced attenuation increasing the distance for telephone circuit. But, 2 wires strung side-by-side sharing the ground with…

A Quality Test Set for Construction Splicers


I’ve been on a kick writing about replacement multifunctional test sets for the Dynatel 965. In the process, I spoke with a provider of a set manufactured for construction conformance testing. Multifunctional test sets like the Dynatel 965, EXFO, JDSU, Megger, Copper Pro, and others, are used for conformance testing, but separate talk circuits and external tone sources have to be set up separately. One good answer to the problem is the AALogic D-105. The AALogic D-105 Construction Test Set was designed primarily for conformance testing by construction splicing technicians. It adds testing features necessary in today’s market to assure…

1 3 4 5 6