For those who’ve been looking for all of Ron Hranac’s articles in one place, here they are: columns, features, and even the odd Webcast, from February 2003 to today. Articles are listed by date, most recent first. Just click on the headline to read the full story.

Ron is CT‘s senior technology editor and has been writing for us for more than 20 years. He’s been an SCTE member since 1979 and is currently a technical leader, Broadband Network Engineering, for Cisco Systems. Prior to joining Cisco, he held management positions at companies including High Speed Access International and Coaxial International. He also has held many positions on the SCTE board and in local chapters and has the distinction of being the first person in the cable industry to be certified in SCTE’s BCT/E program (in 1987) and became the SCTE’s first Fellow Member in 1991. 2008

Broadband: RF CNR vs. Baseband Video SNR
February 1, 2008
If one were to measure RF carrier-to-noise ratio (CNR) and baseband video signal-to-noise ratio (SNR) for the same analog TV channel, how would the numbers compare? This definitely falls into the "it depends" category. Much has been written over…

BROADBAND: Chemistry Class
January 1, 2008
How many times have you or someone you work with visited a subscriber s home in response to a service call about snowy pictures on some of the analog channels, and perhaps problems with some of the digital channels? The drop is disconnected from…

2007

Broadband: Service Availability
Dec. 1, 2007
For several years, I’ve said cable operators can provide reliable high-speed data, voice, and digital video services if the entire cable network – headend, distribution plant, and subscriber drops – meets or exceeds certain minimum technical…

Broadband: A Closer Look at BER, Part 2
Nov. 1, 2007
Let s say we want to ensure the BER – bit error rate or bit error ratio – at a cable modem s input is less than 1 x 10-8, also expressed as 1.0E-08. Recall from last month s column that transmitting three times the reciprocal of the specified BER…

Broadband: A Closer Look at BER, Part 1
Oct. 1, 2007
I’m occasionally asked about BER, one of several performance metrics used in the world of data transmission. Quadrature amplitude modulation (QAM) analyzers commonly report BER, as do some digital set-tops and cable modems. BER is an abbreviation…

Broadband: What’s Your CNR?
Sept. 1, 2007
"How many of you have measured the carrier-to-noise ratio (CNR) of downstream digitally modulated signals on your system?" When I ask that…

Broadband: Cable-Tec Expo Show Picks
Aug. 1, 2007
It was hot and humid, which is normal for Orlando in June. Thank goodness the Orange County Convention Center is air conditioned! That’s where more than 10,700 folks met for SCTE’s Cable-Tec Expo 2007, putting attendance up 6 percent from last …

DOCSIS 3.0
Aug. 1, 2007
The opportunities for cable operators provided by DOCSIS have been pretty much by the numbers: as in DOCSIS 1.0, 1.1, 2.0 and now DOCSIS 3.0. Version 1.0 got the data ball rolling; 1.1 added a number of features, including quality of service (QoS) …

Broadband: The Need for Speed
July 1, 2007
In the 1970s I teamed up with a friend to campaign a 1969 big block Chevy Camaro in what is known as ET bracket racing. This is old-fashioned quarter-mile drag racing, based on handicapped starts. Here’s how it works: Each driver makes several…

Digital Transmission, Part 2
July 1, 2007
Modulation error ratio (MER) is digital complex baseband signal-to-noise ratio (SNR) – in fact, in the data world, the terms "SNR" and "MER" are often used interchangeably, adding to the confusion about SNR, especially considering that, as…

Broadband: Big Numbers, Small Numbers
June 1, 2007
Ours is a world of numbers, and in cable we tend to use a lot of really big and really small numbers. Fortunately, there are several ways to simplify how we describe those numbers, which I’ll get to shortly. In reality, it’s hard to grasp just…

Digital Transmission, Part 1
June 1, 2007
Cable modem termination systems (CMTSs) can report a variety of operating parameters to the end user. For example, CMTSs that use Broadcom BCM3137, BCM3138, or BCM3140 or Texas Instruments TNETC4522 series upstream burst receivers can provide an…

Broadband: What’s a QAM?
May 1, 2007
Every industry has its own jargon, some of which is often incomprehensible to outsiders. This is certainly true of the cable industry. Much of cable’s terminology is technical in nature, making some of our favorite words, phrases, abbreviations and…

Broadband: Upstream 64-QAM Success Story
April 1, 2007
My September 2002 CT column, "16-QAM Success Story," started out with the following introduction: "It works great in the lab, but forget trying it in a real network." "QPSK barely works in my system, so there’s no way I can do 16-QAM." "We…

SCTE Active Status
March 1, 2007
It’s been quite awhile since I used this forum to get on my SCTE soapbox. Regular readers know that I’ve long been a supporter of SCTE and its programs and have even served on the Society’s national board and various …

Equalized or Unequalized? That Is the Question
Feb. 1, 2007
Equalized or unequalized modulation error ratio (MER), that is. The answer is, it depends. Let s back up a bit and look at the concept of equalization from the perspective of a coaxial cable distribution network. As you know, in a given length…

Modulation Error Ratio
Jan. 1, 2007
Awhile back I went target shooting with a friend. While at the range, it occurred to me that what is also known as plinking is a little like modulation error ratio (MER) used to characterize, say, the 64- and 256-QAM (quadrature amplitude…

2006

Migrating to All-Digital, Part 2
Dec. 1, 2006
The biggest logistical challenge in the move to all-digital operation will without a doubt be the process of migrating all of a system’s subscribers from analog to digital services. Most, if not all, subs will need a digital set-top box connected…

Migrating to All-Digital
Nov. 1, 2006
Over the past few years, the cable industry has been adding digitally modulated signals to the downstream spectrum to accommodate high-speed data, digital video, video-on-demand (VOD) and voice. A few operators have done something called digital…

The Power of QAM
Oct. 1, 2006
If you have an analog TV channel whose visual carrier level is 0 dBmV and a 6 MHz wide 64-QAM (quadrature amplitude modulation) signal whose digital channel power is 0 dBmV, which one has more power? Let s look at this subject more closely and see…

Troubleshooting Digitally Modulated Signals with a QAM Analyzer Sept. 21, 2006
Trilithic and Communications Technology are presenting a free Webcast Sept. 27 on troubleshooting digitally modulated signals with a QAM analyzer featuring Cisco Systems’ Ron Hranac…

One for the X-Files
Sept. 1, 2006
I recently heard from a regular reader about an interesting and somewhat unusual problem. Here’s the background. A defective downstream laser transmitter that serves three nodes was found to be causing degraded bit error rate (BER) in the…

Expo Show Picks
Aug. 1, 2006
Cable-Tec Expo 2006 has come and gone, and what a show it was. This year’s confab was held in the mile high city of Denver. A big tip of the hat to SCTE headquarters staff and the Expo Program Subcommittee for pulling off a successful event…

Self-Terminating Taps and Micro-Reflections
July 1, 2006
A Communications Technology reader recently sent me the following via email. "In your article `Linear Distortions, Part 1′ (July 2005, www.ct-magazine.com/archives/ct/0705/0705_lineardistortions.htm), you mention the use of self-terminating taps as…

Troubleshooting Digitally Modulated Signals, Part 2
July 1, 2006
Digitally modulated signals are a fact of life in the modern cable system, and keeping those signals healthy requires different equipment and knowledge than analog does. Here follows Part 2 of Ron Hranac’s Expo workshop on troubleshooting digitally…

Digital Troubleshooting, Part 1
June 1, 2006
Digitally modulated signals are used to transport high-speed data, video and voice on cable networks. These signals are subject to a variety of impairments that can seriously impact the quality and reliability of the services being provided. More…

More on Cable Modem Upstream Signal Levels
June 1, 2006
A couple weeks after I wrote last month s column, Cisco s John Downey took a look at the manuscript and suggested a few things to add to what was said. Since the May issue was well on its way through the editing and production process by then and…

Cable Modem Upstream Signal Levels
May 1, 2006
One of the easiest and more accurate ways to measure the amplitude of upstream digitally modulated signals from cable modems is to use a spectrum analyzer in zero span mode. Mark Millet and I coauthored an article about this in the Dec. 2000…

CMTS Upstream SNR Revisited
April 1, 2006
There was an interesting thread on the SCTE-List recently about cable modem termination system (CMTS) upstream signal-to-noise ratio (SNR). One cable operator reported having difficulty "obtaining upstream SNRs above the 25-26 dB range, even with…

DOCSIS 3.0
March 1, 2006
Since its introduction in the 1990s, DOCSIS (short for Data Over Cable Service Interface Specification) has emerged as the leading standard for high-speed data transmission over cable networks. DOCSIS 2.0 is the latest member of the DOCSIS family…

VoIP Service Calls
Feb. 1, 2006
It wasn’t that long ago that voice over Internet protocol (VoIP) telephony on cable networks was just "a couple years away." Not so any more. The first large-scale commercial rollout occurred nearly three years ago, and a fair number of cable…

Those Pesky Bit Errors
Jan. 1, 2006
Our downstream 64- and 256-QAM (quadrature amplitude modulation) signals are susceptible to all sorts of gremlins. Many impairments result in degraded bit error rate (BER) performance, which, if severe…

2005

Impedance Mismatches and Reflections
Dec. 1, 2005
In my Oct. 2005 column about return loss, I commented: An open circuit, short circuit or pure reactance terminating a transmission line are incapable of absorbing power from a forward, or incident…

Self Installs: Necessary or Unnecessary Evil?
Nov. 1, 2005
A few months ago, I was among the speakers at a Society of Cable Telecommunications Engineers-sponsored training seminar at one of a major cable operator’s systems. The subject of high-speed data self installs came up, and I expressed one of my…

Return Loss
Oct. 1, 2005
A few months ago, there was a discussion on the SCTE-List about return loss and whether it should be expressed as a positive or negative number. The answer? Positive number. Grab a cup of coffee, your scientific calculator, and read on to see why…

Downstream Power Measurements
Sept. 1, 2005
Ever wonder why we set the average power of a downstream digitally modulated signal several dB lower than what an analog TV channel would be on the same frequency? I like to ask this question at Society of Cable Telecommunications Engineers…

Expo 2005 Show Picks
Aug. 1, 2005
How do they manage to do it? I’ve attended every Cable-Tec Expo since the first one held in Dallas back in 1983, and each year’s confab is consistently better than the one before. Cable-Tec Expo 2005 was no exception, with robust exhibit hall floor…

Linear Distortions, Part 2
Aug. 1, 2005
Part 1 of this two-part series introduced the "invisible" but disruptive nature of linear distortions and covered recognizing and troubleshooting micro-reflections and amplitude ripple and tilt. We now pick up at adaptive equalization. Adaptive…

Linear Distortions, Part 1
July 1, 2005
One way to increase a cable network’s high-speed data and voice service throughput is to use higher orders of modulation. For instance, switching from quadrature phase shift keying (QPSK) to 16-QAM (quadrature amplitude modulation) will double the…

DOCSIS RFI
July 1, 2005
The Data Over Cable Service Interface Specification (DOCSIS) Radio Frequency Interface Specification includes a variety of assumed RF performance characteristics for downstream and upstream data channels, cable modem input and output, cable modem…

Online Resources
June 1, 2005
Ours is an information society, and cable is right smack in the middle of it. When it comes to tracking down information, the online world has become as valuable as the proverbial library bookshelf. This month, I’d like to share some of the online…

450,000 Words Later …
May 1, 2005
When I got my monthly email from Communications Technology magazine’s managing editor Ron Hendrickson with the "your May column is due on such-and-such date" message, I wondered about a suitable topic. It occurred to me that this month marks the…

Advanced PHY
April 1, 2005
In the latter part of 2002, I penned two columns discussing the then-new Data Over Cable Service Interface Specification (DOCSIS) 2.0, its support for greater per-channel upstream data throughput, two new multiple access technologies-advanced time…

Does Cable Need its own Geek Squad?
March 1, 2005
What comes to mind when you hear the term "home networking"? Installing one or more cable outlets in a subscriber’s home? Installing a cable modem and connecting it to a subscriber’s personal computer (PC)? Hooking up several PCs to a cable modem…

Confessions and a Great Customer Service Story
Feb. 1, 2005
I have a confession to make: I, um, just got cable modem service at home. "Welcome to the 1990s," you’re no doubt thinking. Oh, I had plenty of excuses for putting it off until now. The office is less than two miles from the house, and the…

Signal Leakage and VoIP
Jan. 1, 2005
One of the keys to ensuring reliable voice over Internet protocol (VoIP) deployments on the outside plant is a clean RF spectrum-that is, one free from over-the-air gremlins such as ingress and impulse noise. In theory, our networks are closed…

2004

BPL: The New Kid on the Block
Dec. 1, 2004
"They’re heeere …." We have a new competitor in the high-speed data arena: BPL, or broadband over power line. This technology goes by other names, including access BPL, power line communications (PLC), power line telecommunications (PLT) and…

Deploying VoIP on the Outside Plant, Part 2
Nov. 1, 2004
Last month’s column focused on the ability of high-speed data and voice to be deployed successfully on a network if the entire cable system headend, distribution network and subscriber drops meets certain minimum technical performance parameters…

VoIP Reliability
Oct. 1, 2004
Voice over Internet protocol VoIP is a popular topic these days. It’s gone beyond the "VoIP is still a couple years away" stage and is now being rolled out in a number of trials and even some full-blown deployments with paying customers. But there…

Making the Best Better
Sept. 1, 2004
For the past several months I’ve been perusing a new reference that’s found a home on my trusty engineering bookshelf: Modern Cable Television Technology: Video, Voice, and Data Communications, 2nd Edition, by Walter Ciciora, James Farmer, David…

Expo 04 Show Picks
Aug. 1, 2004
Cable-Tec Expo 2004 has come and gone, and the show once again exceeded expectations. The exhibit hall was packed to the rafters the first two days, and the technical workshops I sat in on were well-attended. Acterna sponsored the Arrival Night…

Wi-Fi Security
July 1, 2004
I have a confession to make: I’m a bandwidth thief. Let me explain. In the May 4th issue of PC Magazine, columnist John Dvorak discussed unsecured Wi-Fi (wireless fidelity, a term for wireless local area network) access points. Some people drive…

Digitally Modulated Carrier CNR
June 1, 2004
We have, for as long as I can remember, been concerned with carrier-to-noise ratio (C/N or CNR) in our networks. CNR, in cable industry vernacular, is a pre-detection measurement that is, a measurement made in the frequency domain. By definition…

Tackling Serious Ingress
May 1, 2004
Those of you who read this column regularly know that I’m a ham radio operator. I’ve written about ham radio-related interference in the past, most recently in the April 2003 issue…

Power and Grounding
April 1, 2004
I just returned from 2004 Power Council, an invitation-only conference hosted by Thomas & Betts (www.tnb.com). About 90 persons from cable, telco, power, direct broadcast satellite (DBS) and regulatory agencies made the trip to Tampa, Fla., to…

Microreflections and 16-QAM
March 1, 2004
You cleaned up the reverse, getting the carrier-to-junk ratio to a manageable 25~30 dB or better. Ingress and impulse noise are under control. The forward and reverse amps have been balanced. You moved the cable modem upstream digitally modulated…

Farewell, Memories and Western Show Picks
Feb. 1, 2004
If there s been one constant in our industry, it s change. One of those changes is the demise of the Western Cable Show, the last of which took place in December at the Anaheim Convention Center. It s hard to believe that just a few short years ago…

2003

Wordsmith
Dec. 1, 2003
Having written for Communications Technology since 1985, I’ve had the opportunity to work with some top-notch editors. They’ve taught me much about writing and editing, and I’ve managed to pick up some, uh, editor-type knowledge regarding the use…

IP Train
Nov. 1, 2003
SCTE’s Rocky Mountain Chapter recently sponsored a day-long technical seminar on the subject of IP Internet protocol. The seminar, held in Englewood, Colo., was well attended, and the three speakers covered the basics of IP, IP in the cable…

More on CMTS SNR
Oct. 1, 2003
In last month’s column I discussed carrier-to-noise ratio (CNR) versus cable modem termination system (CMTS)-reported signal-to-noise ratio (SNR). CMTSs that use Broadcom’s 3137 upstream burst demodulator silicon are capable of providing an…

Spectrum Analyzer CNR Versus CMTS SNR
Sept. 1, 2003
There are many ways to characterize the upstream performance of a two-way cable network and how it may impact the performance of a digitally modulated carrier. One time-tested method is to measure carrier-to-noise ratio (CNR) with a spectrum…

Frequency Offsets
Aug. 1, 2003
Every now and then a question comes up on the SCTE-List and at technical seminars regarding whether or not frequency offsets are required for downstream digitally modulated carriers operating on aeronautical frequencies. The short answer is no. Let…

EXPO ’03: Broadband Engineering Looks Fit in Philly
July 1, 2003
I don’t know how they manage to do it, but SCTE pulled off yet another Cable-Tec Expo that topped the previous year’s confab. Philadelphia turned out to be an excellent venue, with top-rated restaurants and local attractions for attendees and…

A Trip to the Library
June 1, 2003
I was looking at the bookshelves in my office the other day, and realized that out of literally hundreds of books and other reference material lining those shelves, a handful seems to get used way more than the rest. That’s not to say the others…

DOCSIS Set-top Gateway
May 1, 2003
When cable modems were introduced to the industry in the ’90s, the technology was proprietary. That is, a given vendor’s cable modem termination system (CMTS) and cable modems were incompatible with CMTSs and cable modems from other vendors. The…

Interference Report Card
April 1, 2003
Three years ago I wrote an article about signal leakage and interference to over-the-air users, specifically amateur ("ham") radio operators ("Signal Leakage & Harmful Interference," July 2000 Communications Technology.) I mentioned at the time that…

CNR Versus SNR
March 1, 2003
A recent discussion on the SCTE-List is the basis for this month’s column. The discussion had to do with the difference between carrier-to-noise ratio (C/N ratio or CNR) and signal-to-noise ratio (S/N ratio or SNR), and whether or not the Data Over…

Broadband Plus Show Picks
Feb. 1, 2003
As I write this, I’ve just returned from December’s "Broadband Plus, The New Western Show" in Anaheim, Calif. The convention’s name was changed to Broadband Plus for 2002, but word has it the new moniker will be dropped in 2003, and the confab once …

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