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KH6JRM's Amateur Radio Blog
Amateur Radio--news, analysis, discussion, and antennas
Curated by Russ Roberts
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Four new ARRL Section Managers elected

Four new ARRL Section Managers will take office on July 1. Ballots were counted May 20 at ARRL HQ for contested races in the spring SM election cycle (Amateur Radio - Four new ARRL Section Managers elected: Four new ARRL Section Managers will ta...
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Congratulations to our new Section Managers.  These volunteers are important people in the ARRL Field Organization.  They are your direct contact with ARRL Headquarters on all things pertaining to Amateur Radio in your local area.  Please support them and help spread the word of amateur radio.  Aloha de Russ (KH6JRM).

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Introducing SmartMic Ham Radio Digital Voice

David Rowe VK5DGR and Rick Barnich KA8BMA have been working on SmartMic, an embedded hardware product that allows you to run FreeDV without a PC.
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This is a truly great idea!  Considering the cost of some digital voice equipment, the system developed by David Rowe (VK5DGR) and Rick Barnich (KA8BMA) be a winner.  David and Rick developed the "SmartMic" from the STM32F4 microcontroller.  The device has a "built in microphone, a speech amplifier, and transformer isolated interfaces to your radio.  Production is set for later this year.  The price will be $195.  Aloha de Russ (KH6JRM).

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Broadcast Engineering Tutorial for Non Engineers.pdf - File Shared from Box

Broadcast Engineering Tutorial for Non Engineers.pdf - File Shared from Box | KH6JRM's Amateur Radio Blog | Scoop.it

Via David Hall
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This is the tutorial I wish I had when I was doing transmitter and studio maintenance for Pacific Radio Group (Hilo, Hawaii).  This guide from Elsevier, Inc. covers everything from digital and analog audio to information technology.  The 328 page pdf has just about everything you need for your technical library.  There's a lot of material useful for amateur radio operators, too.--especially in the explanation of digital television and audio.  Great stuff.  Thanks to reporter David Hall for this lead.  Aloha de Russ (KH6JRM).

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National Hurricane Center Annual Station Test Set for May 31 - ARRL

National Hurricane Center Annual Station Test Set for May 31 - ARRL | KH6JRM's Amateur Radio Blog | Scoop.it
National Hurricane Center Annual Station Test Set for May 31 ARRL “The purpose of this event is to test Amateur Radio Station equipment, antennas and computers prior to this year's Hurricane Season, which starts June 1 and runs through November...
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The National Hurricane Center's amateur radio station WX4HNC will conduct a test of its network on 31 May 2014, from 1300 UTC to 2200 UTC.  This is not a contest, but rather a familiarization session for those involved in reporting tropical storms and hurricanes.  Hurricane season runs from 01 June 2014 to 30 November 2014.  Aloha de Russ (KH6JRM).

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KB9VBR J-Pole Antennas

KB9VBR J-Pole Antennas | KH6JRM's Amateur Radio Blog | Scoop.it
Amateur Radio, Land Mobile, Scanner, Low Power FM, and Airband Antennas.
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An nice explanation of the merits of a J-Pole antenna for both emergency use and for those "space challenged" at home.  Michael Martens (KB9VBR) says there are three reasons to choose a J-Pole over a 1/4 wavelength vertical for 2 m and 70 cm use:  relatively small size, a respectable 2.5 dB gain over a 1/4 wavelength vertical, and moderate cost.  I have a homebrew J-Pole and it works very well.  If you can't "roll your own", send an email to Michael.  He has several models that will fit your budget.  Aloha de Russ (KH6JRM).

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Shin-En2 Satellite Linear Transponder Frequencies

Shin-En2 Satellite Linear Transponder Frequencies | KH6JRM's Amateur Radio Blog | Scoop.it
The IARU Amateur Satellite Frequency Coordination Panel has announced frequencies for the Shin-En2 linear transponder. Shin-En2 is a 2.85 kg satellite measuring 490×490×475 mm built by students at ...
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If all goes as planned, the Shin-En2 satellite from Kagoshima University in Japan will launch in the 4th quarter of 2014.  The IARU has released the frequencies for this bird:

 

Coordinated Frequencies--437.505 MHz (CW beacon).  437.385 MHz (WSJT telemetry).  Inverting SSB/CW transponders--145.940-145.960 MHz (uplink LSB).  435.280-435.260 MHz (downlink LSB).

 

What makes this satellite unusual is its orbit.  According to the IARU Amateur Radio Satellite Frequency Coordination Panel, Shin-En2 will "have an elliptic orbit around the sun and travel to a deep space orbit between Venus and Mars."  This should be an exciting satellite to monitor.  Aloha de Russ (KH6JRM).

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FCC Report Says Cable Rates Rising Rapidly

 

According to a report from the Federal Communications Commission, cable bills are continuing to rise, at a rate 4 times faster than inflation, even with competition.
Why This Matters: Programming costs are big part of rising bills and according the FCC study, the price per-channel for subscribers rose 2.1% to an average of 48 cents per channel. The average monthly price for expanded basic service was $64.41 in 2012, a 5.1% increase over 2011, the regulatory agency said. The Consumer Price Index rose just 1.6% during the same 12-month period.


Via David Hall
Russ Roberts's insight:

Thanks to reporter David Hall for this tasty tidbit from the FCC.  This comes as no surprise.  Frankly, I cut the cord years ago.  I can't see paying for services I rarely use.  Besides, with the exception of a few sports, historical, and news programs, most of what I see offered holds little interest for me.  My needs are simple and my life style even plainer.  If I need a tv program, such as news or a championship game, I turn to my deep fringe Winegard TV antenna and my digital converter box.  The picture quality is acceptable for over-the-air transmissions.  If I have to see a current movie, there is always Netflix, Hulu TV, or even the public library.   As for high tech playthings, my ham shack has enough projects, repairs, and equipment to keep me busy for years.  There are too many distractions.  All of these gadgets are becoming a type of electronic "drug" that dulls the senses and removes us from the real world, ugly and disappointing as it is.  If I need a fairly cheap drug, I go to the refrigerator and grab a bottle of the local brew or, as the oldtimers once called such refreshments, an "807."  Aloha de Russ (KH6JRM).

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Ham radio: Old technology gets new respect - Fox News

Ham radio: Old technology gets new respect - Fox News | KH6JRM's Amateur Radio Blog | Scoop.it
Ham radio: Old technology gets new respect
Fox News
ATLANTA – Seeking reliable backup communication in a crisis, emergency managers are finding new solutions in an old technology: ham radio.
Russ Roberts's insight:

A pretty decent article from Fox News describing how hospitals are joining other public service agencies in using amateur radio to provide back up communications capability in the event of natural or man-made disasters.  Herb Schraufnagel, the public safety captain with Emory University Hospital Midtown, says many hospitals have learned a valuable lesson from  the hurricanes, tornadoes, and floods which have lashed the country in recent years.  He adds that ham radio is valuable tool--"it's just another avenue, another opportunity for us to be able to communicate."  Amateur radio operators can make themselves even more useful by getting certified in First Aid, CPR, and in the FEMA disaster protocols.  There are several online courses that will bring you up to speed.  Aloha de Russ (KH6JRM).

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G0KYA's Amateur Radio Blog: An Introduction to Antenna Modelling

G0KYA's Amateur Radio Blog: An Introduction to Antenna Modelling | KH6JRM's Amateur Radio Blog | Scoop.it
G0KYA's blog devoting to amateur radio / ham radio, featuring articles on antennas, propagation, marconi and much more.
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Steve Nichols (G0KYA) has just released a new book called "An Introduction to Antenna Modelling."  According to Steve, the book "lts you design and optimise a whole host of antennas--all on your PC.
When you finish the book, Steve believes you will be able to model a wide range of antenna, including dipoles, verticals, magnetic loops, WB3EDD, G5RV, and more.  The book contains a free CD with software covering MMANA-GAL, EZNEC, MIMNEC Pro, and 4nec.2.  You can order through Amazon.com.  Aloha de Russ (KH6JRM). 

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IOTA news from OPDX | Southgate Amateur Radio News

IOTA news from OPDX | Southgate Amateur Radio News | KH6JRM's Amateur Radio Blog | Scoop.it
Weekly IOTA News - compiled by Tedd Mirgliotta, KB8NW (RT @enzo_log: rt: @SAR_News IOTA news from OPDX | Southgate Amateur Radio News http://t.co/qCDgTEls2X #hamradio #hamr)...
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Thanks to Tedd Mirgliotta (KB8NW) for this IOTA (Islands On The Air) update.  There are some choice DX locales here, including Bere Island, Unden Island, the Scilly Islands, Isla Grande Panama, and Siladen Island.  It's time to adjust the old Double Extended Zepp and hunt for some enjoyable contacts.  Aloha de Russ (KH6JRM).

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Propagation de K7RA | Southgate Amateur Radio News

Nice numbers this week, with average daily sunspot numbers rising from 118.4 (during May 1 to 7) to 142.4 in the past reporting week, May 8 to 14.
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According to ARRL propagation guru K7RA, solar conditions should be good for the ARRL Field Day preparedness exercise on 28/29 June 2014. K7RA sees the solar flux rising from 115 on 09 June to 135 on 28/29 June.  The Planetary Index is favorable "at a nice stable 5 from 19 June forward."  Aloha de Russ (KH6JRM).

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Audio activated switch VOX, PTT controller PMR HAM Amateur radio Arduino RTL SDR

Audio activated switch VOX, PTT controller PMR HAM Amateur radio Arduino RTL SDR | KH6JRM's Amateur Radio Blog | Scoop.it
in Consumer Electronics, Radio Communication, Parts & Accessories (Audio activated switch VOX, PTT controller PMR HAM Amateur radio Arduino RTL SDR http://t.co/O7pwWFruW6
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This could be useful in the shack.  Price seems reasonable.  As with any internet purchase, check out the item and the reputation of the seller before you buy.  Aloha de Russ (KH6JRM).

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CQ Announces 2014 Hall of Fame Inductees - ARRL

CQ Announces 2014 Hall of Fame Inductees - ARRL | KH6JRM's Amateur Radio Blog | Scoop.it
CQ Announces 2014 Hall of Fame Inductees ARRL The CQ Amateur Radio Hall of Fame honors individuals, whether licensed or not, who have made significant contributions to Amateur Radio as well as radio amateurs who have made significant contributions...
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Here are the  2014 Hall of Fame inductees to the "CQ" Amateur Radio Hall of Fame..  Most of these amateur radio pioneers and technical experts are fairly well known.  These hams have done much to help us "contribute to the radio art."  We are indebted to their efforts, vision, and persistence.  Aloha de Russ (KH6JRM).

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REP Ham Fair in Lisbon - May 24, 2014

The R.E.P. is organizing an Exposition Ham Fair in Costa da Caparica, Lisbon (Amateur Radio - REP Ham Fair in Lisbon - May 24, 2014: The R.E.P. is organizing an Exposition ...
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Amateur radio operators passing through Portugal this Saturday (24 May 2014) are invited to stop by the REP Exposition Ham Fair at Costa da Caparica in Lisbon.  This is one of the biggest ham radio gatherings in Portugal.  For details, visit http://rep.pt/wp/?p=522.  Aloha de Russ (KH6JRM).

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ground_loop.pdf - File Shared from Box

ground_loop.pdf - File Shared from Box | KH6JRM's Amateur Radio Blog | Scoop.it

Via David Hall
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An excellent 86-page (pdf) tutorial on power distribution systems and the role of proper grounding of audio and electrical equipment.  Amateur radio operators will find many useful techniques on preventing group loops and other grounding issues.  I will be adding this pdf to my technical library.  Thanks to reporter David Hall for the lead.  Aloha de Russ (KH6JRM).

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Update on Transmitters

Update on Transmitters | KH6JRM's Amateur Radio Blog | Scoop.it
The technology is tried-and-true but smaller size can handle more power than ever before.

Via David Hall
Russ Roberts's insight:

Thanks to reproter David Hall for bringing this update to my attention.  This article will appeal to those of us who were broadcast engineers sometime in our distant past.  Professional Engineer Doug Irwin gives us an appraisal of the current crop of broadcast transmitters available to station owners and engineers.  Included in this summary are transmitters from Harris, Nautel, BE, and more.  Excellent review of specs and capabilities.  Back in the 1970s and 1980s, I was responsible for maintaining an old Collins 20-E 5kw AM broadcast transmitter...quite a lovely beast with its grey and chrome cabinet, rows of meters, the glowing 4X400 drivers, and the pair of 3CX2500 ceramic triodes feeding an old navy tower in the tidepools of Keaukaha, Hawaii Island.  Those were the days.  These modern rigs are quite sophisticated, more energy efficient, and have redundant power modules in case an amplifier dies.  I sort of miss the old 20-E.  It was a work of art.  Aloha de Russ (KH6JRM).

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The Real Ham Radio | VE3HG

The Real Ham Radio | VE3HG | KH6JRM's Amateur Radio Blog | Scoop.it
Here it is! My newest rig from Dayton! No it's not a Flex 6300 but that's on the list; It's a NorCal 20 putting out a staggering 5 watts and I just worked Z35G with 579 (I'm sure he was being nice.) and 5nn from me (which is all I ...
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Nice review of the NorCal 20 QRP rig by VE3HG.  The NorCal 20  is one of the finer rigs available to the QRP enthusiast.  His contact with Z35G must have been exciting!  Oh, yes, I would like to have the Flex 6300, but the ole budget is a bit stretched at this time.  I'm to old to believe in Santa Claus...Aloha de Russ (KH6JRM).

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Amateur Radio Volunteers Assist Rescue Operations in Balkans Flooding

Amateur Radio Volunteers Assist Rescue Operations in Balkans Flooding | KH6JRM's Amateur Radio Blog | Scoop.it
The American Radio Relay League (ARRL) is the national association for amateur radio, connecting hams around the U.S. with news, information and resources.
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According to ARRL, CNN, and the Serbian Embassy in Washington, D.C.,  amateur radio operators in Serbia are "putting in long hours supporting rescue operation in the wake of the unprecedented flooding in the Balkans."  Serbian officials say this is the worst flooding in more than 100 years.  CNN adds that amateur radio operators in Croatia and Bosnia-Herzogovina are also helping with the rescue operations.  An operational center has been opened in Belgrade to coordinate communications and rescue efforts. Aloha de Russ (KH6JRM).

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Connecticut Ham Uses Radio to Help Rescue Young Canoeist

Connecticut Ham Uses Radio to Help Rescue Young Canoeist | KH6JRM's Amateur Radio Blog | Scoop.it
The American Radio Relay League (ARRL) is the national association for amateur radio, connecting hams around the U.S. with news, information and resources.
Russ Roberts's insight:

You never know when that HT you have strapped to your belt will come in handy.  On 04 May 2014, amateur radio operator Keith Mutch (KB1RBI) used his HT to notify the U.S. Coast Guard of a girl and dog in distress in rough water.   Thanks to Mutch and his HT, the Coast Guard diverted a passenger ferry to rescue the girl after her canoe capsized in rough water and high winds.  The dog swam to shore, where Mutch reunited the girl with her pet.  Aloha de Russ (KH6JRM).

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It's about eliminating the last shred of competition

 

“For the amount of money and debt AT&T and Comcast are collectively shelling out for their respective mega-deals, they could deploy super-fast gigabit-fiber broadband service to every single home in America. But these companies don’t care about providing better services or even connecting more Americans. It's about eliminating the last shred of competition in a communications sector that's already dominated by too few players.”


Via David Hall
Russ Roberts's insight:

Interesting viewpoint from reporter David Hill.  I tend to agree with Hall on this one.  Once the large communications conglomerates unite, service will suffer, employees will be "retired", rates will increase, and control over the distribution of information will be complete.  I'm reminded of the cult TV classic of the late 1980s--"Max Headroom"--starring UK actress Amanda Pays.  You can even make reference to George Orwell's "1984" or to the film "Network" with Peter Finch.  With the FCC supporting a two-tier internet information highway, many of us won't be able to afford the new gigabit-fiber optic broadband services that will be offered.  Many of us will have to be satisfied with slower systems and more frequent internet outages.  After all, the issues are clear: eliminate competition, control prices and the workforce, filter what information is available, and work for the highest bidder.  It's all so neat and tidy.  Aloha de Russ (KH6JRM).

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TX5K DXpedition Wins DxCoffee/DX University “Best Communication Award”

DxCoffee and DX University have announced that the TX5K DXpedition to Clipperton Island will receive their 2013 Best Communication Award. The two groups partnered to sponsor the award.
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Congratulations to the TX5K DXpedition team to Clipperton Island.  The team ran a well-disciplined operation and gave out many contacts.  Aloha de Russ (KH6JRM).

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Practical Use: Circulators and Isolators

Practical Use: Circulators and Isolators | KH6JRM's Amateur Radio Blog | Scoop.it
These two devices, related in function and form, are indispensible when working with RF.

Via David Hall
Russ Roberts's insight:

Thanks to reporter David Hall for this article.  The Practical Use of Circulators and Isolators is a basic tutorial on these vital transmitter components from Doug Irwin, CPBE, DRB, and AMD.  According to Irwin, isolators and circulators are integral parts of HD radio transmitters using the VHF/UHF spectrum.  Engineers use isolators to control intermodulation products.  Junction circulators "direct the signal flow clockwise or counterclockwise, depending on the polarization of the magnetic field."    A good technical tip for the day. Aloha de Russ (KH6JRM).

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Nevada Governor proclaims June as Nevada Amateur Radio Month

Nevada Governor Brian Sandoval has named June as Nevada Amateur Radio Month (Nevada Governor proclaims June as Nevada Amateur Radio Month http://t.co/VGXBmBFwQ2 #hamradio #hamr)...
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Thanks to John Bigley, Assistant Director-Pacific Division, for this announcement.  In his proclamation, Nevada Governor Brian Sandoval praised Nevada's 6,800 licensed amateur radio operators "for their commitment in providing voluntary communications services to Nevada and the world."  A copy of this document should be posted at every field day site in Nevada.  Aloha de Russ (KH6JRM).

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HAM Video Premieres on the Space Station

HAM Video Premieres on the Space Station | KH6JRM's Amateur Radio Blog | Scoop.it
Astronauts on the International Space Station can now talk with people on Earth with video using simple transmitters. (Hey amateur radio enthusiasts, we now have #HAM TV on space station!
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The new Ham TV station on board the International Space Station (ISS) became operational on 12 April 2014.  NASA astronaut Mike Hopkins had the honor of being the "first to commission the video and broadcast over Ham TV."  The new amateur radio television station will add a "visual dimension" to ARISS programs. Schoolchildren will be able to see and hear astrounauts in with simple equipment.  Great program for the students!  Aloha de Russ (KH6JRM).

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Audio Meters are Misleading

Audio Notes: Tim Carroll

DTV and 'The Annoyingly Loud Commercial Problem'

Last time we investigated how audio metadata is created and distributed, and what happens if the values are wrong or missing. We also discovered that the Dolby Digital (AC-3) system can potentially be "tricked" into allowing overly loud program material to be delivered to consumers. This led us into the topic for this issue: Loudness, or as it is more commonly known: "the annoyingly loud commercial problem." This is such an important issue that back in the 1960s the FCC studied it and made it illegal to broadcast irritatingly loud commercials (unfortunately, they made no such rules for irritating content). Have things gotten better? What will happen with DTV? Let's start by figuring out how to measure this often disagreed-upon-thing called loudness.

 

COMMON METERS

 

VU, or Voltage Unit meters, and PPM, or Peak Program Meters, are both very common measuring devices found on modern audio equipment. The VU meter traces back to the 1930s, well before most of us made that fateful choice of a career in broadcasting. PPM has also been around for quite some time and although more popular in Europe, has seen its use increase worldwide since the introduction of digital technologies.

Although they are both common and useful, both these devices were designed to measure and display voltages and do not give an accurate measurement of program loudness. The reason for this is quite simple: Loudness is a subjective quantity, and VU and PPM meters are objective voltage-measuring devices. This means that if two programs are measured with a VU or PPM meter (or even a combination of the two) and adjusted for equal readings, it is quite likely that they will still differ in perceived loudness. What we need is a way to accurately describe a quantity that can be perceived but not directly measured.

 

SUBJECTIVE MEASUREMENT METHODS

 

Back in the 1960's, Emil Torick, Bronwyn Jones, and colleagues at CBS Laboratories developed a loudness meter modeled after human hearing. Simply put, the meter divides the audio into seven bands, weights the gain of each band to match the so-called equal loudness curve of the ear, averages each band with a given time constant, sums the averages, then averages the total again with a time constant about 13 times longer than the first. The resulting signal is applied to a display with an instantaneous response. Okay, maybe not so simple, but the CBS meter was found to agree with listeners within 2 dB (although listeners disagreed among themselves by as much as 4 dB when judging the loudness of a given piece of audio).

This was one of the first truly successful attempts to measure loudness accurately and helped solve the problem. Unfortunately CBS Laboratories does not exist anymore and there are very few CBS loudness meters in existence today, so the use of this measurement technique has become rare. One exception is that a few broadcast audio processor manufacturers use an algorithm developed from the CBS loudness meter to combat the "loud ad" problem. When the algorithm detects that audio would sound too loud to a listener, it causes gain reduction thereby eliminating the problem.

 

Another method is called Equivalent Loudness, or Leq(A), where the "A" represents A-weighting. Leq(A) can be defined as: "The level of a constant sound, which in a given time period has the same energy as a time-varying sound." Leq(A) is the method that is specified by the ATSC for measuring dialnorm, and until recently relied on the use of some rather complex meters, conversion tables and a bunch of luck to get the correct result. This complexity did not lend itself well to solving loudness problems.

Thankfully, Dolby Laboratories recognized that a simpler method was necessary if the proper setting of dialnorm was ever to be achieved and developed the LM-100, which was shown at NAB2002. The device displays both the Leq(A) value and the corresponding dialnorm value and happily requires no conversion charts!

 

CAUSES OF LOUDNESS PROBLEMS

 

The major cause of loudness problems then is probably the use of the wrong meter. As we discussed earlier, VU and PPM meters only measure voltage and because of their very nature cannot be used to adjust program loudness; however, most facilities still rely on them to adjust both the level and the loudness of programs. This inevitably leads to content that looks fine on the meters but can cause viewer complaints when broadcast.

Another cause of loudness problems is programming with mismatched dynamic ranges. Programs that have a large variation between the softest and loudest sounds (i.e., have a large dynamic range) are difficult to match to other programs. For modern digital media, dynamic range can theoretically be in excess of 90 to 100 dB. If you wish to integrate a program with such a wide dynamic range, what section do you measure when trying to gauge loudness? Do you line up the crickets of one movie with the cannon shots of another? This is probably not a good idea and will give predictable (and irritating) results. The general answer would be to measure and line up the "anchors" aka the dialogue of both films, assuming of course there is dialogue.

Modern commercials, on the other hand, intentionally have little dynamic range in an effort to keep the dialogue or the message as clear and present as possible - maybe sometimes too clear and too present! Restricting dynamic range lowers the peak-to-average ratio of the audio and allows a given program to have increased loudness without causing overloads like you would have if you adjusted for crickets and got cannons. The only drawback to restricting dynamic range is that, well, the dynamic range is restricted, and this tends to remove some of the fun of cannon shots.

 

SOLUTIONS FOR LOUDNESS PROBLEMS

 

There are several options for solving loudness problems, and they range from measuring and adjusting to dynamic range control. With meters such as the LM-100, it is possible to check all programming that will be carried via Dolby Digital (AC-3) and adjust its dialnorm value in the audio metadata. This will allow the proper attenuation to be applied in the consumer decoder, and all programs will be reproduced with equal dialogue loudness. However, as we discussed above, programs that have a large dynamic range may be problematic for this method.

Another approach is to use an audio dynamic range processor to narrow the range between the softest and loudest sounds. Doing so provides for much easier loudness matching of one program to the next, and in fact one broadcast signal to the next. These devices from Orban and others are commonly found in analog broadcast facilities but have not yet made their way into DTV facilities. This is partly due to the built-in dynamic range control (DRC) system contained within Dolby Digital (AC-3) and partly due to the need to deal with up to 5.1 channels of audio. As I found out in some late-night experiments, it is not possible to just use three two-channel processors as it causes strange things to happen to the soundfield as well as making for some very bad downmixes. Also, remember that unlike DRC where viewers have the choice of ignoring the dynamic range control metadata and hearing full dynamics, once the dynamic range of the audio has been reduced by an audio processor prior to the Dolby Digital (AC-3) encoder, it cannot be undone.

In summary, loudness problems have plagued television for many years and will surely cause some problems with DTV as well. It would seem that the Dolby Digital (AC-3) system alone might not be enough, but severe restriction of dynamic range is certainly not the answer. I believe the best answer is a combination of carefully measuring program loudness using a meter based on Leq(A), setting dialnorm properly if possible, and judicious use of dynamic range processors that are designed to work in combination with audio metadata. These devices should pay attention to the audio and the metadata and process only when they need to, such as when dialnorm is mistakenly or purposefully set wrong. This will keep viewers happy, keep the FCC happy, and preserve the benefits of DRC for those of us who just cannot get enough of those full-throttle cannon shots.

Next time we will look at the second-largest complaint with television audio, namely audio/video synchronization better known as lip-sync. We will look at some of the causes, but also discuss some new and inexpensive tools that should make lip-sync error improve dramatically.

Thanks for your continued support and the steady flow of e-mails. I would like to thank Jeffrey Riedmiller of Dolby Laboratories whose expertise with loudness issues both helped with this article and thankfully led the development of the LM-100.

 

Tim Carroll is a consultant based in New York City. He is currently the chairman of the audio section of the Systems Evaluation Working Group of the ATSC, and chairs the IEEE G.2.1.2 Audio Measurement subcommittee. In his copious spare time, he enjoys mowing his lawn and answering e-mail sent to him at: tjcarroll@ieee.org. 


Via David Hall
Russ Roberts's insight:

A nicely constructed tutorial on loudness problems found in commercial radio and television broadcasting from New York City-based consultant Tom Carroll.  Carroll covers a variety of topics, including causes and solutions to audio problems and the limitations of various audio measuring devices.  Excellent material.  Aloha de Russ (KH6JRM).

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