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Published by: Larry Bloomfield & Jim Mendrala

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August 7, 2000

 Tech Note - 060


Sharing experiences, knowledge, observations or anything relating to Digital Television, Digital Cinema, etc. with fellow engineers and readers is our purpose. Our mission statement and other relative information is now posted on our new website:  We increased our subscribers by over 100 in the past month along to now over 810 subscribers and growing.  Thanks to our regulars and welcome to the new folks.  This is YOUR forum! 

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Reader comments:

From: Andy Toms

RE: Comments on the Web site.

I came across your web site during my efforts to gain some insight into the transition to DTV/HDTV. It is interesting to see some opinions that do not necessarily just pander to the desires of equipment manufacturers, as is so common in most of the trade magazines.

Point to Ponder:  Poor quality unchallenging programming remains so, whatever the definition, digital or analog.

Andy Toms, Chief Engineer -- Studio Post, Edmonton, Alberta, Canada


From: Jim Waschura

Re: Tech-Notes -- 059

Thank you to John Luff of STI Digital for his remarks concerning committee work.  I have participated in SMPTE engineering committee meetings for a few years now and no one asked me for my secret card before I could participate.  I just volunteered to work for the best interest of the community, and to respect the practice of keeping intermediate work confidential among the participants.  There's absolutely nothing "back room" about it; anyone who's willing to work can participate.  In particular, the committee I work on has published specific questionnaires and requests for information in trade journals to obtain industry input (and received very little response, I might add).

Most importantly, I hope the acidulous level of correspondence can be squelched soon.  I doubt that it will be productive.

Jim Waschura, SyntheSys Research Inc.


John A. Luff Synergistic Technologies, Inc.

(Ed Note:  The following are excerpts from an e-mail we received in response to Tech-Notes 59.  We were asked not to publish it.  In deference to the author, we have only shared part of this e-mail as the author, John Luff makes some good points that need to be mentioned.  Since it is my opinions – Larry Bloomfield – with whom he disagrees, I will take the liberty of making comment in italics, surrounded by [ ]’s through those parts we have chosen to print.  In many respects, we are not that far off.)

I see (this) as exceedingly complex and intertwined.  [Agreed!]

ATSC does at times act in ways that seem to those who are not involved to be without adequate explanations. It is important to note that the standards work is done by individuals who labor long and hard to solve the problems they are handed, in the most appropriate manner they can. [Agreed!  And they are to be commended for their Herculean efforts.]

The fact that DVB seems to have "gotten it right" in the opinion of some in our industry is in part because they started later and had the benefit of close coordination with the research labs in Europe who were developing COFDM and evangelizing its capabilities on both sides of the Atlantic. Unfortunately for the US market they were a little too late in developing a demonstrable system. [I do not believe it is ever too late to look at better technology.  If that were the case, we might still be driving teams of horses instead of cars.]

I find it particularly interesting that broadcasters in general showed little interest in the entire DTV proceeding until it came time to implement. [This is a very true statement!  Where were the broadcasters when all this was being put together?  They certainly have always had a vested interest, but seem to have taken a rather cavalier attitude.]    Very few spent any time in the ACATS or ATSC processes. It is regrettable that the best science of 5 years ago is now proven to be at least suspect, but it was not done in the dark, or by a rump committee that wanted to somehow promulgate a travesty on the American consumer. [I don’t believe any right-think person believes it was.  It’s just that something better is available now and the old should give way to the new. The patches and band-aids don’t seem to be working very well.] 

You seem to be crying out that you want to know what is being said and done...seems to me that is not prior restraint, but lack of personal knowledge.  [Agreed it is lack of knowledge due to lack of disseminated information.  If ATSC, or any other standards making body for that matter, put out progress reports saying what they were doing and were they were in their deliberations, the air of suspicion would certainly be dissipated.]

The ATSC's privacy statement is no different that a Non-Disclosure Agreement, many of which I suspect you have signed, as have I, over the years when working closely with manufacturers. [I disagree with this.  An NDA is to protect a company’s proprietary interest and their developmental efforts.  It is not an instrument to keep the public from knowing about standards that will impact their lives.]  ATSC manufactures intellectual property, which is in the public domain when finished. [It should be from start to finish.]  I cannot see why it is not within the legitimate rights of ATSC to manage the dissemination of information about things that MAY be done in the future any differently that it is with the FCC, or for that matter GM or AOL.  [The FCC had better keep things public.  GM and AOL are private concerns and unless they are developing standards for all of us to abide by, I don’t care what they come up with.]

…… could contact the FCC and ask what they are doing in the OET about the problems. I think you will find they have already said that VSB progress is acceptable to them (loose interpretation by myself, and poor science by them), but they are doing their own comparison field tests now, as well as is MSTV.  [If you read these Tech-Note regularly, you will see where we have said that the FCC is today a mere shell of a once well respected engineering organization that has been so politicized that it bears little resemblance of what it once was when we could depend on them to find the best ways, out in the open, for broadcast industry standards of technology.]

It is my opinion that stirring the public caldron will only make the introduction of DTV slower. I suspect you do not share that opinion. [Perhaps you’re correct, but I’d rather stir the public caldron than be saddled with a standard that is second place.  I never want to see us take second place in anything, especially technical standards.]

Lastly, you seem to be afraid of what is being done TO broadcasting by parties who you seem to feel are not involved in the craft.  If you attended even one meeting you would find that to be untrue. [Not so.  We can do a fine job of shooting ourselves in the foot without any help from outside the industry.]  

Why don't you come into the tent for just a minute and see what is in there. [I accept!] You would be required not to report to your newsletter the contents of but one short meeting, the contents of which would no doubt end up on (an internet) forum within hours anyway without your complicity. [I cannot, nor will I ever agree to keep confidential any standards setting sessions that affect the entire industry and possibly the world.  These are not priority issues!] You may well find that you can make a contribution if you try. Participation is available by dial in [Send me the numbers.] so long as you agree to the privacy guidelines. [I’ve addressed that and I will not play politics!]  I think you would find it worth your time, and of service more to the industry than complaining without knowledge of what you are complaining about. [I would be more than happy to contribute my time and efforts, but I will not join in with anyone who must make public standards behind closed doors. And by the way, Jim Mendrala doesn’t agree with me on this, but understands where I’m coming from.  Do you?]


From: Dick Hobbs

Re: Tech-Notes -- 059

I thoroughly approve of your dismissal of John Luff's arguments. It is quite clear that, with very few exceptions, groupings of learned bodies have produced deeply flawed compromises rather than best engineering practice. As the English proverb has it, the camel is a horse designed by a committee.

Without wishing to tell you folks on the left hand side of the Atlantic what to do, I cannot help thinking that, if there was rather more public scrutiny of the FCC's workings, then perhaps it would have taken more notice of the digital television experiences of us on the right hand side of the Atlantic.


Dick Hobbs  (writer and commentator on the application of broadcasting technology as it relates to the viewing experience.)


Subject: DTV Multimeter

From: Roy Trumbull - ENG

I've been kidding for several years that for DTV transmission we need the equivalent of the old Simpson 260 multimeter to do basic testing. I've looked at several systems that do detailed analysis of the digital signal.  But the sorts of information they collect would be what a system designer or software developer needs. I just want to know if the system is alive and has normal vital signs.

At a recent SMPTE meeting, Joseph Nigro, the sales manager of Triveni demonstrated a tool they've developed that runs on a laptop with a receiver card. It captures a sample of the signal and then displays the packets in multiple colors. TV services are in different shades of green, audio packets are red, null packets are black, PSIP packets are another color, etc.. You can click on a packet and find out what's in it.

For example, clicking on an audio packet gives a red waveform display that can be expanded. The normal profile is stairsteps of data filling a buffer and then a steep falling edge as the buffer unloads. We tuned in a station that's acquired a certain fame for having a faulty encoder. The profile was very different. There were fewer steps, a long plateau, and then a drop.  The display shows where your audio is relative to the model of receiver buffers so you can avoid causing underflow and overflow problems. Similar displays profile video.

In short, I felt that this product would give you what you need to know. I don't have a model number or a price, but I want one.

Roy Trumbull


Subject: Microwave Standards

From: Bill Ruck

This is something that all of you that are in the 1.0 V P-P world may have an interest in.

The TIA/EIA has proposed to reaffirm EIA Standard RS-250-B, Electrical performance Standards for Television Relay Facilities without changes or updates.  This version of the standard was adopted September 1976.

The standard was approved for reaffirmation by the TIA TR-14.10 Subcommittee on Electrical Performance Standards for Steel Antenna Towers & Antenna Supporting Structures.  I've been told that they claim there was no interest in modifying or updating the standard by the broadcast industry.

I would expect that there might have been a few changes in TV since then.

If you are interested in participating in the standard process, contact:

Billie Zidek-Conner -- Standards Secretariat

Telecommunications Industry Assiciation (TIA)

2500 Wilson Blvd., Suite 300

Arlington, VA  22201-3834


The process is open to all interested parties.

Bill Ruck, Chair -- Northern California Frequency Coordinating Committee


Subject: CBS Field Sequential Color System

By: Jim Mendrala

The CBS field sequential color system in its simplest form consisted of a rotating color wheel of red, blue, and green filter segments in front of a monochrome camera, feeding a black and white CRT receiver viewed through a second rotating color wheel. The two wheels were kept in phase synchronization, such that successive television fields were viewed using identical color primary filters to that at the camera. To overcome flicker, the field rate was increased 60 to 144 fields per second resulting in 24 complete color frames per second. To compensate for the increased field rate within the standard 6-MHz channel, the lines per frame were reduced from 525 to 405. A 29,160-Hz line rate resulted. This led to the basic incompatibility of the CBS system: no standard monochrome receiver could present an intelligible picture during the color telecasts.

CBS had first broadcast its Field Sequential Color System as early as

August 28, 1940. Their 1949 Color System was the third field sequential approach to be proposed to the FCC for adoption. They had suggested that their field sequential standards be adopted in 1941 and 1946. At those earlier times, with few black and white receivers in the hands of the public, the adoption of the CBS system might have been feasible.

It is interesting to note that today a 24p or 30p image can be transmitted and displayed at 144 or 180 fields per second using Colorlink's ( ColorSwitch.  This is what we will be seeing in the near future on some of the new displays that will be coming out shortly. (  Displaytech seems to be a leader in this area so far. They were demonstrating field sequential at 180 fields per second and 30 frames at the SID held at Long Beach, California back in May.


Subj:  Stirring the 8-VSB – COFDM Pot Again.

By:  Larry Bloomfield

Hardly an issue in history broadcast has taken on such religions connotations, as has the debate over 8-VSB and COFDM.  Proponents of each appear to be fighting with their dying breaths to either keep their ground or at least gain equality, as the case may be.

When it was heard that House Telecommunications Subcommittee Chairman Billy Tauzin (R-La.) invited Sinclair to do a live, over-the-air demonstration of 8VSB versus COFDM--competing digital TV modulation technologies--at a hearing on digital TV scheduled for this month, it was time to call Ken Johnson, the congressman’s spokesperson.

Johnson, said: "Obviously there is a great deal of concern here on Capitol Hill about how consumers may be impacted during the transition to digital.”  As a result, Congressman Tauzin held a public hearing on DTV standards, and the transition to digital, not ten days ago. 

There is little question that the transition to digital has met with a multiplicity of unforeseen obstacles; the robustness of 8VSB as compared with other modulation techniques such as COFDM is only one of the more visible.  “We are going to invite engineers and broadcasters who support both DTV standards (8VSB and COFDM) to testify,” Johnson said before the hearings. 

Now a matter history, it appears that Congressman Tauzin wants HDTV and a band-aid for the questionable 8-VSB.  It came across to me as my son, when speaking of the misdeeds of my 2-year-old grandson, “so he’ll get over it.”  My question is, in both cases, how do we live with the situation in the mean time and what happens if he doesn’t get over it?

Prior to the hearings, Congressman Tauzin met recently with David Smith, President of Sinclair Broadcast Group (SBG).  Smith and the engineers from the SBG have been vociferous proponents of COFDM as an alternative to 8VSB, submitting a failed petition representing over 300 full-power broadcast stations to the FCC on the very issue.  Apparently Smith found a receptive ear with the right Congressman.  Johnson continues, “and he (Smith) made a compelling argument that current standard may preclude millions of Americans from getting effective digital signals.” 

“Obviously that sent up a red flag,” Johnson said, repeating what the congressman said: “‘it’s time to show me’.  So we've asked Sinclair, among others, to demonstrate what a live, over-the-air signal would looked like.  If it's true, as they say, or it's true as they claim, that many Americans will be looking at blank screens, I suspect you'll see a lot of Congressman with blank expressions on their faces at that hearing,” Johnson concluded.

There’s little question that Sinclair has fought a strong, uphill battle.  It seemed like it was all over but the shouting when the FCC summarily dismissed the Sinclair petition in February, but apparently Smith and company had one more ace up their proverbial sleeve.

In a public statement on the same subject, Johnson said:  "Even though this is a technological argument, our eyes may tell us a lot more than our ears.  That's why we want to have a public demonstration during a Congressional hearing." 

Referring to the SBG/Smith visit, Johnson said:  “They make a very compelling argument that millions of Americans may be looking at blank screens. If members are looking at blank screens, I think a lot of jaws are going to drop,” Johnson warned.

It certainly doesn’t hurt to have the Chairman of the Congressional committee that signs the FCC’s pay checks in your corner…   Now all they have to do is make their point!

But did they?  From reviewing the various testimonies given, it is difficult, at best, to determine what will become of all this.  Between the political/half-baked-scientific rhetoric, good old fashioned Washington, DC BS (I don’t mean bachelor of science either) and detracting misinformation, those who had something worthwhile to share were lucky to have been seen in the spill from the misguided spotlights.  I walked away with the idea that 8-VSB was given just one more of many chances to get its collective act together and then who knows.  If what is said: “broadcasters are simply trying to delay the transition” is true, they sure got lots of help from the congressional hearings. 

Where’s the lady?  I don’t think she’s even begun to warm up as yet, much less come to the microphone.  Remember, we still have the somewhat stalled biennial review by the FCC.   If fact cannot overcome the shortcomings of what we now have, we may have gotten to the point of diminishing returns when it comes to getting an alternate technology for a modulation system. 

Through all the skull dungaree and Washingtonian intrigue, we will one day wake up to find that we are not the only ones on this planet!  World standards are a must or we will be condemned to relive our history to the tune of many pieces of latnum.  I’ll never understand why all that good hard earned, but wasted money never falls into my coffers.  I’m somewhat glad it doesn’t, because I like being able to sleep at nights with both eyes shut.



Subject:  History? I've got a few tales

From: Robert Lund, Avenir Designs 

It's good to see someone who appreciates the legacy of the technical development of this medium, which engulfs modern life. Plans for a web site go round in my head, but daily life has a way of putting it off to some hopefully near future date. I can't write my contribution to history right here on a Sat. morning, but lemme give you an idea of my connection with telecine et al.

When I left Bell Labs to work at Teletronics in 1972, Armando Belmares-Sarabia and Robert Lieberman did telecine transfers using an “automated” color correction system custom-built. Metal tabs were clipped to the film, which triggered the system during transfers to kick in the next sequential set of corrections. Color parameters were stored in one of 9 potentiometer banks, which were selected by thumbwheel switches. You get the idea, a totally analog hardware solution. I got familiar with PDP-11 minicomputers there and then, the basis of the early CMX systems I was charged with maintaining and upgrading. So we designed and built a computerized system to replace the old pot-based suite, based around a PDP-11. Designed in concert with the end user, Joe Bond, it was tailored to his needs, and stored data in a table in core memory. It was a big moneymaking hit, and we built two more systems for the facility. Sarabia's attorney got the thing through the patent office (in spite of the fact that young, naïve me maintained that it was "just a project, not a true invention"), and a patent was granted in 1978, shared by Armand, Stan Chayka, and myself young technician. Armando and Stanley took the patent and formed their own company, eventually suing many manufacturers AND customers during the 1980s as though he had the patent on computer-assisted telecine color correction.  Testifying at depositions against my old boss on behalf of a consortium of manufacturers/defendants in the 1980s was extremely interesting and rewarding.

If you'd like to know more about this aspect of telecine history, lemme know, and I can dig into my archives and provide many more details and anecdotes. Great thing you're doing!

Robert Lund

“So many good ones, and so many bad ones; that's what you get for trying."  Dutch Schultz, last words

(Ed Note:  There’s no way telecine will go away in digital television or HDTV.  The fact of the matter is that most all HDTV material on the air weekly, now, originates on film and is transferred to HDTV by one of the Colorists from the telecine/post production part of our industry.)


Subj:  Electrifying ENG Experiences

By:  Larry Bloomfield

It was mid-Monday morning, May 22, 2000, that the news wires began to buzz with a story about a news incident that occurred in Southern California.  It was the kind of story that none of us in the broadcast industry like to hear: one of our own was hurt while covering a news story! 

It was a typical Monday morning.  Assignment editors were sending out newscrews and minivans to begin putting together the stories that would appear on their stations daily news fair.  At about 9:40 that Monday morning, photographer/technician Heather MacKenzie and reporter Adrienne Alpert, arrived to cover a Los Angeles police news conference in Hollywood on Santa Monica Boulevard where they would join other news crews to report on a story about child car seat safety. The assignment itself took a backseat to the very unfortunate incident that was about to occurred.

As assignment editors across the country became aware that something “hot” was unfolding, they called up Telstar Six, One Delta and it was there that the chilling story unfolded before their very eyes, bring a halt the beehive of activities associated in their respective newsrooms while they mused:  “My God! That could have been us!”  Unsteady cameras showed what had happened and it was not what they had been sent to cover, but rather what had happened to a news van and members of their crew. 

A KABC-TV news van microwave dish had brushed a power line in Hollywood, burning reporter Adrienne Alpert over 25% of her body. Adrienne Alpert is a well-respected veteran of over two decades, who has covered stories from nearly every venue in both the San Diego and Los Angeles markets. 

After arriving to cover the story, they apparently agreed that the location they had first chosen to park was directly under the power lines, so they moved to a location a few feet away. Nothing particularly unusual about that, but the location chosen had a pronounced slope downward toward the street, where they had just come from.  Since the van sat on a slope, the mast was listing from vertical. Eyewitnesses say that the driver side of the van was within a foot or two of being directly underneath a 34,500-volt service. Above those lines were perhaps a dozen other lines carrying even higher voltage.

Inside the truck MacKenzie called in to begin transmitting and steering the dish to a relay site. Witnesses, including a couple of mechanics working near where the two had parked, said they began yelling at the two in the van from outside to “stop the raising mast.” A crew across the street from KRCA, channel 62 started videotaping the mast as it brushed the wires, while they too were yelling and waving.

Alpert decided to get out of the van's passenger side doors.  As Alpert stepped out of the van, that completed the circuit from the 34,500-volt line, arcing through the top of the parabolic dish to its inner reflective mesh, its mount, down the aluminum mast, through the van body and its door handle, through Alpert’s left hand, through her body and out her right foot.

The van was parked so near the building that the door apparently struck the wall. A nearby drainpipe that appeared to be an air conditioner’s condensate (water) runoff was seen in several after shots with a large char mark where the pipe enters the steel mesh-filled stucco wall. The pavement was wet where the water had been draining near the front of the van. Whether Alpert stepped on wet ground is not clear. It is believed that when the door hit the wall, the main explosion apparently occurred.

Bystanders wanted to assist, but weren't sure whether they were clear of electrocution danger yet. The mast came down from the wires rapidly; the seals had failed.  It wasn’t clear whether Alpert’s windpipes had been burned or her diaphragm had been paralyzed, but she had trouble breathing and asked for help.

The closed circuit feed showed horrible burns on Alpert’s limbs where she had suffered fourth-degree burns.  Doctors have performed vascular surgery to remove blood. The result of this injury has caused Alpert to go through amputations of the left forearm and right leg below the knee and had required assistance from a respirator.  There is no question that Alpert is glad that was the extent of her injuries and just happy to be alive. 

MacKenzie, the van’s driver and technician, was not injured.

Fearing lawsuits and not wanting to spawn misinformation, many insiders have been reluctant to discuss the specifics of the accident.  Nonetheless in speaking to folks "on the inside" at KABC-TV, there remain a lot of unanswered questions on her accident, and multiple versions of the details of what happened, and why. 

Despite that this incident occurred in Southern California, it could have, and has happened, all to frequently else were.  Peter MacNaughton a 30-year-old photographer/technician on assignment from KGAN-TV in Cedar Rapids, Iowa, while preparing for a live news report at Squaw Creek Park in Marion, was shocked and burned just five days later on May 27th, as he was raising the mast on a microwave news van.  The mast came in contact with an overhead power line that was carrying 115,000 volts of electricity.  MacNaughton suffered burns over 25% of his body. 

There is little doubt that ENG crews all over the country have recounted these and other events in their minds. Let he who is without sin cast the first stone.  One’s first reaction maybe: what was she THINKING about to have raised that mast into that web of electrical lines? This most likely would be followed by a second reaction: been there; (almost) done that!

While the Southern California press focused on the ENG antenna contacting a 34,500-volt line, engineers know that two points of contact are necessary to complete a circuit.  There are still several unanswered questions:  Was Alpert "blown out of the van" according to some press accounts, or did she deliberately bail out because of smoke and/or fear of an explosion?  Was there in fact an explosion as some press accounts reported, or simply arcing?  Exactly what did Alpert (and the two other injured individuals) touch to draw electrical current?  It is tempting to say that Alpert stepped out of an electrified van thereby completing a circuit to ground, but the details may be more complex.

While some vans have the mast deployment controls inside, others require the operator to stand outside.  The older, homemade vans from several years back, and before, had controls inside the working area at the top of the rack, so that an operator could engage the mast without ever getting out of the van to look for obstructions.  No roof window, not even a floodlight was mounted at the bottom.  Newer vans, however, have the controls inside the rear door and a floodlight shining up which can't be extinguished.  An operator must get out of the van, open the door, reach inside, and engage the air valve upward.  It was not clear which type KABC-TV van was, but the incident occurred on a clear day in the middle of the morning. 

Like locking the barn after the horse has runaway, it only took two days for unions representing broadcasters and camera crews to call for “an emergency meeting” to devise uniform safety standards for newsgathering in the field. Union representatives said they were hopeful to meet with stations no later than May 30 to begin establishing safety guidelines. "We want all (stations) to follow a standard," said Gena Stinnett, president of National Association Of Broadcast Employees and Technicians-Communication Workers of America (NABET/CWA) Los Angeles area, Local 57. "No station should try to beat another station to a story by cutting corners on safety," Stinnett concluded.

Not to be outdone, the American Federation of Television and Radio Artists AFTRA) joined Stinnett's union in calling for safety guidelines. According to Gerry Daley, AFTRA local spokesperson, there are no “adopted” safety standards for this kind of thing and the Occupational Safety and Health Administration (OSHA) has no such guidelines for the broadcast media.  Our research (Broadcast Engineering) found well-documented guidelines on this very topic.  

The bottom line is, there are a few hints as to the mechanics of the accident, but prudence dictates that we await the authoritative reports.  Once the true facts are known, accident prevention programs can be implemented and fine-tuned.  This does not belie the old adage; an ounce of prevention is worth a pound of cure.  It is incumbent on station managers and Engineering Managers to make certain that anyone who operates an ENG van, truck, or mobile studio, that all their staffs have been fully trained, educated, and understand fully the dangers involved where overhead power lines, etc. are concerned.  This is a management must and should be documented in writing.  Refresher courses are less troublesome then attending a colleague’s funeral. 

Safety is ALWAYS the crew's responsibility, but a responsibility that must be SHARED by station management.  The crew MUST have the proper tools: Adequate SAFETY DEVICES must exist and be checked regularly.  And PROPER SAFETY TRAINING must be provided regularly too, just as it is for an airline crew.  Then and only then can the workers be responsible for doing their jobs safely.

But largely the conclusions come down to TRAINING. Hardware issues are far more limited and manageable.

Does your staff know:

1.  what happens when you park on a slope and raise a mast?

2.  trees can hide wires?

3.  how to get away from a suspected charged object?

4.  what to do when their GFI won't let their extension cord energize in a rain storm?

5.  what to do when a safety issue seems to conflict with news gathering?

6.  how to safely rescue someone who is being electrocuted?

If you have a training packette prepared, how well is it written? For example, does it say: "you should have 10 feet of clearance for every 50,000 volts on a line?" That’s meaningless! How will your staff measure the voltage of the distant line and how will they measure the distance?

Would a dedicated technician onboard prevent more accidents? Maybe. Surely, this question will be dragged into any litigation regarding the KABC-TV incident. Union shops like theirs, at one time, had a third person dedicated to set-up and driving ENG vehicles. Unfortunately, marginal safety loss has to enter into any equation regarding staff cutbacks.

Safety devices back up trained humans, and trained humans back up safety devices.  When you have both components, you have an interlocking, synergistic system that works.

It's understandable that we want to put safety measures in place right away so that these tragic accidents will not, or cannot happen again, at least in the same way.  It's for that reason that many engineers and technicians are coming up with all sorts of schemes to prevent this type of accident.  It is equally as important; before we over-engineer our professional practices and procedures we begin with some basic questions.  Is the "one-man band" ENG crew basically unsafe?  Is it unsafe sometimes, and safe on other occasions?  Who determines when it's safe and when it isn't?  There are similar concerns about transmitter engineers who work alone in rather dangerous areas.  Is there a relationship between accidents in our industry and financial cutbacks?  The picture may indeed be larger than we realize.  This will never change the fact that accidents are very sobering events, happening lightning fast with life-altering consequences.

For additional information on ENG Safety and the two incidents reported above, visit the following web pages:




From: CGC Communicator --

Larry Quick of KSDS uses a Phartronics "pressure sensor interface" to convert transmission line gas pressure into a DC voltage for remote monitoring.  The Phartronics PSI-V3 has 0.25% full-scale linearity, works with pressures in the 0 - 14.5 PSI range and outputs 0 - 4.5 VDC in proportion to the pressure.  A wall wart powers the device, which is supplied.  Cost is about $200 and Harris and RF Specialists sell the units.  The company can be reached at

What kind of handy, obscure and unique gadgets do you have around your transmitter plant?

Ron Gonsett -- CGC Communicator.


Subj: Technological Advances     --  Faster Than A Speeding Bullet!

By:  Larry Bloomfield

You had better believe it!  If what scientists are claiming, there are a few physics books that will have to be re-written.  Until now, we’ve all been told that nothing can go faster than the speed of light, but as the song from Porgy and Bess goes, “It Ain’t necessarily so!”  The implications are mind-boggling: Using current thinking, one interpretation would have light that will arrive at its destination almost before it has started its journey. In effect, leaping forward in time.

When Dr. Lijun Wang and his colleagues, of the NEC research institute in Princeton, transmitted a pulse of light towards a chamber filled with specially treated cesium gas; before the pulse had fully entered the chamber it had gone right through it and traveled a further 60ft across the laboratory. In effect the light existed in two places at once, a phenomenon that Wang explains by saying it can be explained by the wave nature of light.

Exact details of the findings remain confidential, as the test procedures have been submitted to Nature, the international scientific journal, for review prior to their possible publication.

Needless to say, this is causing quite a stir in the Physicist community.  What seems to be the key issue is that if light travels forward in time, it could possibly carry information, breaching one of the basic principles in physics - causality; the principle of relationships between cause and effect, which says that a cause must come before an effect.  This would also shoot some very big holes in Einstein’s theory of relativity which depends, in part, on the speed of light be unbreachable.   

Wang said he could not give details but confirmed: “Our light pulses did indeed travel faster than the accepted speed of light. I hope it will give us a much better understanding of the nature of light and how it behaves.”

Dr. Wang is apparently not alone.  In a paper published by physicists at the Italian National Research Council, they described how they propagated microwaves at twenty-five percent above the normal speed of light.  The group speculates that it could be possible to transmit information faster than light. 

Dr Guenter Nimtz, of Cologne University, an expert in the field, agrees. "The most likely application for this is not in time travel but in speeding up the way signals move through computer circuits," he said.

Wang's experiment is the latest and possibly the most important evidence that the physical world may not operate according to any of the accepted conventions. In the new world that modern science is beginning to perceive, sub-atomic particles can apparently exist in two places at the same time - making no distinction between space and time.

Neil Turok, professor of mathematical physics at Cambridge University, said he awaited the details with interest, but added: "I doubt this will change our view of the fundamental laws of physics."

Wang emphasized that his experiments are relevant only to light and may not apply to other physical entities. But scientists are beginning to accept that man may eventually exploit some of these characteristics for inter-stellar space travel.  Maybe some of the things we’ve seen on Star Trek are more science than fiction.



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