April 2012
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The Broadcast Electronics FW-30 automatic exciter switcher

This is a neat piece of kit, designed to save those late night/early morning call outs, which is the ultimate goal of all broadcast engineers, or at least it should be.  This seems like a really good idea, however, BE has discontinued the product line, the last manual update is from 2000.

Broadcast Electronics FW-30 exciter switcher innards

Broadcast Electronics FW-30 exciter switcher innards

A small four port coax switch is located next to the power supply transformer.  This is controlled by the circuit board.  The circuit board senses loss of excitation by detecting a forward power level below the threshold set on the board. The power sample comes from the exciter forward power remote metering terminals.  Thus, it can be used with any exciter(s) that have a remote forward power sample.

BE FW30 exciter switcher block diagram

BE FW30 exciter switcher block diagram

The idea is to use the RF fault function output of the FX-30 (later FX-50) exciter to automatically switch from a faulted exciter to one that is working.  Finally, it can be hooked to a remote control for manual switching.  The un-used exciter is muted and routed to a dummy load mounted on the back of the unit.

Broadcast Electronics FW-30 front, mid 1980's BE blue

Broadcast Electronics FW-30 front, mid 1980's BE blue

An alternate configuration would be to route the backup exciter to the backup transmitter instead of the dummy load.  This would create the best redundancy on a limited equipment budget.  It also has a battery bank designed to hold the last state of the unit through a power outage.  As we have a good sized UPS powering the remote control, STLs and satellite receivers, the batteries are not needed.

On the face of it, a pretty good idea.  I have had a few exciters fail over the years, which normally means the backup transmitter is placed in service by remote.

I did download the manual, but since it is currently listed on the BE website, it’s probably not a good idea to post the schematic.  Suffice to say, it is a tad bit complicated what with all the CMOS logic and that.  It is very possible to duplicate the functions of this equipment with a simple RF forward power sample and set a failure threshold with a comparator circuit.  Hook that to a small four port coax switch and a couple of RF mute/un-mute commands to each exciter and: Viola!  Automatic exciter switching!

Perhaps a good rainy day project.

Driving and the hazards thereof

Not really a technical thing, but is something that I have to deal with as a self employed contractor.  The big change for me between being an employee versus someone who is self employed is the amount of driving I do on a day to day basis.  The group of engineers that I work with cover an area from New York City all the way up to the Canadian boarder.  On any given day, I can be in Bridgeport CT or Albany, NY or Burlington, VT or White Plains, NY.  The miles pile up quickly.

While out driving around, I get to see many new things.  For example, yesterday I drove by the County Sheriff’s car:

Sherrif department armored vehicle

County Sheriff's department armored vehicle, courtesy of NorthJersey.com

Something has changed, but I can’t quite put my finger on it.

The fact that I drive so many miles means that there will almost certainly be some interaction with local law enforcement, especially on that late night trip to or from a transmitter site.  As one State Trooper once put it, nothing good happens after 11pm, which seemed to be enough to trigger reasonable suspicion and a traffic stop.

Of course, the police officers executing traffic stops are doing their jobs and the best course of action is cooperate and maintain a polite, professional disposition.  Usually, a traffic stop goes something like this:

While driving down the road, you notice a police car behind you.  At some point, the lights will come on and you pull over, the police car pulls up behind you.  At this point, you roll down the driver side window, put the car in park (or neutral) and turn off the engine.  Do not start rooting around for the registration, get out your wallet, unlatch your seat belt or anything else, just sit there.  The police officer will run your plate, which may take a few minutes.  Then, after some period of time, he (or she) will get out of the police car and approach your vehicle on the driver’s side.  When you see him approach, place both hands on the steering wheel, so that he (or she) can see them.  The exchange will go something like this:

Police officer: Do you know why I pulled you over?

Yourself: No, I do not.  (That is always the reply, even if you have a good idea why you were pulled over)

PO: You were (speeding, running a stop sign, red light or the general crossing road lines, unable to maintain lanes, unsafe lane change, etc) (fill in the blank).

Yourself: I was not aware of that.

From here, the interaction can take any number of routes; you may be able to explain what was going on, he may let  you off with a warning, or you may get a ticket. As the driver, you will have to gauge the situation.  Many times, I have found the best course is to explain that you are a radio (or TV) engineer on your way to or from some specific emergency somewhere.  Many times, this will be enough, so long as the police officer does not suspect you of drinking or something similar.

Other times, the generic “you crossed the white (or yellow) line” will be used a fishing expedition and he is looking for drunk driving, warrants, drugs or something else to arrest you for.  The most important thing to remember is not to give him that reason.

The police officer will ask you for your license and registration, he may ask you to step out of the car, take a field sobriety test, ask questions about items in the car, etc. Answer the specific question and no more, do not get chatty, volunteer information, etc.

If a traffic citation is issued, follow the directions, mail it in on time and plead not guilty.  Some form of trial will take place, often, before the proceeding, the prosecuting attorney or police officer will approach you and offer a plea to some lesser charge.  To avoid wasting a lot of time on a trial, make the best deal possible and pay the fine.

On the other hand, if there is time to spare, go ahead with the trial.  There are many ways to get out of a speeding ticket, especially if RADAR was used in the traffic stop.  The law of sines is a good way to shoot holes in a police officer’s RADAR testimony.  I like this one, because, in order for RADAR to be accurate, the measurement must be taken from dead ahead.  Any angle to either side and the relative speed of the vehicle to the RADAR gun is reduced as a function of the sine of the angle.  The greater the angle, the less the relative speed.  Other things like calibration procedures (which can be checked), last time the instrument was calibrated, time interval between the use of the RADAR gun and passage of vehicle(s), did the police officer loose sight of your vehicle, etc.

I have gone to trial twice for speeding tickets, lost one because the system was rigged (this was on Guam) and won the other because the police officer lost sight of my vehicle while he turned around to catch me.  That was on a back road, where there were multiple places to enter or exit the roadway and I was something like two miles away from the point of the infraction.

With any profession that requires a lot of driving, especially late at night, some interaction with local law enforcement will take place.  Be polite, use common sense, be professional, don’t take any shit but don’t create any bigger problems either.

Burk Autopilot

The old version of the software, that is. I like the graphical interface, just one glance is all that is needed:

Burk auto pilot

Burk auto pilot

I have not had a chance to fool around with the newer version, the screen shots on the Burk website look a little bit different.

The set up and programming of macros is pretty easy; power/pattern change times, Pre-sunrise, post sunset functions, automatic tower light monitoring, AM Directional Antenna readings, and automatic transmitter restoration routines.  If programmed correctly, the software can eliminate many of those late night/early morning phone calls, which is always a good goal.

Back when transmitters used to look like something

Other than a humming box, that is.  RCA broadcast, prior to the period in the seventies just before they went out of business, made some good looking transmitters:

RCA BTA-10U AM transmitter

RCA BTA-10U AM transmitter

The Art Deco design was favored for a number of years, especially with the AM units:

RCA BTA-1AR transmitter, circa 1960

RCA BTA-1AR transmitter, circa 1960

Some of these RCA transmitters are still in service as backups.

GE made the BT-25A, which was a 50 KW transmitter in Syracuse, NY for a few years. These units were very similar to the RCA BTA-50 transmitters.

GE BT-25-A

GE BT-25-A looking from the control cabinet

Gates of Parker Gates, pre-Harris, also made some classic transmitters:

Gates BC1J transmitter

Gates BC1J AM transmitter

I remember the BC5P had a similar look, with more transmitter cabinets.

Bauer FB5000J AM transmitter

Bauer FB5000J AM transmitter

Fritz Bauer made a very solid AM transmitter.  Good looking, too.  We need more pictures of old transmitters and other hardware.


Good troubleshooters are becoming rare these days.  To some, the idea of working through a problem, finding and then fixing an issue seems like a time consuming, wasteful evolution.  More often than not, it is easier to replace the entire assembly with a new one, throwing the old one away.  This is especially true with computer components.  The other option is to send a module or assembly back to the factory for repair.  Truth be told, often that is a good course of action when a fully equipped repair bench is not available.  Surface mount technology can be difficult to repair in the field, as can many RF components.

Being able to trouble shoot components and assemblies is still a valuable skill.  Finding and identifying trouble is a good skill no matter what it is used for.  I find analytical troubleshooting skills to be good life skill to have.  I think my in-laws are occasionally amazed when I walk into a situation and point to something and say: There it is, fix that.

Coil burned out on 40 amp RF contactor

Coil burned out on 40 amp RF contactor

Many times, however, there is no smoking gun. Those situations require a bit of investigative work. The first step in troubleshooting is developing a history:

  • Has this failed before
  • It there is history of failures
  • Has it been worked on recently
  • Is it new
  • Has it been installed properly
  • It it old
  • Has it been effected by some outside force like lightning or a power surge

This is where good maintenance records or maintenance logs come in handy.  Recently, I have found many places that lack any type of maintenance documents, which means the repair history is unknown.  This makes it difficult to find a good starting point and can greatly increase the amount of time required to troubleshoot a problem.

Once the pertinent history is gathered, it can be organized and analyzed for clues.  For example, if something has been worked on recently, that is a good place to start. If something has a past history of failures, that is a good place to start.  Newly installed equipment is subject early failures under warranty due to component failures.  Old equipment may just be plumb worn out.  Improperly installed equipment can exhibit all kinds of bizarre failure modes.   That information coupled with known symptoms would indicate a good starting point for troubleshooting the problem.

If no good starting point can be discerned, then the next step is to recreate the failure.  This usually means turning the thing back on to see what it does.  Chances are good that whatever the problem is, it will still be their.  Once a good set of symptoms have been identified, then it is time to start working at one end of the problem unit the fail component is isolated.

Often times, equipment manuals will have troubleshooting guides.  These can greatly speed up the process for large, complicated things like transmitters, generators, and so on.  There is also the tried and true troubleshooting chart:

Generic transmitter power supply trouble shooting chart

Generic transmitter power supply trouble shooting chart

This is an example of a troubleshooting chart for a transmitter power supply.  Many equipment manuals will have this type of information in the maintenance sections.

It is also important to note that when working on high voltage systems, it is necessary to have two persons on site at all times.

Good troubleshooting skills have many applications.

The 4CX250B ceramic tube

4CX250B ceramic vacuum tube

4CX250B ceramic vacuum tube

It’s a cute little thing.  These were often used for driver tubes in FM broadcast transmitters.   With the naming conventions of ceramic tubes, we can tell quite a bit about the unit without even looking at the data sheet.

  • The first number is indicates the number of grids in the tube, 3 makes it a triode, 4 tetrote and 5 pentode.
  • The C means it is a ceramic tube
  • The X indicates it is air cooled, a V is vapor cooled, W is water cooled, M is multiphase
  • The 250 is the plate dissipation is watts
  • B is the design revision.

Thus a 4CV100,000 is a vapor cooled tube capable of dissipating 100,000 watts, something one might find in a high powered MF or HF transmitter.

Other bits of critical information about tubes would be maximum plate voltage, maximum screen voltage, maximum grid voltage, maximum screen dissipation, maximum grid dissipation and filament voltage.  Something to keep in mind when tuning a transmitter.

This particular tube is installed in the driver section of a Continental 816R2 transmitter.

Continental 816R2 driver section

Continental 816R2 driver section

I have noticed that these tubes have a much shorter life than there predecessors.  Back ten or twenty years ago, they usually lasted 12-14 months.  The latest set lasted only 8 months and both units failed catastrophically.  That points to one of two things; either something in the transmitter has changed or something in the way the tubes are manufactured has changed.  Once the new tubes were installed, I checked all of the parameters against previous maintenance logs.  I also checked things like air flow, dirt and other possible culprits.

I could find no changes in the transmitter.  The only thing I can think of is the fact that the tubes are installed horizontally, which causes the elements to warp and eventually break or short.

Continental 816R2 transmitter, WFLY, Troy, NY

Continental 816R2 transmitter, WFLY, Troy, NY

I am thinking we may try to convert the driver section of this transmitter to a solid state unit.  The transmitter itself is 24 years old, but is still works and sounds great.  I’d hate to get rid of it because of its driver section.

Why is Digital Radio needed?

Perhaps it is a good time to pose a few questions regarding the future of radio broadcasting and digital radio in particular.  For this article, I will assume that everyone understands that digital radio is a type of modulation using data transmitted at high speeds, which is reassembled in the receiver to generate audio for the listener.

  1. Why is digital radio needed?
  2. What are the benefits of transitioning to digital radio?
  3. Who would benefit most?
  4. Who would benefit least?
  5. What are the alternatives to digital radio?
  6. Why or why not proceed with the transition already started?

To answer the first question, we need to understand the current consumer market place and the all pervasive notion of disruptive (aka destructive) innovation.  That is to say, a new technology that builds on existing technology or knowledge, while eventually replacing or destroying its predecessor.  Think; horse and buggy vs. automobile, microwave network vs. fiber optic network, wired telephone network vs. cellular phones or film photography vs digital photography.  In other words, the older technology becomes obsolete and is abandoned in view of the improvements brought on by innovations.

Disruptive Technology

Disruptive Technology

No one can argue that innovations have not greatly improved our lifestyle and productivity in the last one hundred years.  Few would opt to permanently return to an era of no electricity, no electronic communications, and no cars.  In order for the destructive innovation argument to succeed, however, the technology in question must be improved in a way that benefits the greater society.

Digital modulation methods have been under development since ATT started using T-carriers to transmit telephone calls over long distance circuits.  Over the years, several different methods were developed including Phase (or Frequency) Shift Keying (PSK), Multiple Phase Shift Keying (QPSK), Quadrature Amplitude Modulation (QAM), and Orthogonal Frequency Division Multiplexing (ODFM).

For various purposes, these digital modulation methods offer distinct advantages over analog modulation methods.

Thus, the proponents of digital radio broadcasting postulate the advantages of transitioning to a digital radio are:

  • Improved sound quality, often using terms like “CD Quality,” etc
  • Improved spectrum efficiency, more broadcasting channels for the same amount of frequency allotted.
  • Improved coverage area, less interference, out of band noise, etc
  • Value added accessories, such as data services (song title and artist), album art, Electronic Programming Guide, H. 264 video, etc
  • Keep up with evolving technology

Thus, the question of why digital radio is needed is answered by listing the possible benefits of such a transition.  By the list of benefits above, most consumers would find improvements in digital radio broadcasting as would most broadcasters.  In theory, it is not a bad idea.

In the real world, theory and application are often radically different.  Innovation is most often, although not always, driven by a profit motive.  Digital radio technology is no different.  The proponents of digital radio are attempting to move technology forward while making profit.  There is nothing wrong with that, provided the consumer sees the value in the new technology and embraces it.  That is a key part of the current digital radio puzzle which is missing; the consumer.

Unfortunately for digital radio broadcasting, several of the above benefits have not been fully realized in the first iteration of the technology.  In several countries, digital radio has taken the form of IBOC via either DRM or HD Radio®.  Others choose to do DAB via Eureka 147.  In almost every case, the average consumer has not embraced the new technology for several reasons:

  1. Coincidentally with the roll out of IBOC, the mobile internet has become pervasive by use of things like smart phones, tablets and similar devices.  Via 3G and 4G mobile networks, consumers can access almost an unlimited number of programming choices from across the world.
  2. Programming offerings on digital radio differ only slightly with those available on analog radio.  Consumers are left with no compelling reason to purchase or install a digital radio.
  3. The technical advantages of digital radio are not consistent enough or significant enough to make a difference in the listening experience.
  4. The availability of other competing entertainment mediums such as MP3 players, satellite radio (XM/Sirius), internet streaming, etc.

Many point out that internet type services require and internet service provider (ISP), mobile data plans, or some other type of paid service.  Further; 3G, 4G and or WiFi services are not universally available.  All of that may be true, however, mobile data networks are rolling out far faster than IBOC.  Consumers appear to be willing to pay for internet service for a variety of reasons, including mobile listening.

The major flaw of the internet technology is a capability of ISPs cut off service at the request of the government for any reason.  There is also the ability to block access to certain websites, countries, search results, or services.  There are several bills currently under consideration in Congress to codify this, which is an ominous development.  Eventually, one of these bills will make it through and become law, creating some form of censorship on the internet.  In light of the potential issues with the internet, free, over the air broadcasting is necessary, if not vital, to democracy provided the ownership is dispersed and diverse.

There are distinct advantages to digital radio broadcasting which may be realized with different systems that are developed in the future.  It may require a re-think of what it means to be a broadcaster and how to make digital radio broadcasting more like IP based interactive web streaming, available for free using different frequencies than what are in use currently.  The general public has shown, by their lack of interest, that digital radio broadcasting as is being carried out today is not necessary.  While digital modulation has been around for quite some time, the politics and bureaucracy involved with creating a digital radio broadcasting service has stunted development, making the technology almost irrelevant.

Shut up! shut up! I am working Cape Race

So sent wireless operator John “Jack”  Phillips on the night of April 14th, 1912, and likely sealed the fate of some 1,514 passengers and crew of the RMS Titanic, radio call sign MGY.  That message was sent in response to the radio operator on the SS Californian/MWL, who was attempting to report icebergs nearby.

RMS Titanic side view

RMS Titanic side view

Of course, it would be a gross error to blame the sinking of the Titanic on the radio operator, he was but one small link in a long chain of events that unwound that fateful night one hundred years ago.  Beginning with the ship’s design and ending with the Captain of the Titanic, Edward Smith, many seemingly unconnected decisions lead up to the ultimate disaster that befell the Titanic.

After about four days at sea, during the late morning/early afternoon of April the 14th, the Titanic began receiving wireless messages indicating “growlers, bergs and ice fields” were in the area.  The Captain decided to alter the ship’s course to the south, out of the supposed ice fields.

In spite of numerous reports of nearby ice, the Captain did not order the ship to reduce speed.  It continued on at 22 knots (41 kp/h)  up until the time it struck the berg.  Lookouts were posted in the crows nest, near the bow, to spot icebergs.  This was considered normal operating procedure at the time, but is the most significant factor in the collision.  A number of nearby ships had spotted ice and had greatly reduced speed or stopped for the night.  Further exacerbating the situation, the lookouts on the Titanic did not have binoculars, which was due to a mix up before they sailed from England.

Some of the ice reports received later in the day and evening did not make it to the bridge.  Wireless operator Jack Phillips was either repairing a malfunctioning spark gap transmitter or was sending messages from passengers to Cape Race Radio/MCE, Newfoundland.  At the time, the (wireless) radio operators were not a part of ship’s company, but rather were employed by the Marconi Company for the purpose of sending messages for profit.  Any notion of safety or distress communication was an afterthought.

The SS Californian, closest ship to the Titanic at the time it sunk, was attempting to broadcast another ice warning to all ships in the area at about 10:30 pm.  The message was broken off by Phillips with a terse: “SHUT UP! SHUT UP! I AM WORKING CAPE RACE”  At about 11:30 pm, Cyril Evans, the Californian radio operator closed station and went to bed. Ten minutes later, the Titanic struck the iceberg.

5 KW synchronous rotary spark gap transmitter

5 KW synchronous rotary spark gap transmitter

The Titanic used a 5 KW synchronous rotary spark gap transmitter, which was state of the art at the time.  The power is measured at the input of the DC motor.  Considering the efficiencies of the motor and generator, the ability of the spark gap to generate RF and the efficiency of the tuning circuits and antenna, the actual power radiated by the transmitting antenna would have been significantly less, on the order of a couple of hundred watts.   The above schematic is not exactly the same as the unit installed on the Titanic, as the meters and additional controls for motor speed and generator voltage have been omitted.   Additionally, some sources report the transmitter as a 1.5 KW non-synchronous unit.  The difference between the two would be very apparent in the sound of the received signal; a synchronous transmitter had a tonal quality to it versus a non-synchronous or simple spark gap, which sounded like hissing.  Wireless operators from shore stations and other ships who worked the Titanic reported that they were using a synchronous unit.

The transmitter used two frequencies; 600 meters, or 500 KHz and 300 meters, or 1,000 KHz.  Because of these frequencies, maximum range during daylight hours was about 200-400 miles (322-644 km).  Night time, the ranges were considerably more, 1,000-2,000 miles (1600-3200 km), which is typical for medium frequencies, including the AM or standard broadcast band in use today.  Thus the effort by the Titanic radio operators to clear the backlog of message traffic out during darkness, when Cape Race was about 374 miles (602 km) away.

Another part of the problem was with the transmitting and receiving apparatus itself.  The transmitters were crude and generated broad harsh signals.  The receivers were also very broad, and nearby transmitting stations could easily wipe out all frequencies on early receivers.  That is what likely prompted Phillips’ outburst, something termed today as blanketing interference.  Vacuum tubes (aka valves) had yet to accepted for wide spread use as amplifiers and most receivers were simple tuned circuits connected to a detector of some type.  As such, receivers were far less sensitive and selective than they are today.

Interestingly, the Titanic had both types of receiver on board.  The main receiver was a tuned circuit with a Marconi Magnetic detector (aka “Maggie”) and a valve receiver as a backup.  The valve or vacuum tube was likely a simple diode detector connected to a tuned circuit.

After the collision, Jack Phillips stayed at his post sending out distress messages and communicating with other ships en route to assist.  Long after the Captain told the radio operators they were dismissed, Phillips persisted until power was lost and the radio room began flooding.  He perished shortly after in the 28° F (-2°C) water, however, assistant operator, Harold Bride, survived.

There is also some bit of discussion about the rudder commands given after the iceberg was sighted.  Most accounts say First officer, William Murdoch, gave the command “Hard over starboard” which would be the equivalent of right full rudder, effectively turning the ship to the left.

As rudders work, the amount of water flowing over the rudder determines its effectiveness or loading (resistance to water flow).  With the center screw turning at full speed, the rudder would have quickly loaded and pushed the rear of the ship away from center line by re-vectoring the water coming from the propellers.  There is no way to know if this would have changed the outcome as not enough is known about the maneuverability of the Titanic.  Her sea trials consisted of about seven hours of sailing time before passengers were embarked.

The next commands issued were “full astern,”  on the engine room telegraph.  Because of the design of the ship, it took about thirty seconds to engage the rudder and backing engines.  The ship continued straight ahead at 22 knots (11 meters per second), traveling 372 yards (340 meters) before beginning to turn.  The center screw had no reverse, so it was simply stopped.  Once the engines were reversed, the rudder lost much of its effectiveness due to turbulent flow and stalling.  The ship could not maneuver around the iceberg, striking it in a glancing blow springing the hull plating in five forward compartments on the starboard side.

As it was the Titanic’s maiden voyage, the first officer did not have much deck time and was likely less familiar with the maneuvering characteristics of the ship versus other ships he had conned.  On most other ships of the time, including the SS Californian, which had just completed the identical maneuver, that combination of rudder and engine room telegraph commands would have been appropriate to stop and swing the ship around the berg.

The SS Californian was within sight of the Titanic as it sunk, observing several “rockets” (as many as eight) being fired. When informed of the rockets, the Captain of the Californian asked their color, but did not move to investigate or waken the wireless operator.  According to some of Californian bridge crew, the Titanic looked strange in the water, like something was wrong.  The Californian attempted to signal the Titanic with blinking light, which was not acknowledged.  Inexplicably, the Californian never attempted to investigate further until 5:30am the next morning when wireless operator Evans was back on duty and reported the sinking to the bridge.

Therefore, the entire chain of events that led up to the disaster include:

  1. Too few life boats for passengers and crew
  2. Not enough training in deployment of life boats
  3. Very short sea trail period for the ship’s crew before passengers were embarked
  4. Over confidence in the water tight door system in keeping the ship afloat
  5. Binoculars for lookouts not procured in time for sailing
  6. Ship’s rate of speed too fast for conditions, with numerous reports of ice in the area
  7. Ship’s radio operator dismissing ice report from nearest ship (almost within view at the time) so he could continue to send paid message traffic
  8. Combination of helm and engine room telegraph commands did not produce optimum maneuvering
  9. Failure of nearest ship to recognize distress flares (or rockets) as such and render assistance

Change any one of those nine things and the outcome might be entirely different.  Something to ponder.

The result of this disaster was the formal codification shipboard safety requirements known as SOLAS or Safety Of Life At Sea.  Those standards include the transmission of distress signals, distress communications, numbers of life boats, radio watches, fire suppression systems, and training for passengers and crew.  Currently the distress communication system is known as the Global Maritime Distress Safety System or GMDSS.

RoHS and Electronics Reliability

ROHS stands for Restriction of Hazardous Substances Directive. It is a mainly European effort to reduce lead (Pb), Mercury (Hg), Cadmium (Cd), Hexavalent Chromium (Cr+6), Polybrominated Biphenyl (PBB), Polybrominated diphenyl ethers (PBDE) and Acrylamide in electronics and consumer goods.

The main effort appears to be in the reduction of lead in circuit boards and solder.  Generally speaking, reduction of pollutants is a good thing.  Lead is a toxic, especially to young children. Mercury is a potent neurotoxin.  Those other elements and chemicals don’t sound good either.

There are all sorts of green logos and other nice looking things attached to products which meet the standard.

Typical ROHS label

Typical ROHS label

I feel better, don’t you?

Now for the other side of ROHS.  According to Lead Free Electronics Reliability (large .pdf) by Dr. Andrew Kostic, the effort had been hugely expensive with very limited results:

A huge (~ $14B annual revenue) semiconductor manufacturer estimated the annual worldwide Pb reduction per 1,000,000,000 integrated circuits was only equivalent to ~100 automobile batteries.

Wow!  That is simply amazing on the face of it.  Over the years, I have probably found and carted at least 10 old car batteries to the recycling center for a few dollars each.  According to the Kostic paper:

(Computer chip manufacturer) Intel’s efforts to remove lead from its chips have so far cost the company more than $100 million and there is no clear end in sight to the project’s mounting costs

Wouldn’t $100m be better spent on other, more pressing pollution issues?  Fukushima, springs to mind.

Further, the replacement metals used in electronics have some problems of their own.  They may be better for the environment, however, they lack testing and are

Not optimized for high reliability, severe stress, long life applications

Further, replacing parts in legacy equipment using ROHS parts and solder may present problems with bonds between dissimilar metals.  Thus, making field repairs, or any repairs impossible.

Many of the newer solders and circuit boards use Tin (Sn) as the finishing metal.  There is a problem with tin, known as Tin whiskers.  This was first noted at the Bell Labs in 1947.  Small hairs grow out of the surface of the metal, acting as short circuits, and at higher (above 6 GHz) frequency RF, antennas.   This happens with other metals such as Zinc, Silver, and Gold.

Silver Sulfide Whiskers on circuit board

Silver Sulfide Whiskers on circuit board

As you can probably deduce, this can have certain detrimental effects on the performance of the circuits in question.  I can imagine all sorts of strange behavior from controllers and other bits and parts of equipment.

I don’t know how prevalent this is in Europe where the directive has been in effect for 6 years or so.  It would be interesting to find out.  I also wonder how many US manufactures are adopting RoHS as the de faco standard in order to do business in Europe.

Free climbing in Russia

Tower climbing in Russia. Caution is advised if you are fearful of heights or suffer from vertigo. Last time I posted something like this, there were all sorts of comments about OHSA violations and the like.

Ain’t no OHSA in Russia, son.

h/t: Broadcast Engineering Facebook Group


A pessimist sees the glass as half empty. An optimist sees the glass as half full. The engineer sees the glass as twice the size it needs to be.

Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press; or the right of the people peaceably to assemble, and to petition the Government for a redress of grievances.
~1st amendment to the United States Constitution

Any society that would give up a little liberty to gain a little security will deserve neither and lose both.
~Benjamin Franklin

The individual has always had to struggle to keep from being overwhelmed by the tribe. To be your own man is hard business. If you try it, you will be lonely often, and sometimes frightened. But no price is too high to pay for the privilege of owning yourself.
~Rudyard Kipling

Everyone has the right to freedom of opinion and expression; this right includes the freedom to hold opinions without interference and to seek, receive and impart information and ideas through any media and regardless of frontiers
~Universal Declaration Of Human Rights, Article 19

...radio was discovered, and not invented, and that these frequencies and principles were always in existence long before man was aware of them. Therefore, no one owns them. They are there as free as sunlight, which is a higher frequency form of the same energy.
~Alan Weiner

Free counters!