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#5,701
wg_ski said:
And you might be surprised to know how many “EE’s” have trouble with basic electronics. And with everything being dumbed down at even the university level it’s only going to get worse.
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I worked in a building that had almost 1000 engineers from varying disciplines at it's peak, out of about 5000 employees. I was of a few who had worked their way up from the assembly line into an engineering position, THEN they sent me to college for a degree at their expense....twice.

That put me in a position to have a better understanding of how all the pieces of the puzzle fit together.....and to teach this stuff to new engineers fresh out of school.

There were some really smart people who came from respected engineering schools with good GPA's, and many more with average educations, that had no idea how a two way radio or cell phone actually worked. We had to teach them before they could design one.

There were also many people who had worked there for several years who didn't totally grasp the fundamentals either, since they had been pigeon-holed into one tiny sub-section of a radio, say the frequency synthesizer, or RF power amp, and knew it well, but did not understand much else. Out of the EE's that I worked with daily, I would guess that only 50% or so had ever used a soldering iron.

I spent a good deal of my time teaching these basics to new and veteran engineers, and even had classes in a meeting room after hours. One day I slapped a slide into my deck that had a schematic from a piece of HP test equipment on it, and asked the group of about 15 people how it worked. There were long stares, and no responses. After the silence waned the question became "what are those active devices?" I replied that it should be obvious, and all the necessary information to determine that was on the slide. An older engineer who had began his education in Cuba got it first. The copyright date was in the 1950's, and they were indeed vacuum tubes.

We made cell phones. All the Nextel phones were made in our plant in Florida for the first 8 years or so. The chief product safety specialist received a burnt phone from Nextel one day, and shut down all production. All hands meetings were called to get to the bottom of this, with no clear answer.

All electrical engineers above a certain pay grade were called into a big meeting room at 9 AM to discuss the failure, how it happened, and how to prevent it. There were slides, experts, idiots, and managers presenting their ideas of how this could happen. Most were shot down by the panel of experts. Then the toasted phone was passed around with pictures of all of it's internals. Each one of the 30 or so people were asked for their explanation of how this could happen, while everyone else in the room told them how wrong they were.

I stated exactly how it happened, people laughed, and we went on. Each time it was my turn I attempted to offer a better explanation of my theory, with some real engineering evidence and explanation....and a bit of personal experience. By noon it seemed that this meeting was getting nowhere and I was getting hungry. My theory had not changed, and I had swayed only one person, also another hands on engineer with some experience in this matter.

Somewhere around 1 PM I stated that everyone in the room, even some high level bosses were ignorant, and stupid. I walked out of the room stating that I would be back in 5 minutes. I went to my desk, fetched a similar phone, then went to the break room which was filled with people eating their lunch, opened the door of a microwave oven, tossed in the phone and hit the go button. The microwave groaned, but did its job.

Then with a screwdriver in hand, walked back into the meeting room. As I opened up the phone a familiar stink filled the room. The flex circuit had identical arc marks every 1 1/8 inches, as did the plated plastic shields and the LCD screen. There were other striking similarities between the two phones. Someone asked how I did this, and I replied "20 seconds on defrost."

At this point, I had to explain that a microwave oven is a 500 to 1000 watt radio transmitter that transmits on 2.45 GHz with a horn antenna that beams that power into the target food. The 1.125 inch burn marks were the definitive clue that told me that the phone had been nuked. 1.125 inches is a quarter wavelength at 2.45 GHz. Things that are conductive, and 1/4 wavelength long will act as receiving antennas, and experience HUGE currents. Not one of the 30 or so degreed engineers, mostly RF design engineers, in the room could get this despite multiple explanations, until I offered up the smoking gun......uh phone.

Even with ample engineering proof, many will not see the facts.....especially if they just spent $200 on speaker wire, and $100 on a power cord.
 
#5,704
I had done several years in analysis of field failures on "mission critical" radios used in police, fire and other first responder situations where a person's life may depend on that radio working. We are talking about police walkie talkies that cost in the $1K to $5K PER RADIO! A these prices, they HAD to work ALWAYS.

I had analyzed several radios that had been "nuked." In this situation we worked with the customer or his radio shop which was often company owned, to trace the failure back to the moment, and method where it happened. Radios were nuked in a microwave for two reasons.

The usual stupidity factor where someone thinks that it will dry out and fix a wet radio. This is somewhat rare with expensive walkie talkies, for one because they are waterproof. Wipe them off with a rag, and keep on talking.....these things go in the hands of firemen. This is somewhat more common with phones though.

The other, and one I traced back to the security guard on the beat, was to purposely kill the radio to avoid being caught doing something that you are not supposed to do, or being somewhere you are not supposed to be. Here the user knows that nuking the radio will kill it, and possibly hide his misdeed.

One year we had bunches of mobile police radios, and Convertacom consoles dying, and even catching fire in police cruisers. A Convertacom Console is a plastic box that mounts under the dash of a cop car. The officer slides his walkie talkie into it, and the walkie talkie becomes a mobile radio. One cop, one radio, on foot or in the car.

I had designed the console for the STX radio in 1985. The consoles didn't start dying until 1987. It seems that ALL of the failures occurred in Ford Crown Vics, and NONE occurred in Chevy Caprice cop cars. All were new cop cars, so Motorola got one and stuck it inside the building for me to work on.

It took a while, but I was able to reproduce the failure. The cop car had to be running, the AC on and the compressor engaged, then the ignition turned off. The electromagnetic coil in the AC compressor generated a huge negative voltage spike when the ignition was turned off would get into the radio or console blowing a regulator chip which then fried at the next power on. Ford had changed the ignition switch so that the accessory power was lifted from the battery before the car was shut down. This left the spike generated by the clutch coil in the AC compressor nowhere to go but into the car's accessories. Some aftermarket audio equipment in non cop Crown Vics, Mercury Grand Marquis, and Lincoln Continentals was dying too.

This is why there was a little diode added onto the AC clutch in nearly all late 80's and 90's cars.
 
#5,706
It got the usual "why are you poking around under the hood of a running car with an oscilloscope?" kind of questions.

They were easier to answer than the "why are you poking around on the digital board in a phone with an RF network analyzer and an RF spectrum analyzer set for measurements in the 860 MHz region?" kind of questions from the digital engineers that designed it. The answer "I'm trying to find the RF leaks." confused them even further.

The digital board in an early Nextel phone killed the receiver on one of Nextel's channels, 856.8 MHz. It turned out to be the clock buffer in the CPU that buffered the 16.8 MHz clock to the RF board into a nice crisp square wave with clean harmonics all the way out to the 51st, which is 856.8 MHz. There was no easy fix. The on chip buffer had to be disabled and a discreet transistor buffer added with a nice slow transistor.
 
#5,709
Tubelab_com said:
It got the usual "why are you poking around under the hood of a running car with an oscilloscope?" kind of questions.

They were easier to answer than the "why are you poking around on the digital board in a phone with an RF network analyzer and an RF spectrum analyzer set for measurements in the 860 MHz region?" kind of questions from the digital engineers that designed it. The answer "I'm trying to find the RF leaks." confused them even further.

The digital board in an early Nextel phone killed the receiver on one of Nextel's channels, 856.8 MHz. It turned out to be the clock buffer in the CPU that buffered the 16.8 MHz clock to the RF board into a nice crisp square wave with clean harmonics all the way out to the 51st, which is 856.8 MHz. There was no easy fix. The on chip buffer had to be disabled and a discreet transistor buffer added with a nice slow transistor.
Click to expand...

George,

Many are educated beyond their intelligence.

Thanks DT
 
#5,711
There was a guy I worked with when I was a Mr. Fixit in the Motorola plant. His name was Jimmy Carter (easy to remember) and he was a setup technician in the thin film microelectronics group in about 1977. He seemed to understand how everything worked including scary things like the plasma etch / vapor deposition machine, but it scared him due to all the danger high voltage signs and it's propensity to make big sparks and blow 440 volt 3 phase fuses which I got to change.

One of the snobby tech guys brought in a test for membership in Mensa, a social group for Brainiacs above a certain IQ level. Myself and Jimmy were the only ones out of about 50 factory workers who passed it. Neither of us had any desire to join their club, but it brought up a discussion which led to Jimmy admitting that he had a PHD in applied chemistry from a prestigious school. When asked why he had a PHD but worked as a factory setup tech he explained that he got the PHD because going to school was far easier than working for a living, and his parents were paying. He didn't like working in PHD kind of places up north, so he got a job in a "party" kind of place, the Motorola plant in Florida.

I wouldn't say that Jimmy was educated beyond his intelligence, but educated beyond his ambition level, as getting a PHD does require a certain level of intelligence. When the microelectronics division was shipped overseas in the 80's, Jimmy was laid off and I never saw him again.

Speaking of the weather, it is currently 95 degrees F outside. I think I'll go jump in the pool.......
 
#5,712
Some of the plants affected by the heat dome from a couple months back are showing up big time now. The younger leaves nearer the top of the plants have been reduced to compost, along with any buds like on the rhodos are gone. So many are doing this.
 

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#5,713
Oscilloscopes were a great tool for ignition systems, you could diagnose all sorts of problems, from coils wired in reverse phase, what plug or wire was bad, to where in the alternator the problem was.



Still useful, but I suppose you would simulate one on a tablet today, with a breakout box for your sensors.
 
#5,715
The first thing I will do tomorrow when I get up is see if the levees are not breached and New Orleans did not fill up again.

I know they sent some people over to Amsterdam to study their pumps and floodwall systems. Knowing New Orleans government types, they likely went straight to the pot shops and then over to the red light district. Forgot whet they went there for.
 
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