Quiz Question

One of a continuing series

It’s time to quit taking these Quiz Questions seriously. Here’s one for this week.

See the above photo. What is the object pictured, and what purpose did it used to serve?

Post your answers in the comments section. It’s all right to use Google to find the answer.


Hello, I’m the 21st century, and I’m here to take your job.


TRACE, a machine that reads bank checks

I spent nearly 50 years of my life as an engineer, and I think I know when it first started. It was in 1971 that I begin to work in earnest to eliminate people’s jobs.

There was a small engineering consulting company in Austin, and we received a contract from a concern called Autotronic Systems, Inc. Ignoring the name, the company was headquartered in Houston, and they had a chain of self-service gas stations about the country. That was an innovation in 1971, pumping your own gas. It eliminated the job of the smiley attendant, who also checked your oil and wiped your windshield. Our job was to design equipment that fit inside the gas pump and recorded the amount of fuel pumped and the amount charged. The data were transmitted to another device we designed that would store daily sales data and at night phone the home office and transmit the information. Wayne van Citters and I did the software for the home office computer. People lost their jobs.

Two years later  I was working for a company in Irving, Texas, and what they did was build machinery that read the sales receipts from gas stations and did all the sales computation. Their machinery would also read bank checks, printed forms, and mail addresses on envelopes. We eliminated the jobs of the people who previously did this data entry.

In  particular, the company worked on a program to eliminate Post Office workers who eyed addresses and typed them in, or just entered the ZIP code if that was available. Twelve such work stations fed huge machines by Pitney-Bowes that then sorted the mail to the appropriate collection bins. The huge machine was appropriately call a Letter Sorter Machine (LSM). Jobs were eliminated.

I worked a few weeks at a test operation at the Post Office on 8th Avenue in Manhattan, across the street from Madison Square Garden. Postal workers did not like us. There was back room talk of workers sabotaging the machines. Eventually the company I worked for lost the contract to IBM, and I was fired. But the next day I went back  to work for them and did more mischief, eliminating jobs for several more years.

My first patent was for a machine that wrapped a band around a stack of dollar bills. It didn’t have to be one-dollar bills, it would put the strap around 100 bills of any denomination. We sold this system to the Federal Reserve Bank, and my invention eliminated the job of the person who used to put the strap on. Who wanted that job, anyway?

The same company was also a leader in the development of the ATM (automated teller machine). These machines are still around, and they have eliminated thousands of jobs in the banking industry. Docutel was the company that developed ATMs, and it was acquired by Olivetti.

Next I worked on weapons systems for the United States military. You could say I eliminated soldiers’ jobs by automating the work of killing people. My first project involved automating the location of submarines by sonar. I did the software.

My life of developing computer software aimed at eliminating the human element from all manner of tasks. My wife worked for an engineering company, and she was the business manager. She hired me to develop computer software to automate the repetitious accounting tasks. This was before the days of Quick Books.

I finally quit the business of killing jobs four years ago. It’s now the 21st century, and those jobs are not coming back. People are looking for things to do.

Donald Trump campaigned on the basis of a multitude of promises. One promise was to bring back jobs that have been lost in the coal industry. Disinterested parties have looked at this and wondered aloud who would want to go back to working in a coal mine. Nevertheless, idle miners are now looking ahead to going back underground and chewing at the coal seams, or else, sawing off the tops of mountains and scooping up the exposed coal.

But it’s not just safety and environmental concerns that are killing the coal jobs. The 21st century is killing coal jobs. Nuclear power, natural gas-fired power plants, and finally solar and wind power are killing coal jobs. These jobs are not coming back.

Progressive politicians bring us good news. Green power, they promise, will bring back the jobs lost at the coal mines. There is an enormous industry being created to produce wind turbines and solar farms. The new industry will create in the order of 100,000 new jobs, far exceeding the 30,000 lost at the mines.

Not so fast. These green power jobs are not permanent. Once the solar and wind farms are constructed and brought on-line, the industry will only need people to maintain these facilities and to expand them as power needs increase. Unlike coal, wind blows when you are not looking, and the sun comes up every morning. There is no need for the man to shovel sunshine onto a solar panel.

It’s much the same with the automobile industry. Teams of workers who used to assemble automobiles in the United States and in other countries have been replaced by robots. The major industries of electronics and computers would be impossible without the complete automation of just about all processes involved. Watch a video of computer disk drives being manufactured, and you will get an appreciation of the minuscule degree of direct human involvement.

It’s coming to be much the same in all major industries. Retail is eliminating the sales clerk who spends 30 minutes with a customer looking at a $30 pair of shoes without buying. Amazon started it with books, but the trend continues upward. The elimination of human-driven retail drives customer costs down, making it better for the economy all around, but at the cost of out-of-work sales staff.

Will there ever come a time when people will no longer need to be directly involved in producing goods and services? It’s hard to say. Many jobs I (and others) predicted would never go away are now gone for good. Economics, like nature, seeks the steady state. Eliminating jobs reduces the cost of products, but it also eliminates the customer who is supposed to pay for the products. Eventually a balance will be obtained, but at what level? In the meantime, workers are shuffling and trying to adjust, or not. The coal miners of West Virginia just defeated a candidate who promised to eliminate their jobs.

Will workers be able to vote their jobs back? Not likely. When it has been tried it has failed. Communism was a political approach to managing the economy, and it resulted in near 100% employment at the cost of dismal standards of living. This reality killed communism and the Soviet Union, but communism still thrives in the PRC, Vietnam, Laos, and Cuba. I am not mentioning North Korea, which seems to be a special case.

In conclusion, if you recently, or a long time ago, lost your job because of me, don’t bother trying to find me. First, it would not be worth your effort, and second you would be chasing the wrong perpetrator. It was the 21st century that took your job.

Friday Funny

One of a series

Airliner crosses Vineland Avenue North Hollywood while landing at Burbank Airport

Airliner crosses Vineland Avenue North Hollywood while landing at Burbank Airport

It’s Friday. There’s always something:

(CNN) — A flight to Malaysia from Sydney was diverted to Melbourne after its pilot entered incorrect coordinates of the plane’s starting position, an Australian aviation investigation report has found.

Carrying 212 passengers, the AirAsia flight bound for Kuala Lumpur on March 10, 2015, was flying in the wrong direction after takeoff from Sydney, because the pilot had manually entered the wrong coordinates of the plane’s position into the flight’s onboard navigation systems.

Isn’t modern technology wonderful. I hear the next thing they are proposing is cars that drive themselves. It’s going to be funny.

Quiz Question

One of a continuing series


Before GPS, before LORAN, navigators (ocean) determined their latitude by the angle between the sun and the horizon at noon. They determined their longitude by the time when the sun was highest in the sky (or when the sun came above the horizon). But to do that they needed to know what time it was.

At first they had hour glasses to tell the time, and it was the job of somebody to always watch the hour glass and to turn it when the sand ran down. Eventually expert clock makers devised ever more accurate clocks to help navigators determine their longitude. The advent of the telescope made it possible to get an accurate time reference that did not drift. How might that work?

Post your answer as a comment below.

Update and answer

See the comments below. Greg was onto the solution, but he didn’t carry it to conclusion. The answer is that the advent of telescopes enabled navigators to see the moons of Jupiter. There are four large ones that are visible to anybody with a good set of binoculars, and their motions provide a reliable time reference. Early navigators did make use of these observations to determine longitude with greater accuracy:

In 1612, having determined the orbital periods of Jupiter’s four brightest satellites (Io, Europa, Ganymede and Callisto), Galileo proposed that with sufficiently accurate knowledge of their orbits one could use their positions as a universal clock, which would make possible the determination of longitude. He worked on this problem from time to time during the remainder of his life.

To be successful, this method required the observation of the moons from the deck of a moving ship. To this end, Galileo proposed the celatone, a device in the form of a helmet with a telescope mounted so as to accommodate the motion of the observer on the ship. This was later replaced with the idea of a pair of nested hemispheric shells separated by a bath of oil. This would provide a platform that would allow the observer to remain stationary as the ship rolled beneath him, in the manner of a gimballed platform. To provide for the determination of time from the observed moons’ positions, a Jovilabe was offered — this was an analogue computer that calculated time from the positions and that got its name from its similarities to an astrolabe. The practical problems were severe and the method was never used at sea. However, it was used for longitude determination on land.

Quiz Question

One of a continuing series


When I was out in California a few years back there was this public service ad that kept popping up on cable TV. It featured three teens having a conversation. One little girl was being chided by her friends for leaving her phone charger plugged in when she wasn’t actually charging her phone. That sounded cool. Don’t waste electricity needlessly. Of course, not much goes into powering a smart phone charger, so it’s not like leaving the A/C turned on when you go on vacation.

Then it occurred to me that phone chargers don’t draw power when they aren’t charging the phone. And that’s this week’s Quiz Question. What’s a quick and painless way to verify your phone charger is not drawing power when it’s not charging?

Post your answer in the comments section.

Update and answer

Mike has the right idea (see the comments), but it is not as hard as he makes out. Just put your hand on your phone charger. If it’s warm, it’s dissipating (and wasting) power. You don’t need a sensitive thermometer. With most devices I’m thinking you can feel the temperature rise due to one Watt, or less.

Quiz Question

One of a continuing series


When you want to turn on the stair lights while going up the stairs, and you want to turn them off once you get to the top, you need this bit of minor technology. The lights are controlled by two switches. One switch is at the bottom of the stairs, and the other switch is at the top. The switches are “double throw” type. That means the switch is connected to two circuits, and the switch has two positions. When you toggle the switch it turns off one circuit and turns on the other. If the light was on, then throwing the switch turns the light off. If the light was off, then throwing the switch turns the light on. Neat.

Now suppose you have a three-story house, and you want to turn the stair lights on when starting up, and you want to turn the lights off when you get to the second floor, and also off when you get to the third floor if you are going that far. How are you going to be able to achieve that? Do you need a new kind of switch?

What if you have a 15-story house?

Post your answer in the comments below.


Some comments have been received, and it’s apparent clarification is needed. This Quiz Question involves single-pole, double-throw switches. Here is how a SPDT switch works:


Update and Solution

The two-switch feature can be extended to more than two switches, but the configuration I had in mind does not work. I had to go to Wikipedia for a workable solution. First, here is how the two-switch configuration works.




Switch 1 and Switch 2 are SPDT switches. In the first configuration no power is supplied to the load, which is typically a lamp. In the second configuration power is supplied to the lamp, and it turns on.

It is trivial to extrapolate from this and determine that flipping either switch turns on an off-lamp and turns off an on-lamp.

To extend this idea to more than two switch requires a different kind of switch, but still a mechanical switch. The following are from Wikipedia:

Readers are invited to visit the Wikipedia article, following which they will be able to install multi-way lighting switches for their five-story condo.

Quiz Question

One of a continuing series


Steve and Greg, hold off answering this week’s Quiz Question until some others have had a crack at it.

When you go into Home Depot and purchase some electrical wire, you will notice it comes in different sizes. Wire diameter is specified by its gauge. The deal is the smaller the gauge the thicker the wire. You may not also know that a similar gauge system is used for sheet metal. 8 gauge sheet is getting toward boiler plate thickness. 32 gauge is some thin stuff.

When it comes to shotguns, a gauge system is used to specify the bore. The very common 410 shotgun is not a gauge measure. I could be wrong, but I think a 410 has a 0.410-inch bore. The only common shotgun gauges I know are 10-gauge and 12-gauge. Doesn’t matter.

This week’s Quiz Question is, how is a shotgun gauge determined?

Provide your answer in the comments section below. No need to post your answer on Facebook. I always do that when I post the answers.

Quiz Question

One of a continuing series

Airliner crosses Vineland Avenue North Hollywood while landing at Burbank Airport

Airliner crosses Vineland Avenue North Hollywood while landing at Burbank Airport

This is a different Quiz Question. It’s possible the answer will never be known. What you need to do is to do some research. Once you have decided on your best answer, post it as a comment and state your defense of your answer. Here it is:

On 17 December 1903 nobody had ever made a flight in a powered, heavier-than-air craft. There were no airplanes in the air. Then Orville Wright flew for 12 seconds, and then he landed, and again there were no airplanes in the air.

On an unknown day a few years later there were no airplanes in the air. Then somebody took off in an airplane, flew it, and landed. But before the airplane landed, somebody else took off in another airplane. Since that time there has always been an airplane in the air.

The Quiz Question is when was the last time there was not an airplane in the air? I am counting only powered aircraft piloted by a person. Post your answer as a comment below. I will select the winner. The best answer wins Donald Trump’s $50 million prize, to be awarded his second day in office as President.

Quiz Question

One of a continuing series



Last week’s Quiz Question concerned GPS (Global Positioning System). A major issue with GPS is the variable caused by ionospheric propagation delay. Free electrons in the ionosphere slow down the signal from the satellite to the receiver, and this effect varies from day to day and with location about the Earth. Since operation of GPS relies on knowing how long (within a nanosecond) it takes the radio signal to reach the receiver, it’s critical to compensate for the ionospheric delay.

Receivers able to receive the L2 (encrypted) channel can compensate for the ionospheric delay as described in last week’s Quiz Question. Without accurate compensation the position error can be off in the order of 15 meters. When the ionospheric delay is properly compensated, the error can be reduced to the order of a few inches.

GPS has been available to the public for over 20 years, and people like farmers use GPS navigation to plow their fields. Without decoding the L2 signal they can they compute the location of their tractors to a few inches? This is done with the use of Differential GPS (DGPS), and it works this way.

Set up a GPS receiver at a known point. Use another receiver on the tractor to navigate with a few inches accuracy. Neither receiver is able to decode the L2 signal. How does DGPS accomplish this accuracy?

Post your answer as a comment below.

Update and solution

Without researching into how DGPS is implemented, I will explain a possible method. The location of the reference receiver is known. This allows it to compute the ionospheric delay. Since the other GPS receivers (for example, on the farmer’s tractor) are nearby, the ionospheric delay is the same for them. If the active GPS receivers can receive the ionospheric delay from the reference receiver, they can compensate for it and obtain their location within a few inches.

The compensation for ionospheric delay is detailed in the GPS Interface Control Document, publicly available on the Internet. Here is the link:


Quiz Question

One of a continuing series


Here’s something that came up a few years ago. It has to do with GPS technology, but you don’t need to be GPS-savvy to appreciate it. It goes like this.

GPS employs 32 satellites, whose position is at all times precisely known. Each satellite broadcasts to Earth continuously. The signal contains a lot of stuff, but the critical information from each satellite is:

  • I am here.
  • The time is …

A GPS navigation receiver doesn’t need to know the direction the signal is coming from. All that is necessary to determine your position is the preceding information from each of three or four (four is best) satellites.

From the information received, a navigator can determine where all satellites were at the same time. And it can determine how long it took each satellite’s signal to reach the receiver. Knowing the speed of propagation of the radio signal, the receiver can compute the distance to each of three (or four) known points in space and therefore compute its own position in 3-D space. If it knows the speed of propagation of the radio signal.

The problem is the speed of propagation through the atmosphere to the receiver is not constant. It varies due to the presence of free electrons in the atmosphere. There are two solutions to this difficulty. One is to incorporate an atmospheric model into the receiver’s computation, and this is done. It’s called the Klobuchar model, after the person who developed the mode. It’s not very accurate.

For extreme accuracy, the atmospheric delay can be measured directly. To do this, a second transmission channel is incorporated.

The two satellite transmission channels are called L1 and L2. All receivers can use L1. L2 is encrypted. You have to have a secret key, available only to the U.S. government, to use the L2 channel. The two channels operate on somewhat different frequencies, and the atmosphere delays each channel differently.

And that’s all you need to know if you can receive both L1 and L2. You do not need to know in advance how the atmosphere delays each channel. The receiver can deduce the atmospheric delay from each satellite, and from that it can compute the position of the receiver to very high degree of accuracy.

When I first encountered this it was obvious to me there was not enough information to compute the atmospheric delay. So I asked a guy working on the project how this was supposed to work, and he stopped what he was doing and explained it to me. I still didn’t understand it, but I took my notes back to my cube and looked at it some more. It was an “oh shit” moment. “Of course, dummy.”

And that’s this week’s quiz question. How can a GPS receiver compute the atmospheric delay from the information given, using L1 and L2?

Post your answer as a comment below. I’m going to give this a few days and then post a hint.

Update and hint

I’ve had no activity on this Quiz Question all week. It’s time to provide a hint. Look at the problem again.

You have two radio signals originating from the same location at the same time and arriving at the receiver at different times. Because of ionospheric delay, you don’t know how long it took either signal to traverse the unknown distance to the transmitter. How can you use the information available to determine the distance to the transmitter. Here is the hint.

The satellite is moving. In the order of miles per second. Its distance from the receiver changes from one transmission to the next. How can you use multiple measurements to compensate for the ionospheric delay?

Update and solution

Time’s up. I need to post the solution to last week’s Quiz Question, because tomorrow’s question is going to be related to compensating for ionospheric delay. I’m not going to do the math. Instead, I’m going to pose the question in a different way that will make the solution obvious. It goes like this:

Forget satellites. There are two rail lines running parallel for miles over the horizon. You’re standing at a point along the rail lines waiting for two trains (call them A and B) to arrive. The two trains are going to start at the same time from the same location, and they are going to come at you at different speeds. You don’t know what the speeds are, but you know the speeds of A and B are different, and they are constant.

Trains A and B arrive. A arrives shortly before B. You note the time difference. You don’t have enough information to determine how far away the station (starting point) is. You move down the line a few miles, carefully noting how far you move.

Two more trains, also labeled A and B head your way from the station. Same as before. A arrives, then B arrives later. You record the time difference. Of course the difference is greater, because you are farther from the station, so the trains have had longer to diverge.

Now you ask yourself this question. “How far do I have to walk toward the direction the trains came from for the difference to be zero?” That’s the distance to the station.

In the case of GPS with channels L1 and L2 it’s the satellite that moves, and since the satellite is always telling you where it is, you know how much farther (or closer) it has moved from you between two measurements.

There is obviously more to it, so if anybody still has questions, post a comment and extend the dialogue.