The "big new tower" mentioned in this article was a reference to the on-going construction of the Navy's new high-power station, NAA, in Arlington, Virginia.
The American Jeweler, July, 1912, pages 259-260:
WIRELESS TIME FOR JEWELERS.
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By H. E. DUNCAN.
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Indiana Retail Jewelers' Convention.
When the sale of a timepiece is made, it is safe to assume that the purchaser has in mind a certain degree of time-keeping excellence in his purchase, and that he should not be disappointed in this respect. If his purchase was based on the claims of the $1 pocket clock made in its advertisements, or worse still, the claims of the department stores of "the best at one-half price" that fill our daily press, it is my opinion that he will be disappointed, and in his dissatisfaction he will blame the jeweler or his workman. How many dealers in watches--I call them the legitimate jeweler and the watchmaker--are today beyond the possibility of being classed under the many uncomplimentary heads named by the dissatisfied purchaser?
Gentlemen, this condition will remain as long as you continue to sell timepieces without knowing yourself how well they will run before you sell them. When selling you are asked to warrant them, and you do so. Why is not such a procedure a plain gamble on your part? You do not know how they will run. You think the manufacturer has had that in hand, and you will take a chance on that; so does the department store owner, and his chances of success are as good as yours. If all watches remained in the condition in which they left the hands of the makers, then would the purchaser judge the watch and its makers by its performance when he got it; but if through some cause they are not in that condition, then by proper timing will they tell where they are at? Do you yourself know this, or do you take your chances--gamble, I call it? A standard Webster defines as something established by authority, and standard time in the United States is obtained from the Naval Observatory at Washington, D.C., or its only branch at the navy yard, Mare Island, on the Pacific coast.
They obtain their time from star transits, noting the error of their clocks, as Δ Τ (Delta Tau). Now this means that their clocks are never on exact time, and they are positive of their error only at the instant of observation. After that it is based on what the clock or standard has done in the past, and what it will probably do up to the instant of the next observation; and this is called the projected rate. They can tell you to the fraction of a second how much each clock varies from this standard--the fixed stars--at any day, hour and minute of the year past, but not for the year to come, as that is not known. Once a day they set a secondary clock, or transmitting clock, as near as possible on time without the error of the standard clocks (and it is very close on time you may feel confident), and at about noon they connect this clock with the Western Union Telegraph Company lines, and they transmit the beats of this observatory clock over their lines for five minutes. Any failure to transmit these beats, or inaccuracy in doing so, is not the fault of the clock; it is due to the telegraph company, and the limitations of its instruments and electrical conditions.
The United States Naval Observatory can tell you each day what the slight error of their transmitting clock was. Who can check up on the time taken from the wires? Is it the same as that sent out by the Naval Observatory?
Now, one step more. The Naval Observatory makes no charge for the standard time to any one, but can you get it for nothing? If so, it is not the usual experience. But, gentlemen, we are on the eve of a new condition--a condition I am pleased to state that the company I represent has already availed themselves of obtaining the "ticks" of the Naval Observatory transmitting clock by wireless waves. This new method of transmission is in its infancy now, but it is not too early for you to study up a little and get in line to keep in your proper position before your public as the local authority for standard time.
Before considering the necessary equipment to grab the time signals as they go by as wireless waves we will first take up the wave itself. You must not lose sight of the fact that with the making of the wave; or in plainer words, the transmission of the signal, we will have nothing to do. We must put all our attention on detecting the passing of a wave; or to repeat myself, it's the receiving not the transmitting we are after.
First, let us take the air as an example of motion. With a fan in your hand you can so wave the fan that a person near you can feel the motion (a breeze you may call it); and if the motion of the fan is not too rapid, you can count its vibrations by counting the impulses you feel in the air. You will also note that the more power you put into the fan's motion the greater will be the effect in moving the air (let us call it air waves). Most things in the path of these air waves will interrupt or deflect them, or neutralize the power expended in moving the fan. We could go further as an example of these waves and say that if they were counted we can classify many of them by pitch or musical tones. Four hundred and fifty waves per second is one of the standards.
While sound will travel in the form of waves in the air it will not do so in a vacuum; yet light will. And accepting the scientific explanation that light travels as waves and can be reflected, condensed and dispersed, that it will pass through a vacuum, but sound will not. Then light doesn't depend on air to transmit its waves. Now light is made up of waves of different length; mix them all up and we have white light, or daylight; but science says there are many kinds of light waves we do not see with our limited eyesight. Some of these light waves are not put out of commission, but go on or pass through many things that we once thought would stop light; but science proved itself correct with the X-ray. It requires the sensitive photographic plate to record their passage; the human eye can not do it.
Now we come to this fact, that while sound will travel as air waves, light must use some other medium; something that is more fluid or flexible than air, and this medium is called ether. As water will flow between rocks or sand, so will ether flow through almost all known matter, but not always with the same ease or freedom; and this is called resistance. Magnetic and light waves are both waves of the ether in motion but at different speeds or rapidity of vibration.
The United States government will transmit the wireless time signals. At first they may not have in mind the jeweler, but later they will be recognized and their wants will be freely met by a suitable service.
I am at present using a Clapp-Eastham receiving set, contained in a mahogany box on a shelf on the wall, and the reading of the signals is made with a pair of telephones with a head strap.
The next thing required is the aerial or antenna. There are many kinds of these, but they may be briefly described as a grid of about 150 feet of wire suspended in mid air and a vertical wire leading from the grid to the instruments.
As we fail to detect the X-ray waves of light with the human eye, so will the human ear fail to detect the magnetic waves of the wireless signal. In the former instance we use the photographic plate; in the latter, the telephone. Wireless waves at the rate of 100,000 per second are about the slowest of any practical value.
In the establishment of a receiving station in the ordinary place of business, the first thing to be considered is that of the aerial or antenna, as it is usually called. It would be well to base your estimates of the aerial on 150 feet of copper wire, something about No. 15 Brown and Sharpe's gauge. This will work out nicely as one piece of wire, or you can cut it up into four pieces, 25 feet long, putting them up, as it were, in the form of a gridiron. Now when these are suspended they must have no contact with the ground. They gather the magnetic waves as they pass through the air. Should they accidentally have contact with the ground, you would lose all the effect; but supposing you decide to use the four strands of 25 feet long, the first thing to consider is the distance of the station that is sending out those signals. The more distant the station and the weaker the power, the more energy they must have, or the greater surface of wire to gather in the waves for your use. It is safe to say that with 150 feet of wire, at 75 to 100 feet high, properly insulated or protected from ground currents, the average commercial or government station signals can be picked up at 150 miles distant.
If these wires are outside the building, and oftentimes they are stretched between two buildings and over a street, you must keep in mind one thing: You are liable to invite electricity in the form of lightning, and to that end to avoid all accidents most cities have an insurance clause or an electric inspection clause that requires a good sized wire to be run from the aerial to the ground, and which will be operative at all times except when the line is in use receiving signals.
The next is the receiving instrument. The receiving instrument is introduced in the wire, called the lead-in wire, that leads from the aerial to the receiver, through the receiver and out to a suitable ground connection, which is preferably a water pipe or a large sheet of metal buried deep in the earth if there are no pipes. In the degree of excellence of this ground depends much of the success of your receiving set. The receiving set, properly speaking, consists of a coil of wire wound on some kind of an insulated cylinder, and every time the electric waves pass your aerial they cause an exceedingly small amount of magnetic current to flow down from the aerial through the lead-in wire, around this coil, and so on to the earth.
Now by making a similar coil of wire on another cylinder and slipping it inside this first cylinder, yet not touching it in any way, we have the second part of the coil, known as the induction coil. The duty of this coil is to recognize any magnetic current that passes through the first, or receiving coil, and intensify it. This intensification is subject to more or less adjustment by slipping the coil out or in as may be necessary to get the signals more plainly to the ear. Now these currents are so exceedingly small that the ear would not detect them; yet if you pass them through a pair of very fine-wound (or high resistance) telephones you will hear the disturbance; that is, you will note the passage of a wave.
The transmitting instruments at the main station that is sending out these waves do not send them out as one long electric movement, but it is a series of exceedingly fine pulsations, as I have stated before, not less than 100,000 per second. To those that have never heard the message or waves coming in on the phone I can best describe what you hear as being similar to the ringing of an electric door-bell; technically speaking, it is a buzzing sound like the bee, or like the sound of a humming bird. Now we have come to the receipt and interpretation of the signals. If it was a regular wireless message, you would put the receivers to your ears and wait until somebody sent a message, and then you could hear more or less distinctly these little buzzing sounds. They, translated into letters of the Morse alphabet, mean dots and dashes. The shortest possible dot of vibration that you could distinguish would be known as E, and if five of those should follow in rapid succession it would be the numeral 5.
But here is where there is a little difference between taking the time signals and taking the regular wireless message. The government will, when the time comes, send out their signals at some stated hour. You will not have to listen and wait sometimes a half hour for some message to be sent; but at the hour and minute when the government signals are due you will go to your instruments, put the telephones on your ears and wait the beating of the transmitting clock. When you begin to hear the beats (and there will be no mistake on your part) all you have to have near you is some timepiece, or be within sight of your standard clock, and you can note the difference between those signals and the time shown by your clock.
At the present time the government is sending out signals from four stations on the Pacific coast, and eleven stations on the Atlantic coast, giving the time to mariners. Jewelers who are within the radius of any of these stations can, if they wish, equip themselves with the wireless at an expense of not over thirty-five dollars, plus the expense of the aerial receiving sets in addition to this, and avail themselves of those signals. When the big new tower is done everybody will be in range of the main station. Understand, that after you have once set your instruments the chances are that except for lightning or some other interference with the adjustment of your coil you will not have to do any tuning or changing whatever, as you would if you were to endeavor to take messages from various stations throughout your territory.
I think it is safe to say that when the government is prepared to send out signals for the benefit of the people inland, which will be sometime next fall, they will do so after the close of business hours, for at that time there will be less disturbing causes from the outside. You will get your signals with less interference during those hours. One of the greatest causes of the disturbances of the day at the present time is local noises within the room where your instruments are situated, as when a wireless signal comes from a distance of 200 or 300 miles, it is very faint and will not admit of much noise in the room in which you are trying to read the signals.