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- I asked Jim Wades, the President of the Morse Telegraph Club, *
- to provide some insight into telegraph lines on railroad *
- rights-of-way, Postal Telegraph, and the technical part of *
- Jim's answer is a bit more involved than the usual post we *
- see, but please bear with me - Jim is an expert in railroad *
- signals and telegraphy, and it's a good introduciton to the *
- subject for non-technical readers. *
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Bill,
The [previous posts are] a bit disjointed, but I will do my best to provide some insights. In the interest of linearity, I will break it down in to several subjects:
First, with respect to the nature of telegraph circuits:
I am leaving out significant technical detail here in the interest of space/time, however, telegraph circuits in commercial service can generally be subdivided as follows:
- The simplex ground return circuit: This is the classic telegraph circuit, with a single current loop in the range of 100 to 300-VDC at 60 to 100-mA operating over typically an iron wire with ground return.
- The duplex circuit, using the bridge principle, thereby allowing two telegraph circuits to operate on a single wire.
- The quadraplex circuit, based on a similar principle to the above, allowing four circuits to operate on a single wire.
- The carrier system, which began to emerge with stable vacuum tube oscillators and audio filters in the mid 1920s, which allowed multiple telegraph carriers to be carried on a single wire.
- The composite telegraph circuit.
The later circuit was most typically utilized by the Bell System, because it allowed a telegraph circuit to be composited over voice circuits. This allowed telegraphy to be utilized for internal communications as well as leased telegraph/teleprinter circuits on the same circuit carrying long-distance voice calls and the like. As the wire/cable infrastructure was (and is) one of the most expensive parts of a carrier's infrastructure, this allowed long-distance telephone circuits to remain in valuable revenue service while being used as order wires and the like or providing a dedicated telegraph circuit for various business, press, or similar applications, thereby minimizing overhead and maximizing toll revenue. These methods were in widespread use through the 1950s in the Bell System.
Many of those employed in telecommunications today recall carrier systems and the like, so they need not be discussed in detail here. Railroads and telecom providers were still using such systems well into the 1970s and '80s, and there is likely significant Information available on the web. Carrier systems were even deployed during World War Two for telecommunications, railroad operating battalions (telegraph, etc.), and the like.
As to the simplex and duplex systems, these are relatively self-explanatory and probably require little elaboration.
Now....as to pole line along railroad right-of-way:
The pole line one encounters along railroad right-of-way typically carried three types of "communications:"
- Telegraph
- Telephone
- Signal control ("Code Line")
In many cases, the order of precedence on the poles was:
Leased lines / WU, and the like at the top. RR Phone and Telegraph middle Code Line (RR signals) on the bottom
Not always.....but this was the norm on the railroads I was associated with.
The last telegraph lines used in railroad service were decommissioned in the mid 1980s. However, the telegraph was in slow decline in rail service beginning in the late 1950s, typically replaced with teletype and VHF two-way radio, then, of course, computers. However, manual Morse circuits were simple, reliable, and in many ways more accurate and faster than voice for certain types of specialized traffic; particularly message traffic that had to be transcribed.
The telephone has been a part of rail operations since the early 1900s as well. Both were used to varying extent for varying applications on major railroads. In later years, the telephone circuits were primarily used for wayside communications between train crews and dispatcher at switches, control points, and the like. This, of course, was later supplemented, then eventually replaced with VHF-FM radio in the 160-MHz range. In later years, the phone and radio were used for dispatching, whereas telegraph and TTY were used for car reports, internal business coordination, and occasionally dispatching on branch lines and the like
Code line was, and still is in some cases, essentially current loops similar to telegraph loops. One can find 20 to 60-mA loops running between control points to actuate vital relay logic and the like as part of CTC systems. These methods are likewise disappearing as they are replaced with "coded track," which uses the rail as a conductor for a form of data communications between control points, as well "radio code line" applications, which utilize a type of packet switched radio network for communications between control points and the like.
One will see much abandoned pole line in the field. However, some pole line is also in use in many areas as of yet. Also...beware, it was common practice to send 220 or 440-VAC on opposite outer conductors to power the various signal apparatus along the right-of-way. Some of this remains in service, and coming in contact with it can be a "shocking" experience for those who might want to climb a pole to liberate a few antique insulators.
Now....as to ownership of poles.
Years ago (through 1950s or so), it was common for Western Union to provide the poles and similar components, and the railroad to provide the maintenance and right-of-way. It was a winner for the railroads. When I worked for CSX some years ago, we still had WU telegraph poles supporting active code line. LOL: it had long ago surpassed the initial return on investment. As WU moved away from traditional pole line, the RR took ownership and eventually had to replace many of the poles, cross-arms, and the like at their own expense.
Please note that Postal Telegraph typically did not run along railroad right-of-way. Rather, Postal ran their pole line along highways, such as the famous "Lincoln Highway," "Telegraph Avenue" in the Detroit area, and the like.
OK....on to Postal Telegraph:
Postal was established with the encouragement of certain forces within the government, but as a private entity and part of the MacKay system out of a degree of fear of the WU monopoly. This fear was especially problematic in the early part of the 20th century when WU merged with the Bell System (to be ultimately broken up under anti-trust laws during the Wilson Administration, if I recall correctly). There is much history here, and it is too in depth to go into. Again, I suspect one can find considerable information on-line or in a good quality text book on the subject (contact me for a recommendation). Simply put, WU was the "Microsoft" of its day. It did many good things by standardizing the telegraph industry. It also suffered from some similar problems associated with excessive market place dominance. I suppose the same could be said of the Bell System.
Postal was always the poorer cousin of WU. It tended to serve metropolitan areas and medium sized cities. Through the McKay system, it did offer access to submarine cable circuits, marine radiogram facilities, and the like, which were advantageous. However, even in private, leased services, WU and the Bell System were far ahead, particularly as technical advancements brought forth Varioplex (concentrator) circuits, reperforator centers, and the like.
WU also pioneered a high degree of automation and even microwave carrier. Information on their transition to teleprinter operation and reperforator centers is readily available. Postal tried to match them in this area. However, when Postal was merged into WU in the 1943 time period, much of the Postal TTY and reperforator equipment was sent to the former Soviet Union under lend-lease. Rumor has it that when one sends a telegram to the former Soviet Union today, it occasionally passes over this network! LOL.
Finally...as to repeaters, etc.
Yes, repeaters were necessary. In North American Signal practice, the telegraph is a closed-loop system. For example, one must close his/her key to receive. This is why one sees a "circuit closer" on telegraph keys. Contrary to the popular belief of ham radio operators, it's primary purpose is not for "tuning up" a radio transmitter. LOL. When one wants to send, he must open his key. He then opens and closes the circuit with dots and dashes (or later..in the TTY era, the baudot code!).
When one "breaks" a communications circuit, he opened the series loop, the transmitting office's sounder went quiet, and the transmitting operator knew the receiving operator had missed something. Good operators didn't break very often! There were exceptions. For example, one couldn't "break" some types of circuits (duplex, etc), so the receiving operator had to be on his game.
The spacing and distance between repeaters was based on number of instruments in the series circuit (main line relays/sounders, etc.), nature of the infrastructure (leakage, resistive losses in the lines (iron or copper wire, wire diameter), etc.), but a couple hundred miles is a good rule of thumb, I suppose.
Typically, a "wire chief" was assigned at COs and divisional points. He was equipped with a test board and a good bridge (like a Leeds and Northrup ZM-3). By knowing the type and nature of the pole line, he could pin-point opens, shorts, and similar faults to a fairly narrow area, speeding the inspection and repair of damaged pole line.
Speaking of repeaters....If one would like to see a Bell System Athearn Repeater, which is currently in service linking the Morse Telegraph Club's Internet based "KOB" network with an older telegraph "hub" system constructed by former ATT engineer Ace Holman, just go to "you tube" at:
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... [and] you can see a brief overview provided by yours truly.
Repeaters in and of themselves are an entire discussion. It seems that in the late 19th and early 20th century, every erstwhile telegraph/telephone engineer was looking for a way to invent a better repeater! LOL There are many ways of accomplishing the task.
In summary...I have provided only a brief summary of information on a complex subject. The telegraph is often represented in a highly simplistic manner. However, the technology of the telegraph served as the foundation for every aspect of our modern life. Today, people are impressed that they can buy and sell stocks on-line, but they overlook the fact that the New York Stock Exchange is an International exchange because of the telegraph. Folks are impressed that they can get the latest news on their "I-Pod," but the telegraph made news syndication, wire services, and the like possible! The infrastructure that supported the telegraph industry was vast and complex. One could establish a circuit from Alaska to NYC in a few minutes for a press application, brokerages could transmit a buy or sell order to the NYSE or Board of Trade and get a response in minutes, and telegrams moved with incredible speed and efficiency considering the state of the art.
There are still quite a few telegraph operators around. Many of these men and women are members of the "Morse Telegraph Club, Inc." Interested parties are invited to visit our web page at:
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Membership is open to anyone with an interest in the history or telegraphy and telecommunications, and the group publishes an excellent quarterly periodical.
They may also find the "Morse KOB" program interesting. This system allows one to connect authentic telegraph instruments operating in a local current loop into an Internet based system. The instruments function just as they would on a "real" telegraph circuit, and 24-hour news and weather broadcasts are available to drive a telegraph sounder. Check:
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Folks with questions about telegraphy or MTC may also contact me directly, if they wish.
Thanks for the inquiry, Bill.
73,
Jim
James Wades International President, Morse Telegraph Club, Inc. snipped-for-privacy@remove-this.gmail.com