This is specifically to Parks Stephenson


I don't think he would have heard anything through the headset circuit since the receiver was shorted out during his transmission bursts while the key was depressed.

Parks, anything to add to this?
 
It has been some time since the last post on this thread, but I'll post this here in the hopes that my question might be answered. (A duplication of the same question on another thread so editor, please delete or move.)

Question: Why was the detector dependant on a purely mechanical device as a spring wound motor for operation instead of being powered by a small electric motor ? It seems the spring wound motor on the detector would eventually run down and would have had to be rewound or otherwise the operator would have heard nothing. It would seem if power by an electric motor or some electro-mechanical device to rewind the spring, the receiver would have been "live" all the time ?
 
PS- In "A Night To Remember", (Third Officer?) Groves enters the Marconi Room on Californian.
Evans, the Marconi Operator is asleep. Groves picks up the earphones (the Titanic's SOS/CQD signals are heard). Then apparently because the code is being sent so fast that Groves can't make it out,he puts the headphones down and throws the switch to silence them. I have heard that Groves actually heard nothing since he either didn't know the detector spring wound motor had run down and he either didn't know how to rewind it or did not do so.
 
Robert, I could answer your last question with the help of a little schematic drawing.

There was one antenna used for both transmitting and receiving. During transmission, the antenna was connected to ground (the ship's hull) via a small spark gap called an earth arrester. The receiving equipment was connected across this gap which essentially put it in series with the antenna as long as the gap was not shorted. However, when the transmitter was being operated, the induced current in the secondary coil of the "jigger" produced a large enough voltage across this earth arrester to cause it to discharge thereby shorting out the input to the receiver. In essence, it was an automatic relay which cut out the receiver whenever the transmitter operated.
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I have been absent for quite some time and just now got back on Encyclopedia Titanica. My apologies for the absence. I shall attempt to be more regular in my attendance. :)

Thanks for the explanation, Samuel. I suppose this would be something that was similar in the old "ATR" (Anti-Transmit-Receive) tubes in the old search radars I was assigned to during my service in the U.S. Navy. They were sort of a gas filled tube in which the gas ionized shorting out the receiver during the transmit cycle of the radar.

P.S. Would the type of receiving equipment also have been affected by interference from atmospheric conditions. In other words would "static" noise caused by lightning in an electrical storm for example and heard in the earphones of the operator ?

Also it seems spark transmission was more or less "brute force" ? Would it have been rather "broad banded" or occupying quite a bit of the spectrum on either side of the assigned frequency ?

Sorry if I have a few questions. It seems my absence opened up a can of worms . :-(

In what part of the "wireless " was the keying for the transmitter controlled ? I am assuming it must have been somewhere in the low voltage part of the circut or keying the output of the spark to the antennna would have been rather a hazard to the health of the operator at the key ?

Of course this was before the advent of the "valve" or the "vacuum tube" and everything would have been controlled either by mechanics or electricity ?
 
Dear Mr. Stephenson,

I am sitting here and watching the History Channel program, "Titanic at 100: Mystery Solved" and I have a question. The 300 pound test piece of the hull that you had exactly replicated from 100 year old iron was put to the rivet test at the University of Washington. It was determined that the rivets didn't fail quite like many have thought over the years. However, when you put that piece to the test under tens of thousands of pounds of pressure the 300 pound piece was simply at room temperature, which I am guessing was somewhere between 60 and 70 degrees fahrenheit. The waters on the night the Titanic sank were below 30 degrees fahrenheit, and furthermore the iron and rivets were subjected to this temperatures for several days. Do you think if you subjected the 300 pound test piece to these temperatures for several days before the test a different outcome would have occured? That the rivets might have failed just like they did on April 14, 1912? Steel and Iron become more brittle the colder they get, and I think that is what contributed to the rivets failing. Your test was a great test, but I don't think it was as thorough as it could have been given the test piece subjected to a below 30 degree temperature.

What do you think?
 

B-rad

Member
David, I know you said that your post was for Mr. Stephenson, but I thought you would like to read his article on the matter, posted on his site.

What Caused Titanic To Sink?

Specifically the part in which he states:

[Author's note: since our experiment was made public, almost every critic has accused us of running a faulty test because we didn't freeze the samples. In my opinion, our critics failed to comprehend the effect of the heated boiler room on the inside of the steel plating.]
 

B-rad

Member
Since posting the above post I have been thinking. The quote above would in fact only apply to the area of the boiler rooms and not the other areas in which the iceberg impacted. Did water in the peak tank effect the steel, as we know that the carpenter was sent to check on the fresh water (though the peak tanks would not be one of these tanks), in fear of freezing. Just throwing it out there. :)
 

Jim Currie

Member
Hello Brad.

The brittle rivet theory is a load of old intellectual nonsense. It is based on the ignorance of normal practice at sea.
It assumes that Titanic was deeply immersed in freezing water for a substantial amount of time. It is also based on the assumption that somehow a body of cold water was flowing over one of much warmer water.
In reality, unless the taking of sea temperature from a fast moving ship is done in a scientific manner, the results obtained and published in the Titanic Inquiries were fatally flawed. It is well known that under normal circumstances, normal sea temperature between night and day varies little more that 2 degrees. It is also know that an iceberg leaves a very shallow trail of fresh water at about 0 degrees F as it moves and is surrounded by an equally shallow pool of fresh water when stationary. An indicated sudden drop in sea temperature in 1912 was more likely to be the result of bad seawater sampling and was ans still is, no indication of the proximity of sea ice.

Jim C.
 
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