| Author |
Message |
    
Tarn Stephanos
Member
Username: titanictarn
Post Number: 969
Registered: 1-2002
| | Posted on Monday, January 26, 2004 - 2:52 am: | 
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I have read the day before the sinking, some gadget in the Marconi room broke down, and it took all day for Phillips and Bride to find and repair the problem.
I suspect Parks might know the answer to this.
What exactly was the problem, and is that particular piece of equipment in the silent room, or marcooni room?
thanks
Tarn Stephanos |
Brian R Peterson
Member
Username: brian_peterson
Post Number: 419
Registered: 8-2003
| | Posted on Wednesday, January 28, 2004 - 3:44 am: |
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Hi Tarn,
The transformer in the Silent Room was what was giving Bride and Phillips an issue on April 13th.
The device had failed during the night and was not repaired and operational again until nearly 5:00am, this was the main part of the reason Bride and Phillips were so backed up with passenger messages.
Best Regards,
Brian |
Tarn Stephanos
Member
Username: titanictarn
Post Number: 975
Registered: 1-2002
| | Posted on Wednesday, January 28, 2004 - 6:13 pm: |
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Thanks for the information Brian!
Per chance do you know exactly what broke down within the transformer, and what they did to effect repeairs?
I assume it was a short of some kind?
Can you imagine what would have happened had the transformer broken down right before the collision?
The death toll certiasnly would have been higher.
It seems Titanic had one stroke of good luck in that the transformer was repaired before the collision with the iceberg...
regards
Tarn Stephanos |
Kritina Johnston
Member
Username: kjohnston
Post Number: 221
Registered: 5-2001
| | Posted on Wednesday, January 28, 2004 - 7:55 pm: |
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Marcus covers this in brief detail in his book...but maybe Parks will get to this thread before someone feels the need to resort to transcribing out the relevant passages!!!!
I am a flaming, raging, drag fatalist.
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Dave Gittins
Member
Username: gittins
Post Number: 1685
Registered: 4-2001
| | Posted on Wednesday, January 28, 2004 - 8:02 pm: |
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Tarn, you are correct. It was a short. A lead from the secondary coil of a transformer somehow came in contact with a metal part of the equipment. Phillips and Bride spent most of the time looking at a condenser which they thought had failed. Once they spotted the real trouble, they fixed it in a few minutes with insulating tape.
Bride told the tale to The New York Times but the reporter wrote 'secretary' instead of 'secondary'. Proof of the gap in transmissions can be seen in "Signals of Disaster". You can see where Titanic came back on the air soon after 2-00 a.m. New York Time. It's questionable whether the incident really held up many passenger messages. The main reason for the backlog was that Phillips saved them for Sunday night, when he could contact shore stations directly. He seems to have cleared the few messages he had on hand in the hour after the radio was fixed. |
Parks Stephenson
Member
Username: sparks
Post Number: 1199
Registered: 4-2001
| | Posted on Wednesday, January 28, 2004 - 8:38 pm: |
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Sorry, I was so tied up with another thread that I didn't see this one until now. Dave explained it correctly.
A little more detail, if you're interested:
The transformer consisted primarily of two coils, or windings, of copper wire, wound over a soft-iron core. The secondary winding was divided into two parts so that they could be configured to operate in either series or parallel (depending on whether it was desired to transmit on the long or short wave). Connected to the secondaries were a pair of choke coils, whose purpose it was to protect the secondary windings of the transformer from being damaged (i.e., insulation being burned through, exposing bare copper wire) by the high potential of the osciallatory circuit. Evidently, one or both of the choking coils didn't do their job properly and as a result, there was heat buildup somewhere in the secondary, which burned through the insulation, allowing exposed wire to come in contact with the transformer casing. Where exactly the short occurred cannot be determined from Bride's account, but I suspect that since the transformer casing held high-flash insulating oil into which the coils were immersed, and Phillips was reported to have fixed the issue with insulating tape, that the short occurred at the point where the leads for the secondary were brought to the terminal; in other words, up high in the casing and above the level of the oil.
The transformer was and still is in the Silent Room, in the aft port corner. The choking coils that once hung on the wall above it have fallen to rest on the top of the transformer casing. The bare copper wires that connected the choking coils to the secondary terminals are still there, although one broke when the coils settled. The brass bars used to configure the secondary terminals are still in the parallel configuration, proving that Titanic was operating the long wave (as expected). I wouldn't mind recovering the transformer, lifting the lid, and examining Phillips's patch work.
By the way, the maintenance manual for the Marconi telegraph set warns operators not to attempt to diagnose or fix a fault in any of the high-tension (high-power) components. It instead advises them to operate off the induction coil of the emergency set until such time as Marconi engineers can fix the problem. Phillips showed remarkable initiative in analysing and fixing the apparatus on his own...and it's a good thing he did, too.
Parks
http://marconigraph.com
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Kritina Johnston
Member
Username: kjohnston
Post Number: 222
Registered: 5-2001
| | Posted on Wednesday, January 28, 2004 - 9:22 pm: |
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Hmm, Stephenson and Gittins to the rescue...couple of latter-day white knights, it would seem.
I am a flaming, raging, drag fatalist.
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Parks Stephenson
Member
Username: sparks
Post Number: 1200
Registered: 4-2001
| | Posted on Wednesday, January 28, 2004 - 9:40 pm: |
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No, Kritina, just a couple of nuts who immerse themselves in Titanic minutia in a sad attempt at avoiding the difficulties of everyday living in the real world.
I think that the proper term is "geek."
(grin)
Parks
http://marconigraph.com
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Tarn Stephanos
Member
Username: titanictarn
Post Number: 977
Registered: 1-2002
| | Posted on Wednesday, January 28, 2004 - 10:09 pm: |
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Thanks Parks and Dave....
Your collective knowledge of marconi lore never ceases to amaze me..
I wonder if there are any traces of the repair still evident in the trasformer...
Perhaps there are remnants of the insulating tape?
I wonder if Olympic's Marconi equipment experinced similar breakdowns..
THANK YOU for the detailed information....
regards
tarn Stephanos |
Kritina Johnston
Member
Username: kjohnston
Post Number: 224
Registered: 5-2001
| | Posted on Thursday, January 29, 2004 - 8:21 am: |
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"I think that the proper term is "geek." "
And what is wrong with that? It's from the efforts of the dedicated that the rest of us junkies get what we need!!!!! It's a win-win situation. 
I am a flaming, raging, drag fatalist.
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Dave Gittins
Member
Username: gittins
Post Number: 1687
Registered: 4-2001
| | Posted on Friday, January 30, 2004 - 5:59 am: |
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I wouldn't class myself as a geek when it comes to radio, but I do have some interesting material from an Australian radio ham who has replicated many devices from the Titanic era, including a rotary spark unit and a magnetic detector.
I look forward to Parks explaining, in words of fewer than three syllables, how the "Maggie" worked. I sort of understand it, and apparently "sort of" is about all most people manage. It seems Marconi himself didn't fully understand it, but it worked, so it lingered on for years. Truly an amazing gizmo. |
Parks Stephenson
Member
Username: sparks
Post Number: 1204
Registered: 4-2001
| | Posted on Friday, January 30, 2004 - 6:36 am: |
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I look forward to Parks explaining, in words of fewer than three syllables, how the "Maggie" worked.
No fair, Dave. I'll try, but I can't guarantee that I won't slip up and use a multisyllabic word now and again (and "multisyllabic" doesn't count because I haven't started yet).
The Maggie had a clockwork mechanism that kept a continuous band of soft iron moving through two sets of coils. Above each coil sat a set of horseshoe magnets. As the iron band moved past the magnets, the attraction of the iron pulled the lines of force of the magnets' field along with it. As the band passed from North pole to South pole of each magnet, the direction of magnetism was reversed.
Now for the interesting part. Signals received through the aerial were routed through the small coils, which had both primary and secondary turns of wire. The aerial was connected to the primary. When the aerial current flowed through the primary, it changed the state of magnetism in the moving band. When it didn't flow, there was no change to the normal state of magnetism. This change was picked up by the secondary by induction, which passed it to a condenser in the form of a vibration, where it was amplified so that it would significantly impact the diaphragms of the headphones.
Does this explanation help? I left some detail out for the sake of brevity, assuming that you could fill the gaps with your own understanding.
If the horseshoe magnets were arranged so that like poles were together (S-N-N-S), there was a hissing, or "breathing," sound heard in the headphones. If the poles were arranged in a N-S-N-S configuration, the hissing was eliminated, but the sensitivity of the receiver was lessened. Arrangements of the magnets was therefore a personal choice of the individual operator. Sometimes, operators used the hissing sound as an audible fault indicator...if the "breathing" stopped, then the clockwork needed to be rewound or the band had stopped for some reason.
Would your friend have the initials P.J. by any chance? If so, I have tried communicating with him in private, but have gotten the impression that he does not think very highly of me. Our conversation faded after only a couple of e-mail exchanges.
Parks
http://marconigraph.com
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Brian R Peterson
Member
Username: brian_peterson
Post Number: 423
Registered: 8-2003
| | Posted on Friday, January 30, 2004 - 8:17 am: |
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Hi Parks,
I am fascinated by the workings of the Titanic era wireless, could you send me a private message with a more detailed description of the above post as I have little knowledge of the actual system itself.
Best Regards,
Brian |
Parks Stephenson
Member
Username: sparks
Post Number: 1205
Registered: 4-2001
| | Posted on Friday, January 30, 2004 - 4:10 pm: |
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Brian,
Instead of doling this out piecemeal, why don't we wait until my book on the Marconi apparatus gets published later this year. In that book, I will have detailed descriptions of every single component of the apparatus, along with pictures, schematics, exploded views, etc. If you really want to learn about Titanic's wireless apparatus, that's the way to do it...at least, that's my motivation for writing the book.
Parks
http://marconigraph.com
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Dave Gittins
Member
Username: gittins
Post Number: 1688
Registered: 4-2001
| | Posted on Friday, January 30, 2004 - 11:31 pm: |
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Parks, his initials are indeed PJ. I wouldn't call him a friend. My experience was much the same as yours. No doubt he has plenty of other things to do. He's an architect and town planner when he's not playing with radios. |
Brian R Peterson
Member
Username: brian_peterson
Post Number: 430
Registered: 8-2003
| | Posted on Saturday, January 31, 2004 - 12:21 am: |
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Hi Parks,
Thanks for that tidbit of info Parks! I was not aware that you were publishing a book on the topic, but I do look forward to it coming out, what is its title so I know what to look for 
Best Regards,
Brian |
Parks Stephenson
Member
Username: sparks
Post Number: 1207
Registered: 4-2001
| | Posted on Saturday, January 31, 2004 - 12:53 am: |
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Dave,
It's good to know that his apparent nonchalance is not personal. I was a little put off when he asked why I was bothering to model the Marconi rooms when their form was already known, stated that the Olympic pictures are good enough for our understanding of Titanic, and expressed doubt that Titanic carried a 5kW set.
At least I have learned from his past work and can build upon it.
Brian,
I don't have a name for the book yet, because I have learned that publishers usually choose the name that they think will sell lots of copies. Even if I do have a say in the title, I want to wait until the book nears completion before I select one. Don't worry, though...I'll put out advance notice here on E-T, so everyone who wants one will have an opportunity to order.
Parks
http://marconigraph.com
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Robert T. Paige
Member
Username: jnb
Post Number: 146
Registered: 5-2005
| | Posted on Wednesday, August 24, 2005 - 1:32 am: |
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Parks-
I see you haven't been on this thread since 31 January 2004, but maybe you'll catch this one.:
What was the frequency of the tone of the Marconi transmitters ? I'm basing my opinion of around 440 HZ since it is reported to be the frequency at which the human ear "hears" best and I remember a shipboard radar that used an electric motor driven spark gap for modulation. However, the transmissions would have probably been more of a "buzz" than a musical note as heard on present day CW code transmissions. Any comments will be welcomed. Just a bit of curiosity on the subject.
Regards,
Robert |
Robert T. Paige
Member
Username: jnb
Post Number: 148
Registered: 5-2005
| | Posted on Wednesday, August 24, 2005 - 5:22 am: |
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I'm referring to the audio frequency as heard in the 'phones. |
Parks Stephenson
Member
Username: sparks
Post Number: 1822
Registered: 4-2001
| | Posted on Wednesday, August 24, 2005 - 4:33 pm: |
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Robert,
Most of the merchant ships, Titanic included, of that era were restricted to two frequencies for transmit and receive: the long wave (600 metre, or 500 kHz) and the short wave (300 metre, or 1000 kHz). Normally, the ships conversed on the long wave. The apparatus had to be physically reconfigured to work the short wave, and therefore the short wave was rarely used. Everybody talked on one frequency.
Most of the ships operating that night were equipped with plain spark dischargers. For the 5-kW apparatus installed aboard Olympic, the spark was the result of the condenser discharge across two stationary electrodes. This would result in the "buzz" that you mentioned. Titanic, though, was the only ship in the area that night that carried a rotary spark discharger. 16 electrodes spun at high RPM past two stationary electrodes, with multiple spark discharges combining to produce a 60-Hz tone that approximated the sound you hear in later CW systems. Much lower in tone than present-day systems, but completely different from the other plain-spark sets. That's why, when Titanic called, she sounded completely different from any other ship.
Parks
http://marconigraph.com
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Samuel Halpern
Member
Username: cmdrsam
Post Number: 689
Registered: 3-2003
| | Posted on Wednesday, August 24, 2005 - 5:15 pm: |
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Hi Parks. Thought you may be interested in a reference I have from early 1900s that describes a 1.5 Kw Marconi set for shipboard use that offers a Marconi disk discharger on the shaft of the 4-pole DC to AC converter. They list the nominal rotational speed at 1500 rpm producing AC at 50 Hz. The disk discharger had equally spaced discharge electrodes that spun across a pair of stationary electrodes. They said it would cause spark discharges from 300 to 600 per second. Assuming there were 16 electrodes on the disk, and the disk rotated at exactly 1500 rpm, that would produce a fundamental audio tone at 400 Hz. I would have assumed that a 5 Kw set would produce similar sounding tones in the 300 - 600 Hz range.
By the way, the signaling key used in the primary of the charging transformer was actually a relay key actuated off of the Morse key used by the operator. This key remained closed after the operator would release his key until the AC cycle passed through 0 thus avoiding unnecessary sparking in the charging transformer's primary circuit.
There are no Unsinkable Theories.
Sam Halpern
40° 23' 50'' N, 74° 13' 55'' W.
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Parks Stephenson
Member
Username: sparks
Post Number: 1823
Registered: 4-2001
| | Posted on Wednesday, August 24, 2005 - 7:11 pm: |
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Sam,
Sounds like the 8-stud disc is described in your reference. Titanic had double the number of discharges, about 1200 per second. I mispoke above -- the result of posting at work while my reference material is at home -- the audio tone would be around 400 Hz. The AC output is around 60 Hz.
The magnetic relay key was meant to prevent high-voltage sparking at the transmitting key contacts, which would unnecessarily burn down the contact points and present a sparking hazard to the operator. The 1.5-kW sets had a magnetic relay key with one coil...the 5-kW sets had a double-coil key.
Thanks for the info,
Parks
http://marconigraph.com
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Robert T. Paige
Member
Username: jnb
Post Number: 149
Registered: 5-2005
| | Posted on Thursday, August 25, 2005 - 3:47 am: |
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Hi Parks and Sam-
Thanks very much for all the information which has answered all my questions. IMO the audio of the transmissions in ANTR has always impressed me as being the most authentic.
-Robert |
Robert T. Paige
Member
Username: jnb
Post Number: 318
Registered: 5-2005
| | Posted on Sunday, March 12, 2006 - 2:17 am: |
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All "Jack and Rose" comments aside, there is a lot of detail in "Titanic" (1997).
In the "Deleted Scenes" in the "Special Edition" set of 3 DVD's, there is a scene in the Marconi Room on Californian. The cover appears to be off of the detector and the details of the wheels, wires and inductors can be clearly seen in the background. (This is seen only briefly and it's best to step this through and "freeze frame" to see the details.)
"The best I've seen, ma'am....Hardly any rats."
Robert T. Paige
32 51' 18" N 97 00' 18" W
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Parks Stephenson
Member
Username: sparks
Post Number: 1970
Registered: 4-2001
| | Posted on Sunday, March 12, 2006 - 4:14 pm: |
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Robert,
Yes, there is no cover on the Maggie prop used on both Titanic and Californian Marconi sets. When the reproduction prop was built, for some reason the cover was never built (maybe as a cost savings measure? maybe the original used as a reference didn't have a cover? I don't know).
The original Marconi props (most of which survived the film production) are displayed at the Foxploration exhibit in Rosarito Beach, Mexico. I re-arranged the display just last year to more accurately reflect the historical Titanic, rather than the film version, for the LMoT documentary. You can see photos of the exhibit -- both versions -- on my website in the Foxploration Virtual Tour article in the Cape Race section. You will notice the uncovered Maggie in both photos.
Parks
http://marconigraph.com
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Jonathan Granato
Member
Username: jake_angus
Post Number: 157
Registered: 5-2004
| | Posted on Monday, March 13, 2006 - 4:26 am: |
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Jack P.'s bday was April 12th. I doubt he had much of a chance to celebrate. |
Robert T. Paige
Member
Username: jnb
Post Number: 319
Registered: 5-2005
| | Posted on Monday, March 13, 2006 - 4:28 am: |
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Parks-
Thanks very much. Fascinating website !
-Robert
"The best I've seen, ma'am....Hardly any rats."
Robert T. Paige
32 51' 18" N 97 00' 18" W
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Robert T. Paige
Member
Username: jnb
Post Number: 322
Registered: 5-2005
| | Posted on Thursday, March 16, 2006 - 5:35 am: |
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Another question for Parks :
What would be heard on the Marconi Magnetic Detector in the case of an AM,CW,MCW,NBFM,FM or
SSB transmission being received ? In other words, did it work only for receiving spark transmissions ?
However, most likely it would have never been used for other than "spark" since technology had developed better detectors by the time the more advanced modes had come into use ?
"The best I've seen, ma'am....Hardly any rats."
Robert T. Paige
32 51' 18" N 97 00' 18" W
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Parks Stephenson
Member
Username: sparks
Post Number: 1976
Registered: 4-2001
| | Posted on Thursday, March 16, 2006 - 3:57 pm: |
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Robert,
A lot of what you mentioned hadn't been developed by 1912. But even so, the Maggie is only designed to pick up the kind of electromagnetic oscillations generated by spark sets.
Essentially, the Maggie consisted of two spools, driven by a clockwork mechanism, around which an iron band was run. Two sets of horseshoe magnets were positioned on either side of the band run and as the band passed beneath the magnets, any electromagnetic oscillation induced into the circuit (the Maggie was connected directly to the aerial) was attracted/repulsed by the magnets, which caused a deflection in the moving band. This deflection created an electric pulse in a coil and that pulse was sent to the tuner. At this stage, the pulse was too faint to be detected by the human ear...a telephone condenser downstream of the tuner would perform that amplification.
It was a very primitive system and unable to detect any kind of modulated signal. The tuner used tunable condensers to filter out unwanted oscillations. However, this was considered a reliable system for the time, much more reliable than the earlier coherer detector.
Parks
http://marconigraph.com
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Robert T. Paige
Member
Username: jnb
Post Number: 323
Registered: 5-2005
| | Posted on Thursday, March 16, 2006 - 10:10 pm: |
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Thanks again, Parks...That answers my question of "Just wondering what if " a Marconi Detector had still been around when the other mediums of transmissions came into being if anything would have been heard...most likely nothing. Also, by the time the other methods of transmission had come into being they also moved to the "short waves".
"The best I've seen, ma'am....Hardly any rats."
Robert T. Paige
32 51' 18" N 97 00' 18" W
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Robert T. Paige
Member
Username: jnb
Post Number: 324
Registered: 5-2005
| | Posted on Thursday, March 16, 2006 - 10:23 pm: |
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Also....Would the Titanic's signals have been heard as clearly (on Californian's Marconi Room) as heard in the sound track in "A Night to Remember" ? However, I believe "the real story" is that Third Officer Groves heard nothing since he did not know how to wind up the detector ? (I believe Don Lynch made a point of this in the commentary of the ANTR DVD. )
"The best I've seen, ma'am....Hardly any rats."
Robert T. Paige
32 51' 18" N 97 00' 18" W
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Parks Stephenson
Member
Username: sparks
Post Number: 1977
Registered: 4-2001
| | Posted on Thursday, March 16, 2006 - 11:30 pm: |
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Robert,
I would have to watch ANTR again to listen to the signal before I could attempt to answer your first question. You're right, though, about the "real story"...Evans had let the clockwork mechanism run down, so the iron band was not moving past the magnets in the Maggie. With no deflection of the iron band, there would be no sounds in the headphones. None of the received signals were electrically boosted -- in fact, the entire receiving apparatus was not powered by electricity -- the received oscillations were amplified instead via magnets and condensers.
Parks
http://marconigraph.com
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Yuri Singleton
Member
Username: yuris
Post Number: 606
Registered: 5-2001
| | Posted on Friday, March 17, 2006 - 4:19 am: |
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Parks,
Tangent question here:
As the ship sank, and water entered the Marconi rooms, what do you think would have been the moment by moment events, or system failure log leading to the complete failure of the wireless system? (Starting with the operators leaving and water appearing under the door.)
Assuming the unit remained in a powered, operational state until 'killed' by inundation.
As water filled the area, and came into contact with the various components in the silent room, could a condition be created where the unit transmitted a gibberish signal due to contact with water? Would it have been a gradual failure, perceptible to other receivers as a blurring of the signal, a weak gibberish signal? Or would it be an instant, hard-off termination of signal?
(I realize this may be a bigger question in scope than you have time to answer, so if you can't accomodate it rest assured I understand. It is asked spontaneously, with no importance or urgency for an immediate answer. But if you do have time I'm sure others would enjoy reading your thoughts.)
Thanks Parks,
Yuri
NC USA
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Parks Stephenson
Member
Username: sparks
Post Number: 1978
Registered: 4-2001
| | Posted on Friday, March 17, 2006 - 6:44 am: |
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Yuri,
My answer is simple...I am convinced that Phillips shut down the transmitter before he abandoned the space. The evidence I offer to support this contention is the open switch on the DC switchboard and no evidence of fire in the Silent Room.
If, however, you want me to speculate about the generation of a stray signal through contact with water, then I will say that it couldn't be done. A spark is generated by jumping an air gap, and in the case of contact with water, you would not have such a focused arc of energy. Not to mention the fact that the alternator would still need to be turning and supplying AC to the condensers in order to build up the power needed for the hi-voltage spark discharge.
If you're asking about Virginian's report of a signal ending abruptly, then I attribute that more to the AC falling below threshold, unable to generate the "pressure" (to use the 1912 term) needed for a spark to discharge across the air gaps between electrodes. In short, the DC power being supplied by the ship's dynamos was failing and could no longer run the alternator at the speed needed to generate useable AC.
For Phillips to be sending while water rose at his feet, as some (not you) have claimed, is not supported by the evidence. If water had entered the Marconi Room, as Bride was quoted to have claimed in the NYT article (the only place where he made that claim, to my knowledge), then he should also have described wading through water on the Boat Deck. To exit out to Boat Deck, Bride and Phillips would have gone forward, toward the rising water. I can't square Bride's once-quoted claim about water entering the Marconi Room with his multiple accounts of his actions on Boat Deck. I suspect the NYT reporter might have embellished Bride's account a bit.
For a number of reasons, I believe that Phillips cut power to the transmitter before abandoning the Marconi rooms. What Virginian heard was a progressive degradation of stable ship's power to the Marconi DC motor, and subsequently, to the AC alternator, until the amperage dropped below threshold, killing the spark for good.
Parks
http://marconigraph.com
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Yuri Singleton
Member
Username: yuris
Post Number: 607
Registered: 5-2001
| | Posted on Friday, March 17, 2006 - 2:40 pm: |
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Thanks for your reply Parks. Very informative discussion.
I was indeed thinking about the report from another ship that the final transmission from Titanic was observed to be two long V's.
So you feel the system was 'off' and de-energized by the time water reached the equipment. Thus no dramatic end to the unit involving sparks or fire. And no possibility of an stray signal being generated after Bride and Phillips had already left.
Thanks again.
NC USA
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Parks Stephenson
Member
Username: sparks
Post Number: 1979
Registered: 4-2001
| | Posted on Friday, March 17, 2006 - 3:35 pm: |
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Yuri,
That's correct. The only evidence of fire in that area is in the electrical distribution panel that was in the athwartships corridor forward of the Marconi Room.
Parks
http://marconigraph.com
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Robert T. Paige
Member
Username: jnb
Post Number: 325
Registered: 5-2005
| | Posted on Friday, March 17, 2006 - 9:32 pm: |
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Parks-
Thanks again for all the enlightening words.
Which brings up another question (s) :
Did all the lighting, motors, etc. on Titanic operate on AC or DC or were there separate circuits for AC and/or DC ?
Also, I'm assuming that whatever type of electricity that was generated was dependent upon steam in the first place ? (That is..When the boilers failed, there was no steam to supply the generators and hence no generation of electricity for the Marconi Room and the transmissions ended.)
What was lost first - The Marconi transmissions or the lights ?
Or still another question:
Was there an emergency power source [batteries ?]for the Marconi transmitting equipment in case the primary power source failed ? I am also assuming that no power source was required for the receiving end of the Marconi equipment ? Its "Power" was from the magnets, clockwork motor,etc. ?
My apologies if this seem to be a "loaded" question (s).
Best regards, thanks very much for keeping up the good work for those of us who are less knowledgeable.
Robert
"The best I've seen, ma'am....Hardly any rats."
Robert T. Paige
32 51' 18" N 97 00' 18" W
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Samuel Halpern
Member
Username: cmdrsam
Post Number: 1004
Registered: 3-2003
| | Posted on Friday, March 17, 2006 - 9:41 pm: |
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The Baltic (MBC) heard the Titanic (MGY) call at 11:45 PM NY time, and replied back at 11:47 PM. The Mount Temple (MLQ) reported that it did not hear anything from the Titanic since 11:47 PM NY time. The last message heard by the Carpathia (MPA) from the Titanic was at 11:55 PM NY time. At 11:58 PM NY time the Asian (MKL) hears Titanic calling SOS, answers the Titanic, but receives no reply. At 12:05 AM NY time Cape Race (MCE) says that they did not hear from the Titanic for about a half hour. This would correspond to their 11:36 PM NY time intercept of a message exchange between the Titanic and the Olympic (MKC). At 12:10 AM NY time the Virginian (MGN), about 170 miles from Titanic’s CQD position, reports: “Hear MGY calling very faintly, his power greatly reduced.” At 12:20 AM NY time the Virginian thinks it hears: “Two ‘Vs’ signaled faintly in spark similar to MGYs.” At 12:27 AM NY time the Virginian thinks it hears a faint “CQ” transmission: “Unable to make out his signal. Ended very abruptly as if power suddenly switched off.”
The interesting question remains as to what exactly did the Virginian hear at 12:10 AM, NY time, and at 12:27 AM that night? Unlike today, wireless receivers in 1912 were passive devices and not capable of amplifying signals. The loudness of a signal depended on the signal strength of the received radio frequency signal. The received signal strength depended on the power level of the transmitting station, the propagation loss along the signal path between transmitter and receiver, and gains and orientations of the transmitting and receiving antennas. And unlike most communications channels today, the radio frequencies that were used were simplex communications channels, shared by many wireless stations that were out there. In recognizing a particular transmission, the receiving operator depended on reading specific call signs (like MGY for the Titanic) as confirmation that a signal came from a particular station. They did learn, however, to recognize a particular operator’s touch on the key, as well as the unique signature tone and harmonics sent out by the spark gap generators of some of the stations. But when signals are weak, and a lot of other transmissions going on, dependence on these other factors are much less reliable. Only recognizing a call sign can one be sure as to where the transmission came from. It is possible that the last transmission sent out from the Titanic was at 12:10 NY time. After that, it is somewhat questionable. The 2 "V"s were described as "similar in spark to MGYs" by Virginian's operator in his PV, he did not say they were the same because the signals received were very weak. And the Virginian was not alone in perceiving Titanic's signals after all transmissions had stopped. According to the PV record of the Mount Temple, at 1:58 AM NY time the operator of the Birma (SBA) thought he heard a transmission from the Titanic and sent a message to MGY saying: “Steaming full speed to you; shall arrive you 6 in the morning. Hope you are safe. We are only 50 miles now.” This we know now was way after the Titanic had foundered.
Sometimes what one wants to hear, one tends to hear. According to Bride, Phillips called once or twice more after the last contact with the Carpathia, but the power was failing and there were no replies. According to Bride, the last message that Phillips sent out was a general “CQD MGY” call, and it was probably this call that the Virginian operator described as: “Hear MGY calling very faintly, his power greatly reduced.”
Bride said they abandoned the cabin about 10 minutes before the ship went down.
There are no Unsinkable Theories.
Sam Halpern
40° 23' 50'' N, 74° 13' 55'' W.
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Parks Stephenson
Member
Username: sparks
Post Number: 1980
Registered: 4-2001
| | Posted on Friday, March 17, 2006 - 11:15 pm: |
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Robert,
The Marconi transmitter was normally powered off the ship's lighting circuit. Ship's DC was used to drive a motor in the Silent Room, which in turn powered an alternator that generated the AC necessary to produce a spark. A bank of accumulators was kept charged by ship's DC and switched over to an emergency coil in the event of loss of ship's power. Based upon what I can determine, Bride and Phillips never planned to switch to the accumulators because they knew that when ship's power was lost, there would be no more time for transmitting.
Samuel,
Titanic was the only ship afloat that night with a rotary spark generator. MGY's signal would have been quite distinct from the ordinary spark transmitters, even Olympic's. I doubt that any ship out there, once they heard MGY's call-up, would confuse it with any other signal, no matter how ragged Titanic's signal might have gotten.
Some of you know that I have a book in the works on this very subject. The more recent questions are coming close to having me give away portions of my manuscript that would otherwise be selling points for the book once published. I may have to beg off from answering further questions in detail.
Parks
http://marconigraph.com
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Samuel Halpern
Member
Username: cmdrsam
Post Number: 1005
Registered: 3-2003
| | Posted on Saturday, March 18, 2006 - 3:10 am: |
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Yes, MGY had a rotary spark generator on board. But there were many land stations that had rotary spark generators installed by that time. My point is that there was no way for the Virginian to confirm that what he heard came from MGY at that time. Two Vs followed 7 minutes later by a CQ may have come from anywhere. The timing of those transmissions, heard only by the Virginian, makes it doubtful that they actually came from MGY.
On a separate note, will you book be covering the wireless systems other than Marconi? The quenched spark system of the German's perhaps? From what I read some time ago in some very old technical books dealing with wireless telegraphy, the quenched spark system was much more efficient than any other at the time.
There are no Unsinkable Theories.
Sam Halpern
40° 23' 50'' N, 74° 13' 55'' W.
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Parks Stephenson
Member
Username: sparks
Post Number: 1981
Registered: 4-2001
| | Posted on Saturday, March 18, 2006 - 4:43 am: |
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Sam,
Virginian could not have heard any land station where she was. Titanic had the highest and longest aerial out there, and she could just pick up Cape Race. Even MWL couldn't hear MCE.
I don't doubt that Virginian heard Titanic. What I doubt are the times. How sure are we that the clocks aboard the Virginian were set properly, or translated correctly into Titanic ship time?
Parks
http://marconigraph.com
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Parks Stephenson
Member
Username: sparks
Post Number: 1982
Registered: 4-2001
| | Posted on Saturday, March 18, 2006 - 4:49 am: |
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Sam,
I didn't answer your other question. I am restricting myself to Titanic's apparatus, maybe also Britannic's, depending on what happens later this year.
Parks
http://marconigraph.com
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Dave Gittins
Member
Username: gittins
Post Number: 2643
Registered: 4-2001
| | Posted on Saturday, March 18, 2006 - 9:30 am: |
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Actually, Virginian could hear Cape Race and was in touch at 11-50 NYT on 14 April. See her PV, which you no doubt have. Carpathia, even further away, could hear Cape Cod.
Personally, I'm inclined to think Virginian heard Titanic, if only because the signal dropped out. As to the time, she was only using a mechanical clock and it might have been out a bit, though not a lot, because of the TRs the ships exchanged.
The whole radio story is queer. I'd like to hear the opinion of an expert on skip distances. It's odd that some stations heard signals that others missed.
Dave Gittins
Titanic: Monument and Warning.
http://users.senet.com.au/~gittins/Book.html
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Parks Stephenson
Member
Username: sparks
Post Number: 1984
Registered: 4-2001
| | Posted on Saturday, March 18, 2006 - 1:52 pm: |
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OK, Dave, point taken. I shouldn't have spoken so off-the-cuff, as I am distracted by another matter at the moment.
Sam and Yuri, if you want to pursue the possibility that Virginian heard some stray signal, then I won't argue. But I won't support the notion, either. My only advice to you will be to not forget Occam's razor.
Parks
http://marconigraph.com
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liam forber
Member
Username: charmedmad
Post Number: 33
Registered: 3-2006
| | Posted on Saturday, March 18, 2006 - 11:51 am: |
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why the hell did the moarse code machine no idea what its called break down i read that shortly after the collison it gave up doesnt that stay on as long as the power is on and that stayed on till the very end
[Moderator's Note: This message, originally posted as a separate thread under a different topic, has been moved to this pre-existing one. MAB] |
Parks Stephenson
Member
Username: sparks
Post Number: 1987
Registered: 4-2001
| | Posted on Saturday, March 18, 2006 - 3:12 pm: |
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Liam,
Your message was garbled in transmission. Please reformat and try again.
Parks
http://marconigraph.com
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Samuel Halpern
Member
Username: cmdrsam
Post Number: 1007
Registered: 3-2003
| | Posted on Saturday, March 18, 2006 - 10:13 pm: |
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What I can tell you Dave is that radio propagation at night, especially during active sunspot cycles, can be very unpredictable and subject to slow fading. The Northern lights were quite active that night as reported by those in the boats. It does not surprise me that Virginian may have been able to pick up a stronger signal than the Carpathia or Mount Temple although it was much further away. I'm just saying that it wrong to assume that those two faint Vs and later a faint CQ came from the Titanic. There was no confirmation. I believe the last transmission heard very faintly by the Virginian at 12:10 AM NY time was the last sent by Phillips as it matches what Bride said was done before they abandoned the wireless cabin.
There are no Unsinkable Theories.
Sam Halpern
40° 23' 50'' N, 74° 13' 55'' W.
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Parks Stephenson
Member
Username: sparks
Post Number: 1990
Registered: 4-2001
| | Posted on Sunday, March 19, 2006 - 12:20 am: |
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Sam,
You and I will have to disagree. I found forensic evidence in the Silent Room that supports the letter "V"s coming from MGY. My detailed reasoning on this, though, I'm saving for my book.
I don't have evidence to support the faint CQD from MGY at the end. Here, though, I defer to Occam's razor and assume that it was as the Virginian claimed.
Parks
http://marconigraph.com
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Samuel Halpern
Member
Username: cmdrsam
Post Number: 1008
Registered: 3-2003
| | Posted on Sunday, March 19, 2006 - 12:31 am: |
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Now you really got me excited about this. When does it look like the book will be coming out?
There are no Unsinkable Theories.
Sam Halpern
40° 23' 50'' N, 74° 13' 55'' W.
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Parks Stephenson
Member
Username: sparks
Post Number: 1991
Registered: 4-2001
| | Posted on Sunday, March 19, 2006 - 1:54 am: |
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My book was owed to the publisher this Spring. However, my unforseen work on these TV documentaries has caused me to delay putting my pen to paper. And now, there may be a chance later this summer for me to gather more information that could be used to write the final chapters of the book. So, maybe this Autumn?
Parks
http://marconigraph.com
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