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Posted: 5/20/2020 3:27:28 PM EDT
[#1]
Good. Bring it all up.
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Posted: 5/20/2020 3:32:24 PM EDT
[#2]
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Posted: 5/20/2020 3:46:02 PM EDT
[#3]
This is a technical forum. Take your "dupe" back to GD.
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Posted: 5/20/2020 3:57:08 PM EDT
[#4]
Quote HistoryOriginally Posted By Element94: Good. Bring it all up. #raisethetitanic! In all seriousness, it's such a monumental undertaking for such a minor reward. The deterioration of the ship has advanced so much over the last 15 years...nature doesn't need anymore help turning her into a rust stain. |
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Posted: 5/20/2020 4:39:42 PM EDT
[#5]
I dunno... A new IC-7300 is a better choice. Probably cheaper too.
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Posted: 5/20/2020 4:50:30 PM EDT
[#6]
That's pretty cool, 5KW at .6mhz... I wonder how big that antenna was.
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Posted: 5/20/2020 5:11:06 PM EDT
[#7]
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Posted: 5/21/2020 7:51:23 AM EDT
[#8]
Quote HistoryOriginally Posted By Gyprat: I dunno... A new IC-7300 is a better choice. Probably cheaper too. 
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Posted: 5/21/2020 1:31:17 PM EDT
[#9]
Quote HistoryNeat, a top-loaded / T-Top antenna. More info on them here: https://en.wikipedia.org/wiki/T-antenna
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Posted: 5/21/2020 3:05:18 PM EDT
[#10]
It will be interesting to see if there is anything left of the radio room/setup. 100+ years of sitting at the bottom of the ocean has probably done some serious damage.
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Posted: 5/21/2020 3:56:03 PM EDT
[#11]
seems like a colossal waste of time, money, and labor
....for what?.....a big coil and some leyden jars ? 
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Posted: 5/21/2020 3:59:18 PM EDT
[#12]
Quote HistoryQuoted: It will be interesting to see if there is anything left of the radio room/setup. 100+ years of sitting at the bottom of the ocean has probably done some serious damage. Actually I doubt there is much damage. Given the depth, water temp, and lack of oxygen a lot of old (read really old) shipwrecks are very well preserved. |
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Posted: 5/21/2020 5:03:56 PM EDT
[#13]
Quote HistoryQuoted: Actually I doubt there is much damage. Given the depth, water temp, and lack of oxygen a lot of old (read really old) shipwrecks are very well preserved. Artist rendering on the left:  |
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Posted: 5/21/2020 6:50:28 PM EDT
[#14]
Quote HistoryQuoted: It will be interesting to see if there is anything left of the radio room/setup. 100+ years of sitting at the bottom of the ocean has probably done some serious damage. You should see some of the stuff they dig out of the European mud from both World Wars. Sometimes being packed in mud they're protected from O2 exposure and they come out of the ground looking almost like the day they went in. |
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Posted: 5/21/2020 8:33:51 PM EDT
[#15]
International convention called the use of the 600-meter band for ship-to-shore communications, and the 300-meter band for ship-to-ship work... From the era of the misconception that longer wavelengths went further. 500kHz and 1000kHz. Amateur radio was allowed everything higher in frequency than 200 meters (aka "200 meters and down") under the theory that all those frequencies were useless for "real" radio. |
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Posted: 5/22/2020 4:09:30 PM EDT
[#16]
For those interested, the Marconi magnetic detector used in the Titanic's receiver is explained HERE.
 Detector in action:  Marconi magnetic detector demonstration |
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Posted: 5/22/2020 5:44:33 PM EDT
[#17]
Quote HistoryQuoted: I dunno... A new IC-7300 is a better choice. Probably cheaper too. good one.. There is no radio. This was before vacuum tubes were invented. It is a spark gap, A very high voltage was generated and fed to a spark gap key ( I have one ) The frequency was determined by the length of the antenna, when the gap was closed for a morse code digit, it sent a pulse to the antenna wires of a whole lot of RF frequencies, like most of them. The length of the wire resonated the spark pulse and the frequency was mostly radiated as the standing wave ( resonant ) of the antenna length with a whole bunch of harmonics. it was crude, very noisy RFI wise and dangerous by today's standards due to the high voltages and currents at the key contacts Too bad it is now illegal to transmit this way, I would love to try out my spark gap key with a real spark gap transmission. |
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Posted: 5/22/2020 6:27:25 PM EDT
[#18]
Quote HistoryQuoted: It will be interesting to see if there is anything left of the radio room/setup. 100+ years of sitting at the bottom of the ocean has probably done some serious damage. Nah. They built 'em to last back then. Dry it out and it'll fire right up. |
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Posted: 5/22/2020 6:53:10 PM EDT
[#19]
Good. NTSB can pull the data.
Some say it was a torpedo. |
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Posted: 5/22/2020 8:53:25 PM EDT
[#20]
Quote HistoryQuoted: I dunno... A new IC-7300 is a better choice. Probably cheaper too. Hold up, must've missed the 600-630 meter TX on the 7300. 
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Posted: 5/23/2020 8:44:19 PM EDT
[#21]
Quote HistoryQuoted: Hold up, must've missed the 600-630 meter TX on the 7300. Quote HistoryQuoted: Quoted: I dunno... A new IC-7300 is a better choice. Probably cheaper too. Hold up, must've missed the 600-630 meter TX on the 7300. Apparently It does transmit there. There is a mod to enable it |
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Posted: 5/25/2020 1:27:02 AM EDT
[#22]
Quote HistoryQuoted: good one.. There is no radio. This was before vacuum tubes were invented. It is a spark gap, A very high voltage was generated and fed to a spark gap key ( I have one ) The frequency was determined by the length of the antenna, when the gap was closed for a morse code digit, it sent a pulse to the antenna wires of a whole lot of RF frequencies, like most of them. The length of the wire resonated the spark pulse and the frequency was mostly radiated as the standing wave ( resonant ) of the antenna length with a whole bunch of harmonics. it was crude, very noisy RFI wise and dangerous by today's standards due to the high voltages and currents at the key contacts Too bad it is now illegal to transmit this way, I would love to try out my spark gap key with a real spark gap transmission. Quote HistoryQuoted: Quoted: I dunno... A new IC-7300 is a better choice. Probably cheaper too. good one.. There is no radio. This was before vacuum tubes were invented. It is a spark gap, A very high voltage was generated and fed to a spark gap key ( I have one ) The frequency was determined by the length of the antenna, when the gap was closed for a morse code digit, it sent a pulse to the antenna wires of a whole lot of RF frequencies, like most of them. The length of the wire resonated the spark pulse and the frequency was mostly radiated as the standing wave ( resonant ) of the antenna length with a whole bunch of harmonics. it was crude, very noisy RFI wise and dangerous by today's standards due to the high voltages and currents at the key contacts Too bad it is now illegal to transmit this way, I would love to try out my spark gap key with a real spark gap transmission. So, basically arc welding. Give it a try, why not? |
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Posted: 5/25/2020 11:37:22 AM EDT
[#23]
So on the topic of spark gap transmitters. I'm somewhat uneducated was it like ultra wideband cw? I realize it's cw but wasn't sure how center frequency was set or how wide the cw RF was radiated from center
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Posted: 5/25/2020 12:36:03 PM EDT
[#24]
The antenna was resonant on one frequency, which helped attenuate harmonics and wideband noise...somewhat.
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Posted: 5/25/2020 12:53:20 PM EDT
[#25]
Quote HistoryQuoted: So on the topic of spark gap transmitters. I'm somewhat uneducated was it like ultra wideband cw? I realize it's cw but wasn't sure how center frequency was set or how wide the cw RF was radiated from center I think they had an LC circuit on the output |
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Posted: 5/25/2020 1:24:22 PM EDT
[#26]
Quote HistoryQuoted: I think they had an LC circuit on the output Quote HistoryQuoted: Quoted: So on the topic of spark gap transmitters. I'm somewhat uneducated was it like ultra wideband cw? I realize it's cw but wasn't sure how center frequency was set or how wide the cw RF was radiated from center I think they had an LC circuit on the output the later ones did in order to decrease bandwidth and increase range the early ones did not, they relied strictly on the antenna wire to determine frequency and the bandwidth was yuuuuuge I think I may try to build one. they used batteries, some type of oscillator to create AC and a transformer to step up the voltage. I am still researching what I need to build a small one without electrocuting myself |
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Posted: 5/25/2020 1:39:46 PM EDT
[#27]
Quote HistoryQuoted: Neat, a top-loaded / T-Top antenna. More info on them here: https://en.wikipedia.org/wiki/T-antenna Interesting Wikipedia entry on the Grimeton Radio Station in Sweden, which used the same type of antenna to transmit at 17.2 KHz. They still fire the station up once a year, for commemorative purposes. |
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Posted: 5/25/2020 1:59:11 PM EDT
[#28]
Quote HistoryQuoted: the later ones did in order to decrease bandwidth and increase range the early ones did not, they relied strictly on the antenna wire to determine frequency and the bandwidth was yuuuuuge I think I may try to build one. they used batteries, some type of oscillator to create AC and a transformer to step up the voltage. I am still researching what I need to build a small one without electrocuting myself RFI monsters, not legal since the 1930's 
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Posted: 5/25/2020 2:00:52 PM EDT
[#29]
Quote HistoryQuoted: For those interested, the Marconi magnetic detector used in the Titanic's receiver is explained HERE. http://www.sparkmuseum.com/images/Marconi/MARC4.GIF Detector in action:  https://www.youtube.com/watch?v=4CAxWoKD-fwThis is even more interesting than the transmitter. 
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Posted: 5/25/2020 6:49:50 PM EDT
[#30]
Quote HistoryQuoted: RFI monsters, not legal since the 1930's Quote HistoryQuoted: Quoted: the later ones did in order to decrease bandwidth and increase range the early ones did not, they relied strictly on the antenna wire to determine frequency and the bandwidth was yuuuuuge I think I may try to build one. they used batteries, some type of oscillator to create AC and a transformer to step up the voltage. I am still researching what I need to build a small one without electrocuting myself RFI monsters, not legal since the 1930's The original type oscillator is basically a relay. The current from the battery going through the coil goes through a contact that is on a spring, the coil energizers and magnetically over comes the spring and pulls in the arm connected to the contact, when that happens the contact is no longer in contact, the current is interrupted, the coil de-energizes, the spring pulls the contact back into contact and the process repeats creating AC at the battery voltage which is applied to a transformer which outputs big voltage. the big voltage conducts through a spark gap and that spark gap is connected to wire and the RF is created like a lightning bolt creates RF, by a big spark, except this spark is 1/2 an inch or so, goes to the wire antenna and a radiated signal is created. The on off switch is the key. I think I want one It would be very easy to make one using a battery, a relay, and a transformer and a gap for a spark, but that would be cheating. I am going to have to make it from scratch to look like they did back then. |
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Posted: 5/26/2020 3:39:23 PM EDT
[#31]
Early high power transmitters used motor driven alternators to generate the low frequency signal. A rotary spark gap gave it an audible tone.
  In the CGI image of the Titanic's transmitter, the rotary spark gap can be seen on the right of the MG set. It's enclosed in a sealed box vented to the outside to get rid of the noxious fumes it created. What a rotary spark gap sounds like. In spite of the raspy tone, it's perfectly readable to anyone who knows CW.  Spark Gap Transmitter - Blue Lightning 1/2 kW ca. 1910 Style Radio |
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Posted: 5/27/2020 12:40:37 PM EDT
[#32]
Quote HistoryQuoted: Interesting Wikipedia entry on the Grimeton Radio Station in Sweden, which used the same type of antenna to transmit at 17.2 KHz. They still fire the station up once a year, for commemorative purposes. I went down that rabbit hole too and look forward to the next time they fire it up to see if I can hear it. |
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