There is a book about this. Somewhere in my house it is on one of the bookcases. Some of the first cables, like across the English Channel, did not have any shield or armor or ground. Just one single conductor with a ground return.
In subsequent cables, sabotage during the placing of the cable in the ships hold was conducted by presumed employees of Marconi Wireless. I found it interesting that an onboard telegraph operator was talking to someone on shore during the entire voyage during more successful trips. The cable landing at Porthcurno, Cornwall has a nice museum about this built into a WWII bunker. Interesting to see the mirror galvanometers and Wheatstone bridge circuits that would null out interference and detect the tiny deviations in voltage. Not sure how long the time constant was for a pulse to traverse the cable but it was pretty long. Seemed like it took something like 3 minutes to transmit a character. If a character is 5 symbols then we are talking more than 30 seconds per pulse rise. From: Eric Kuhnke Sent: Friday, September 25, 2015 7:51 PM To: [email protected] Subject: Re: [AFMUG] OT undersea cable trivia http://atlantic-cable.com/Books/Whitehouse/DDC/ Adjusted for today's dollar (or pound) value, this would be a telecom disaster on the order of 60 Hudson collapsing into a pile of rubble. On Sep 25, 2015 6:30 PM, "Chuck McCown" <[email protected]> wrote: The first undersea telegraph lines were insulated with gutta percha. A plastic like plant resin. When I first started my career we had RG-8 coax cables in our system that were insulated with gutta percha. It is kinda yellowish green waxy stuff that is very similar to HDPE. Many of you also have gutta percha in your mouth. They fill your tooth with it when doing a root canal. I like to think my teeth and undersea telecom cables are related. Gives me warm fuzzys....
