[CQ-Contest] e: Fwd: [wsjtgroup] WSJT-X 2.1.0-rc6

[donovanf at starpower.net]

Hi Roger, 


The power available at the receiving end of 19th century transatlantic 
cables was so feeble that it couldn't possibly be detected by an undulator. 
William Thomson, later knighted as Lord Kelvin, invented the mirror 
galvanometer in 1857 for use on the first transatlantic telegraph cable. 


The syphon recorder replaced Thomson’s mirror galvanometer as the 
standard receiving instrument for submarine telegraph cables about 
ten years later. 


Good descriptions of these early submarine telegraph instruments 
are here: 


http://atlantic-cable.com/Article/Instruments/index.htm 


73 
Frank 
W3LPL 

----- Original Message -----

From: "Roger Parsons via CQ-Contest" <cq-contest at contesting.com> 
To: "Contest" <cq-contest at contesting.com>, donovanf at starpower.net 
Sent: Tuesday, June 4, 2019 8:36:03 PM 
Subject: Re: [CQ-Contest] e: Fwd: [wsjtgroup] WSJT-X 2.1.0-rc6 

Clearly so! I was not aware of this and perhaps I should have been. 

My experience was related to long underwater telegraph cables where cable capacitance and losses meant that devices using negligible power were essential. Hence the undulator, which was certainly in use for approaching 100 years. A casual internet search did not find any information on these devices, but probably it is there somewhere. 

But apart from being wrong, I am definitely right in saying that undulator tape can be read very fast indeed! 
73 RogerVE3ZI 


On Tuesday, 4 June 2019, 14:32:12 GMT-4, donovanf at starpower.net <donovanf at starpower.net> wrote: 

Zack is correct and Roger's historical knowledge needs a little work. 
This is an image of Morse's original 1844 paper tape on display in the Smithsonian: 
http://ids.si.edu/ids/deliveryService?id=NMAH-2006-10282 
Roger, this is a good place to start. The paper tape embossing instrumentused during Morse's Washington-Baltimore two way demonstration isshown in the article. It was very noisy! 
http://time.com/4307892/samuel-morse-telegraph-history 
73FrankW3LPL 


From: "Roger Parsons via CQ-Contest" <cq-contest at contesting.com> 
To: "Contest" <cq-contest at contesting.com>, "w9sz zack" <w9sz.zack at gmail.com> 
Sent: Tuesday, June 4, 2019 2:21:19 PM 
Subject: [CQ-Contest] e: Fwd: [wsjtgroup] WSJT-X 2.1.0-rc6 

Zack, W9SZ wrote: 

"The original Morse telegraph (and others) worked by imprinting the dots and 
dashes on a paper tape and then decoded by reading it. Imagine doing a 
contest that way! Then someone figured out that it was faster to learn to 
decode the messages by ear." 

I have no horse in the WSJT race, but just a little historical comment: 

The original telegraph using paper tape used an undulator. (This is a moving ink nozzle that will move up and down in response to the received signal. So there is a continuous print.) Having had to learn to read undulator tape (both Morse and cable code) at the end of an era, I can confidently say that it was possible to easily read either at 100 wpm. I think that audio reading (tone or clicks) came about because of (1) the cost and maintenance levels required for undulators at small stations and (2) undulators did not work at all well on early radio receivers. 

73 Roger 
VE3ZI 
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