[GreenKeys] do the length of stop bits affect clutch wear?

[Keith Lueck]

    On Thursday, November 22, 2018, 4:52:43 PM CST, Jim Haynes <jhhaynes at earthlink.net> wrote:  
 
 On Thu, 22 Nov 2018, Keith Lueck wrote:

> I think this has been discussed before, but does a specific length of stop
> bit save any wear and tear on the main shaft clutch?  IOW, is it possible
> that perfectly timed characters would keep the main shaft from having to
> stop, then start again?  IIRC, I believe the answer was, "no," but I'm not
> sure...  I'm wondering specifically about the 15 and 33.  

It is absolutely essential that the receiving shaft stop between 
characters.  If that were not so the receiver could never get sync
if it were a little slow or the transmitter a little fast.  That is
the whole point of start-stop synchronization - the receiver gets
resynchronized for each character.
Yes - I understand that.  I just figured with today's more accurate power line frequency and more accurate transmission electronics (baud rate controlled by a crystal) - it might be possible to send some number of characters w/o stopping the mechanism before re-synchronization was required (like at the end of a line, perhaps).  I guess you'd call it "sami-synchronous" transmission.  

Toward that end the receiving shaft always runs slightly fast, to
insure that it will have time to stop between characters.  In 5-level
machines the receiving shaft is fast enough that it can stop even if
the code is 7.00 units.  That was the Western Union standard.  7.42
was the Bell System standard, and 7.50 was standard for European
Telex.
Now, I didn't know that!  Thanks for that tidbit, Jim.  
Best, 
Keith


  
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