[GreenKeys] Formats

Bob Camp ham at cq.nu
Tue May 11 22:33:59 EDT 2004


Hi

There are various mechanical gizmos that would force a CR + LF when you 
got to a certain point on the page. The obvious problem is that the 
carriage takes a couple of character times to get across the page. More 
or less there is no free lunch ...

In order to be *sure* that the CR /  LF process is done you need to 
allow at least three character times for a Teletype and my 
understanding is four or five for a Creed.

	Take Care!

		Bob Camp
		KB8TQ


On May 11, 2004, at 10:22 PM, Eric Scace K3NA wrote:

> Hmmm...   Your logic sounds right.  It's been a while since I worked 
> on this.
>
> I know for certain the CR CR LF convention was extremely common.
>
> Something sticks in my memory that there was mechanical something that 
> could be used to force a machine to turn up the platen when
> the typebox approached the left margin... but didn't do it if the 
> typebox was already at the left margin?  This was not part of the
> stuntbox -- it was elsewhere in the machine, maybe on the front right.
>
> Maybe someone else has better memory, or the real manuals at hand.
>
> -- Eric K3NA
>
>
> -----Original Message-----
> From: wa2hwj at att.net [mailto:wa2hwj at att.net]
> Sent: 2004 May 10 17:28
> To: eric at k3na.org
> Subject: RE: [GreenKeys] Formats
>
>
> Eric,
> Logically, you want your machine to LF if it gets a false CR, not the 
> other way around. Or. you might want to put an LF in the CR
> slot and a CR in the LF slot and let them both operate at the same 
> time. If I remember right, the 28 has a two-slot-wide trip arm
> for each of those functions.
> Jack WA2HWJ
>
>
>
>>    Your Kleinschmidt is very unusual, or incorrectly set up.
>>
>>    Machines with non-overline functions are normally set up to do a 
>> CR whenever
>> a LF is received... not a LF whenever a CR is
>> received.
>>
>>    The transmission of two CRs is a long-standing convention to 
>> ensure the
>> return to the start of a line, even if one CR gets
>> garbled.
>>
>> -- Eric K3NA
>>
>> -----Original Message-----
>> From: greenkeys-bounces at mailman.qth.net
>> [mailto:greenkeys-bounces at mailman.qth.net]On Behalf Of wa2hwj at att.net
>> Sent: 2004 May 10 10:12
>> To: greenkeys at mailman.qth.net
>> Subject: [GreenKeys] Formats
>>
>>
>> ZCZC
>>
>> Some TTY's have non-overline that line feeds on a CR. One of my
>> Kleinschmidts line feeds at every CR, so everything comes out
>> double-spaced (such as when I use Heavymetal). It makes more sense
>> to use LTRS as a buffer instead of several CR's.
>>
>> Jack WA2HWJ
>>
>> NNNN
>>
>>
>>>    A few minor comments:
>>>
>>> 1.  It is perfectly acceptable to end a line with:
>>>     CR CR LF FIGS FIGS
>>> The key point is to send, two times, the shift character needed to 
>>> place the
>>> machine in the proper case for the first printing
>>> character in the line.
>>>
>>> 2.  The "traditional" end of message sequence placed the machine in 
>>> letters
>> case
>>> before sending the sequence of LF and N characters,
>>> so that a case shift character was not needed before the Ns.  In the
>> historical
>>> sense, the end of message was thus:
>>>    (place machine in letters case, if not already there)
>>>    CR CR LF LF LF LF NNNN and 12 LTRS
>>> Some systems used eight LF to get the last message up to the point 
>>> where it
>>> could be immediately town off.  The 12 letters were used
>>> the form about an inch of paper tape that could be immediately 
>>> ripped from the
>>> reperforator; it also made it very easy to identify
>>> the separation between messages on a paper tape visually.
>>>
>>> 3.  We may wish to decide if we want transmissions to be "friendly" 
>>> for
>> machines
>>> with unshift-on-space (UOS).
>>>    a)  If friendly towards UOS, then one must send a FIGS before 
>>> every word
>> that
>>> begins with a figures case character.
>>>    b)  If UOS is not employed on the network, then one should be 
>>> strongly
>>> encouraged to send two FIGS when shifting into figures
>>> case, and two LTRS when shifting into letters case.  While by no 
>>> means
>>> foolproof, this improves the chances of ending in the proper
>>> case.  (It was required procedure on many US/NATO military radio 
>>> circuits.)
>>>    c)  It is not unreasonable to combine both (a) and (b); i.e., use 
>>> double
>>> shift characters whenever they are required, and send
>>> FIGS FIGS before every word that starts with a figures case 
>>> character.
>>>
>>> 4.  Start of transmission: 12 LTRS is sufficient for a minimum 
>>> sequence to
>> power
>>> up receiving machines.
>>>
>>> 5.  Do we want to encourage people to start using the start of 
>>> message
>> sequence
>>> discussed earlier?  That was twelve LTRS five SP two
>>> CR LF and then two LTRS/FIGS?  It's a good habit to form early if we 
>>> are going
>>> to employ the selective calling procedures.
>>>
>>> 6.  Should our "welcome message" summarize the selective calling 
>>> procedures?
>>> Here is a suggestion:
>>> SOME STATIONS ON THIS NET IMPLEMENT SELECTIVE CALLING PROCEDURES.  
>>> FOR
>>> COMPATIBILITY, TRANSMISSIONS OF THE FOLLOWING FORMAT ARE
>>> STRONGLY ENCOURAGED:
>>>
>>>    12 (LTRS)  5 (SP)  CR CR LF AND EITHER 2 LTRS OR FIGS AS 
>>> APPROPRIATE
>>>    (SELECTIVE CALLING SEQUENCE - SEE BELOW)  CR CR LF
>>>    TEXT OF MESSAGE, ENDING IN LETTERS CASE.
>>>    CR CR  4 (LF)  NNNN  12 (LTRS)
>>>
>>> THE SELECTIVE CALLING SEQUENCE IS ONE OR MORE STATION SELECTION CODES
>> SEPARATED
>>> BY SPACES, FOLLOWED BY "DE" AND YOUR FULL CALLSIGN.
>>> THE STATION SELECTION CODE IS THE LAST FOUR CHARACTERS OF THE 
>>> CALLSIGN OF THE
>>> DESIRED RECEIPIENT.  FOR EXAMPLE, TO SEND A MESSAGE TO
>>> THIS STATION FROM K3NA, THE MESSAGE WOULD BEGIN:
>>>
>>>    12 (LTRS)  5 (SP)  CR CR LF  2 (FIGS)
>>>    4EEG DE K3NA  CR CR LF
>>>    -- TEXT OF MESSAGE --
>>>    CR CR  4 (LF)  NNNN  12 (LTRS)
>>>
>>> TO SEND A MESSAGE TO ALL STATIONS, USE ZCZC AS THE STATION SELECTION 
>>> CODE:
>>>
>>>    12 (LTRS)  5 (SP)  CR CR LF  2 (FIGS)
>>>    ZCZC DE K4EEG  CR CR LF
>>>    -- TEXT OF MESSAGE --
>>>    CR CR  4 (LF)  NNNN  12 (LTRS)
>>>
>>> I hope this helps.
>>>
>>>    -- Eric K3NA
>>>
>>>
>>> -----Original Message-----
>>> From: Roy Norris [mailto:Rnorris at charter.net]
>>> Sent: 2004 May 8 23:42
>>> To: William N. Carver; Bill Henry; Bob Camp; David Ross; Don and 
>>> Diana
>>> Cunningham; Don Robert House; Eric Scace K3NA; Frederick A
>>> Sell; Gary Chatters; George B. Hutchison w7tty; Gerry Block; gil 
>>> smith;
>>> greenkeys at mailman.qth.net; hsvham; Jack Hart; JerryL;
>>> jhaynes at alumni.uark.edu; John Burch; John Lawson; John Parker-KE4GR; 
>>> Marvin
>>> Collins W6OQI; Richard Gillingham; Robert Downs; Stan
>>> Wilson; telegrapher at att.net; Tom Elmore; tony j. podrasky
>>> Subject: STatus of HoffNet on 10.137300 (mark)/10.137130 (space)
>>>
>>> [...snip...]
>>>
>>> ALL STATIONS, REGARDLESS OF TYPE OF EQUIPMENT ARE WELCOME.
>>> THIS NET ENCOURAGES AND PROMOTES THE USE OF MECHANICAL
>>> TELETYPE EQUIPMENT. TO ACCOMODATE TELETYPE MACHINES OF
>>> VARRIOUS VINTAGE, ALL PARTICIPANTS ARE REQUESTED TO END
>>> EACH LINE OF TRANSMITTED TEXT WITH THE SEQUENCE:
>>>
>>>          (CR)(CR)(LF)(LTRS)(LTRS)
>>>
>>> ALL TRANSMISSIONS SHOULD BEGIN WITH:
>>>
>>>       20 (LTRS) CHARACTERS (CR)(CR)(LF)(LTRS)(LTRS)
>>>
>>> AND ALL TRANSMISSIONS SHOULD END WITH:
>>>
>>>     (CR)(CR)(LF)(LF)(LTRS)(LTRS) NNNN
>>>
>>> [...snip...]
>>>
>>>
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>
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