[GreenKeys] Teletype 14 ex Australia (long)

[Larry]

List,

Many thanks to Jack, Eric and Alex for answering my queries about the
Teletype Model 14 (walking head). Thanks also to Larry in Perth for
sending this on to you.

(This text accompanies images which can be viewed at
http://home.iprimus.com.au/oseagram/youl.html )

I have no idea why this machine came to these shores, except that during
the early 1950s the Post Office (telegraph operator) was designing an
automatic telegraph switching system and I have heard that a number of
manufacturers sent machines here (we had no local industry) in the hope
of winning the contract. As it happened Siemens equipment from Germany
was used, so other models were not used. 

Although this machine had been in the Telstra (phone company) collection
in Adelaide it had presumably been in the hands of some private owner as
some of the wiring had been 'modified' in a totally unprofessional way.
Nevertheless I was able to trace enough to enable me to get the machine
working satisfactorily. Just one query- the cover opening at the front
is rather large, but there is no sign of any glass or Perspex ever being
fitted, which is unlikely as it is desirable to keep dust out, and noise
in. Can anyone offer any explanation?

I have further slightly modified the wiring and connected this machine
to 4 relays. The result is that it operates much like the Siemens 15a
R/Ts mentioned below. When a signal is received (preferably Ltrs Ltrs)
the motor starts. When the + sign is received, the tape transmission
commences, ending when the walking head reaches the punch block. Further
transmission will only occur when a further + is received. Motor stops
automatically about 15 seconds after the last character is received or
sent. 

The machine operates reliably except that the rod which moves forward
under tape for printing the 'upper case' occasionally fails to function,
resulting in the + sign not being recognised for the commencement of
tape transmission. I'll look into it soon.  
I know of only 4 teleprinter collectors in this country who have samples
of most if not all 5 unit code machines used here in the post office,
and some also have ex military machines. Also there are two museums with
full post office collections. Additionally there are a few museums and
individuals with just one or two machines. We can use our machines to
communicate over the phone lines using modems and interfaces.

Some of us are interested in switching systems used in other countries.
Although the 'torn tape' method has been mentioned we have heard that
our automatic system TRESS (Teleprinter REperforator Switching System)
was based on an American system. We would thus be very interested to
learn of any of your systems and in which cities they were known to
exist. Also, Western Union advertises themselves here as providing Money
Transfer services. Do they still operate a telegram service, and if so
what method of transmission do they use? I would expect either computer
or Fax.

This briefly is the TRESS system. It was decided to use equipment from
Siemens Germany, and from late 1959 just over 700 post offices, both
suburban and country, were connected, ending over 100 years of Morse
Code for telegrams. The Central Telegraph Office in 5 Capital Cities was
the switching centre for each state. Initially telegrams for other
states were switched manually at the CTO but a few years later, all
telegrams moved from office of origin to destination automatically.
Australia's population at this time was probably around 12 million. 

Most post offices were 'Simplex Outstations'. They had one teleprinter,
either a Creed or Teletype 15 which was used for transmitting and
receiving. When a telegram was to be sent, the operator pressed the
Carriage Return key. Automatically GA would be received if he was
connected to a Siemens 15a reperforator/transmitter in the CTO. If none
were available, OCC would be received (Occupied) and try again. 25
offices shared 10 R/Ts. After GA he transmitted Ltrs Space followed by
the three letter routing code. At the end of the first line of the
preamble he sent the = sign. This disconnected the Number Bulletin
Printer (actually a TT15) which kept a record of all first lines on the
suite of 10 R/Ts. At the end of the telegram he sent + (Figs Z Ltrs we
called it). This told the R/T to send the telegram to its destination
and break his connection to the RT, and resulted in ROK (received OK)
being transmitted back.. If the distant machine were already in use, the
equipment would 'Camp' until line was free. Thus the transmitting office
was not concerned if the distant office were a busy one. 

Busy offices were Duplex, having one machine for receiving, another for
sending. This latter was permanently connected to a RT so GA was not
received. 

Incoming messages were automatically numbered during the switching
process. Numerals for this, GA ,ROK, and any other numbers or letters
required were created on an electro-mechanical character generator. At
the end of the day a message, routed to yourself, was transmitted
showing the numbers of the last telegrams sent and received. If this
tallied with records in the CTO the traffic officer there allowed your
message to return to your office, and you dashed out the door before
another message came from states in later time zones!

The Telex network commenced in 1955. Switching was manual, and machines
used were Teletype 15s. Prior to automation in 1966, Siemens M100 were
installed in subscribers' premises. These had the important Answer-back
function. From 1975 electronic Sagems from France were purchased,
initially the TX20, later the TX 35 and finally the TX35E. These Sagems
replaced M100s, some of which went into Post offices replacing the
Creeds and Teletypes. The Telex exchange was Crossbar similar to those
used for telephones, but it was a network isolated from the phone
system. Unlike the telegram network, if a distant machine were busy, OCC
would be received and you would have to try again.

Today there are less than 300 Telex subscribers and switching is done
via the normal phone system, but a secret form of modem is used so that
nobody can hack into a Telex message. The telegram service ended in the
late 1980s. Factors were falling traffic as more and more families had
phones installed, long distance self-dialled phone calls became cheaper,
while the split of the Post Office and Telegram/Telephone services
assisted the end.

I look forward to hearing, via Larry, oseagram at iprimus dot com dot au
from anyone who can answer any of my queries =

Richard Youl, Telstra Museum Brisbane Queensland Australia