[Excerpt from: https://amigan.yatho.com/SP54.pdf]

SIGNETICS SUPPORT SOFTWARE FOR USE WITH GE'S MARK III TIMESHARING SYSTEM SP54

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1. SUMMARY

... The programs are accessed through a communications terminal connected to
General Electric's Mark Ill Timesharing System via standard telephone lines.

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4. OPERATING INSTRUCTIONS

This section provides a synopsis of operating instructions for using the GE
Mark III Timesharing Service ...  For more detailed information on the
capabilities of the GE Mark III Timesharing Service, refer to the following
manuals available from General Electric's Information Services Business
Division:

1) Command System -- Mark III Foreground Reference Manual No. 3501.01J

2) Editing Commands -- Mark III Foreground Reference Manual No. 3400.01F

When using high-speed terminals (120 cps and up) or in the event of any
difficulty, contact your local General Electric Sales Office.

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A. LOGGING IN

Set the terminal to "LINE" mode.

Select the half-duplex mode, using the HALF/FULL duplex switch (if necessary).

When you hear the high-pitched tone (indicating that you have established
communication with the computer), place the telephone receiver in the modem
coupler.

NOTE: In the following examples data typed by the user is underlined to
distinguish it from data printed by the computer.

Log in as follows:

H carriage return

Depressing the carriage return key terminates all input lines.  Some General
Electric personnel recommend that four Hs, HHHH, be entered instead of one.
The timesharing system determines the speed of your terminal from the speed
at which these characters are received.

The computer will respond to your H carriage return entry with:

U#=

At this point enter your user ID (3 alphabetic characters and 5 numeric
characters) and press the carriage return:

U#= AAANNNNN

The system responds

PASSWORD
SSSSSSS

providing a blocked-out area in which you may enter your password. Type the
password on top of the blocked-out area and press the carriage return.  At
this point the system may send an informative message to your terminal.
Some user IDs are equipped with a short log-on sequence. If this is true,
the system responds with

READY

If this is not true, the system responds with

ID:

This is a request for accounting information. If you do not wish to enter
any accounting information, simply press the carriage return:

ID: carriage return

The computer will respond with:

SYSTEM:
Specify FORTRAN IV
SYSTEM: FIV

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