Symmetricom TM7000, Руководство пользователя

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CHAPTER ONE
1.2 PURPOSE OF EQUIPMENT
The TymMachine performs two basic functions. First, it operates as a Time Code Generator
using an internal 10MHz oscillator, or optionally using an external frequency input (1-10MHz)
as its time base. If the SYNC-GEN feature is utilized, the unit can function as a Synchronized
Time Code Generator, synchronizing the generated outputs to an input code. Secondly, it
operates as a Translator using an input Serial Time Code as a time base. With the addition of a
double-wide option assembly, the TCG/T is also usable as a Tape Search System.
When used as a Generator, the 10MHZ oscillator is divided down to 1PPS. This divider is called
the minor time counter. The 1PPS is further divided and the count permuted so as to generate
BCD Time-of-Year in seconds, minutes, hours, and days. This divider is called the major time
counter. The terms from the major time counter are decoded into decimal form and used to drive
a LED Display. The initial time count must be manually preset into the instrument. The
Generator operation is continuous even during operation of the Translator. See Chapter Four,
Theory of Operation, in this User’s Guide for a more detailed description of the Generator.
The TymMachine Translator relies upon an input Serial Time Code for its time base. This code
is typically a member of the IRIG family. The carrier frequency of the time code is used for the
clock and the time information is automatically set into the major time counter of the Translator.
Chapter Four, Theory of Operation, in this User’s Guide gives a more detailed description of the
Translator.
The terms derived from both the major and minor time counters of the Generator and Translator
are also used to drive option circuits which develop Serial Time Codes, Parallel Outputs, and
Pulse Trains, etc.
In addition to the basic IRIG B generator, the TM7000 contains a Multi-Encoder to generate
additional time codes, an RS-232 I/O, and an RS-232 Talker.
1.3 PHYSICAL
DESCRIPTION
The TymMachine is constructed in a 1¾ inch package requiring a minimum 19 inch rack
mounting space. A decimal (LED) display, located on the front panel, shows either generated
time or translated time, depending on the mode of operation. The LCD Display along with the
switches are used to set-up and control the TCG/T. All operating controls, with the exception of
the POWER switch, are located on the front panel. The basic and optional plug-in assemblies
may have switches or jumpers to set them up in specified configurations.
Refer to the Front View of the TM7000 (Figure 1.3.1) and the Rear View of the TM7000 (Figure
1.3.2) on the next page.
1-2 TM7000 TymMachine TCG/T (Rev D) Symmetricom, Inc.