Symmetricom 5071A, Operating And Programming Manual

Page: 24 / 194

Preface
xxii Operating and Programming Manual
Operating modes: There are two operating modes: Normal and Standby.
The default mode is Normal. The operating mode should never be changed
from Normal to Standby except under special circumstances. These are
described below.
PLACING THE 5071A IN STANDBY MODE WILL
CAUSE A LOSS OF TIME AND FREQUENCY ACCURACY . (See
Cautions beginning on page 25.)
1. Normal mode: The 5071A always powers up in this mode. Use this
mode for all normal operation and timekeeping.
2. Standby mode: The Standby mode is enabled through the Utility
menu and is used for two special purposes;
• Long term storage - Use Standby when the 5071A is stored more
than 3 months. (See Long-Term Storage on page 133 for more
information.)
• Service - If a failure occurs, diagnostics operate in Standby mode.
Remote operation: The remote state can only be entered via remote
command through the RS-232C port. In this state the 5071A operates
normally with the front-panel controls locked out: no changes can be made
to parameters (like 1PPS delay), and no actions can be taken via the front
panel. Status information however, can be read when the front panel is
locked. If any disallowed operations are attempted the 5071A beeps and
displays a message. Remote operation is indicated on the front-panel
display with a small lock symbol on the right-hand side.
We believe you will find the 5071A easier to use, more flexible in
adapting to your needs, and significantly more accurate and stable
than any cesium standard you have ever owned. Now, if you have not
already done so, power up the 5071A (instructions are on page 8).