sunair RT-9000C, Руководство по эксплуатации и обслуживанию, Страница: 315 / 393

Document No. 8128000560
Software Revision – N1B (07 Oct 04)
7-83
RT-9000 B
7.3.4.9 OPTIONS
7.3.4.9.1 High-Stability Reference Oscillator & Oven
If the High-Stability Reference Oscillator option is installed, additional warm-up time will be required for both
initial operation and full-specification accuracy. This option uses an Ovenized Frequency Standard. The
Frequency Standard must reach a specific internal temperature to achieve its frequency accuracy and
stability specifications. Warm-up time requirements will be influenced by both storage conditions and recent
operating history. Units stored near the low temperature specification limit or shutdown for prolonged time
periods will require considerably more warm-up time.
The operator must consider these requirements and their effect on initial performance when using this
equipment. This condition can be avoided by keeping the RT-9000 B continuously powered-up. This practice
is considered normal for equipment with High-Stability Frequency Standards. The benefits offered by this
option are available and convenient only if the unit is kept continuously powered-up.
Besides frequency accuracy and stability considerations, there are a few temporary effects that are uniquely
related to RT-9000 B Transceiver and its operation during the warm-up period. The following statements
summarize this behavior.
1. Units stored at low temperatures or powered-down for prolonged periods of time may intermittently
display ‘OVEN WARM UP’ messages for up to sixty (60) minutes after initial power-up.
2. During initial power-up, RT-9000 B operation will be inhibited and its I/O capability locked out
between two (2) and thirty (30) minutes, depending on the unit’s last use and storage conditions.
3. Inhibited and Normal operation indications will depend on the whether the optional F-9800
Preselector is present in the system and the RT-9000 B has been properly configured for its use. The
following describes these indications:
a) F-9800 Preselector Present
Immediately after power-up, and for at least two (2) minutes, all RT-9000 B operations will be
inhibited. During this period, no Front Panel control keys should be depressed or any use
attempted. After this period elapses, the Feature Menu will automatically change to the Pre-
selector Selection Menu shown in Figure 7.3.4.37. Operation at reduced accuracy will now be
possible until the Oven stabilization period elapses.
If the Front Panel ‘FAULT’ lamp is lit or warning messages are still appearing, more time
warm-up time is required. This period should not exceed 30 minutes.
b) F-9800 Preselector NOT Present
Immediately after power-up, and for at least two (2) minutes, all RT-9000 B operations will be
inhibited. During this period, no Front Panel control keys should be depressed or any use
attempted.
After this period, operation will be possible even if the ‘FAULT’ lamp is lit or warning
messages are still appearing. Operation will be possible at reduced accuracy until the
specified Oven stabilization period elapses.