Novatel DL-V3 user manual External Oscillator, Occupation Time LEDs, Baseline Length LED Color

Chapter 2 Installation and Setup

Occupation Time

The LED that is glowing green corresponds to the DL-V3’s occupation time gauge. The occupation time LEDs provide an indication of whether sufficient data has been collected for successfully post processing data for the indicated baseline. The LED that appears corresponds to the baseline length that you can process your data to, where the first LED to the left is #1. The occupation time gauge has the following values from left to right, see Table 9:

Table 9: Occupation Time LEDs

LED#

Baseline

Length

(km)

LED Color

1

2

3

4

5

≤ 5	Green
> 5	Green
≤ 10
> 10	Green
≤ 15
> 15	Green
≤ 20
≥ 20	Green

2.2.4External Oscillator

For certain applications requiring greater precision than what is possible using the on-board 20 MHz, voltage-controlled, temperature-compensated crystal oscillator (VCTCXO), you may wish to connect the DL-V3 to an external, high-stability oscillator. The external oscillator can be either 5 MHz or 10 MHz.

Operation consists of connecting a cable from the external oscillator to the DL-V3’s BNC external oscillator port, labelled EXT OSC on the back of the DL-V3. See Figure 14 below. The receiver does not have to be powered down during this procedure.

Figure 14: External Oscillator Port

Once the external oscillator has been installed, the EXTERNALCLOCK command (refer to the OEMV Family Firmware Reference Manual) must be issued to define the clock model (for example, cesium, rubidium or ovenized crystal). If the input clock rate is 5 MHz, the EXTERNALCLOCK command must be issued to change the 10 MHz default rate.

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