Chapter 3
Communication Ports
RUGGEDCOM RX1100
Installation Guide
24
IRIG-B Outputs
The following sections describe the PTP card in more detail:
•
Section 3.8.1, “IRIG-B Outputs”
•
Section 3.8.2, “Pulse-Per-Second (PPS) Output”
•
Section 3.8.3, “GPS Antenna Installation Recommendations”
Section 3.8.1
IRIG-B Outputs
The PTP Card supports both IRIG-B outputs in both Amplitude Modulated (AM) and Pulse Width Modulation
(PWM) formats. Specifically, for the AM output, IRIG-B122 and IRIG-B123 are supported. For the PWM output,
IRIG-B002 and IRIG-B003 are supported. Enabling of the AM and PWM outputs is done through software.
The number of IRIG-B devices that can be connected to the AM or PWM source is dependent on the cabling type
and length as well as the input impedances of the devices. Figure 16 shows a simplified circuit diagram of the
interface between the IRIG-B source and connected devices.
1
2
3
Figure 28: IRIG-B Simplified Schematic
1.
Source
2.
Cabling
3.
Device
The maximum number of devices (N) that can be connected to the source is determined by checking if the source
current (IS) required to drive the connected devices is less than the maximum drive current the source can
provide, and verifying that the load voltage (VL) the connected devices see is greater than the minimum required
voltage.
For specifications for the IRIG-B outputs, refer to
Section 4.6, “IRIG-B Output Specifications”
.
Section 3.8.2
Pulse-Per-Second (PPS) Output
The PTP card supports one Pulse-Per-Second (PPS) output. When enabled through ROX, the card outputs a 5 V
pulse every second.
