DS-VGPS-HSC
TECHNICAL REFERENCE MANUAL
The base of any GPS receiver is precise time measurement. In addition to the position information a
precise PPS (pulse per second) is generated by the GPS engine. This pulse is used to synchronize 80
MHz oscillators with software PLL (phase locked loop). The result is an ultra stable 80 MHz clock source
which is completely free of drift over time.
The communication to the host is provided over CAN or standard USB interface.
3.4. Functionality of the LEDs
3.4.1. Power (green)
The power LED is solid green when the DS-VGPS-HSC is in normal operation.
3.4.2. Status (red)
3.5. Mounting the aerial
The aerial supplied with the VGPS is designed to be mounted magnetically on top of the vehicle in a
horizontal plane. If the surface is not metallic, the aerial may be fixed by placing a piece of strong tape
over the top of the aerial. The positioning of the aerial is critical to the correct operation of the VGPS.
Note: For correct operation, the aerial requires a metallic subsurface with a minimal diameter of 15 cm.
This surface doesn’t have to be ferromagnetic.
The aerial picks up the signals from up to 12 satellites which are all in different places in the sky. These
satellites are not necessarily directly overhead, and can often be close to the horizon. Therefore it is best
to mount the aerial in a way that the least amount of metal obscures the view of the sky. On a domed
roof, place the aerial on the top of the dome. On an open car with a roll-over bar, place the aerial
horizontally on the highest point of the roll-over hoop and tape the wire securely to the frame. Although
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When the time source signal is missing (neither
GPS or IRIG time code signal), the device
automatically goes to flying-wheel operation. This
is indicated by inverted blinking.
