R&S^®GPS129 GPS Receiver

Front panel

Five LEDs at the front panel indicate the status of the unit:

• The POWER LED indicates that the unit is switched on
• The FREQUENCY LED indicates that the unit has reached its operating parameters and that the accuracy of the frequency outputs is 10-9
• The LOCK LED is turned on after power-up when the receiver has acquired at least four sat-ellite signals and has computed its position; the LED is turned off when the accuracy of the out-put frequencies is reached
• The ANTENNA LED indicates a fault in the an-tenna or the antenna cable
• The ERROR LED indicates that the unit is not yet ready to operate, either because it is still booting or does not receive a satellite signal

The FORCE BOOT key forces the receiver into the boot mode. This may be necessary if the satellite data in the memory is too old or if the receiver posi-tion has changed by some hundred kilometers since the last operation.

Rear panel

All interfaces of the GPS receiver are located on the rear panel as shown in the figure above:

• COM0
  Serial RS-232-C interface providing position and time information and allowing the unit to be controlled remotely
• COM1
  Serial RS-232-C interface providing time information
• TIME CAPTURE / PULSE OUTPUT
  Special TTL inputs for storing time stamps and two TTL outputs providing pulses every second on the second or every minute on the minute
• 2.048 MHz
  Output for a precise 2.048 MHz reference frequency
• 2.048 MHz SWITCHED
  Output for a precise 2.048 MHz reference frequency that is switched on when the specified accuracy has been reached
• 10 MHz
  Output for a precise 10 MHz reference frequency
• 10 MHz SWITCHED
  Output for a precise 10 MHz reference frequency that is switched on when the specified accuracy has been reached
• ANTENNA
  RF input for connecting the GPS antenna
• Power supply input