Model E8 Series Operation Manual MODEL E8 SERIES GPS Timing & Frequency Standard USER’S HANDBOOK Quartzlock UK Ltd Gothic, Plymouth Road, Totnes, Devon TQ9 5LH, England. Tel: Fax: Web: E-mail: +44 (0) 1803 862062 +44 (0) 1803 867962 www.quartzlock.com quartzlock@quartzlock.
Model E8 Series Operation Manual Contents Safety Considerations.......................................................................................................... 3 Voltage, Frequency and Power Characteristics ................................................................... 4 Environmental Conditions .................................................................................................... 4 Replaceable Fusing Characteristics .............................................................
Model E8 Series Operation Manual Safety Considerations General This product and related documentation must be reviewed for familiarisation before operation. If the equipment is used in a manner not specified by the manufacturer, the protection provided by the instrument may be impaired. Before Applying Power Verify that the product is set to match the available line voltage and the correct fuse is installed. Before Cleaning Disconnect the product from operating power before cleaning.
Model E8 Series Operation Manual For continued protections against fire, replace the line fuse(s) with fuses of the same current rating and type (for example, normal blow time delay). Do not use repaired fuses of short-circuited fuse holders.
Model E8 Series Operation Manual E8 Series GPS Timing & Frequency Reference Introduction The GPS clock is shipped ready for operation. No adjustments are needed to have a 10MHz frequency reference and 1 pulse per second time reference within 20 minutes of initial switch on. The status of the GPS lock is shown on four LEDs on the front panel. For more information as to satellite signal strengths, etc, a computer with RS232 may be connected to the interface.
Model E8 Series Operation Manual Interface and programming The unit has one RS232 compatible interface. This is shared between the GPS receiver and the microcontroller that locks the 10MHz output to the GPS signal. On Initial switch on the interface is connected to the microcontroller. If no valid interface code is received within 30 seconds, the interface switches over to the GPS receiver.
Model E8 Series Operation Manual Microcontroller Interface The microcontroller interface allows setup and debug of the digital phase lock loop which locks the 20MHz reference oscillator to the GPS receiver. The list of control codes is given in an appendix. The only user adjustable parameter is the PLL bandwidth, which is accessed with command "UA". The band width has been factory set to optimum for the E8-X (TCXO) and the E8-Y (OCXO).
Model E8 Series Operation Manual Specifications OUTPUTS: Sine wave, 10MHz, 12dBm ± 2dBm into 50ohms Harmonics < -50dBc Spurii <-75dBc TTL, 3.
Model E8 Series Operation Manual Phase Noise E8-X 1Hz 10Hz 100Hz 1 kHz 10 kHz -60dBc -90dBc -115dBc -130dBc -140dBc WARMUP < 15 minutes to specified accuracy E8 Series A5 Manual 9 October 2008 Page 9 of 12
Model E8 Series Operation Manual Appendix A Board set up Links SP1 Leave open circuit, Used to upload new firmware to the CW25 GPS module. SP2 Leave open circuit for 3.3V antenna power. Link (default) for 5V antenna power. SP3 Link only when external clock version of the CW25 is used. SP4 Leave open circuit when U5 (enhanced voltage reference) is used. Link when U5 is not fitted to board. JP1 & JP3 fit both jumpers with shorting links for normal operation.
Model E8 Series Operation Manual Appendix B RS232 control codes (all values following command or returned from the microcontroller are hexadecimal) * = backed up in EEPROM UA User adjust UA? Returns user parameters aa bbbb * aa is bandwidth control: bits set: * bbbb is clock registers 3 and 4 (elapsed time) UABaa OS bit0, 1, 2: bandwidth (0 to 7) Write new bandwidth control byte Overall Status OS? Returns overall status bytes: aa bb cccc aa is test status byte: Bits set: bit0, 1, 2: bit3: bit4:
Model E8 Series Operation Manual PL Phase lock loop PL? Returns current status of PLL aaaa bbbb cccccccc dddd eeee * PD aaaa bbbb cccccccc dddd eeee last value of I sample (filtered), 2s complement, 16 bit last value of Q sample (filtered), 2s complement 16 bit last value of PLL integrator (32 bit integer) Coarse tune DAC 16 bit integer Fine tune DAC 16 bit integer PLIcccccccc Write new PLL integrator PLCdddd Write new coarse tune DAC PLFeeee Write new fine tune DAC PL+ Enter command PL? into r
