Specifications

3-88 888-2857-001 5/9/13
WARNING: Disconnect primary power prior to servicing.
Section 3 Operation
Platinum VAX-C Series
32.768MHz (DAB
modulation)
Green = OK, Red = fault. The 32.768MHz Clock originates on the DAB
Input Option board and is routed to the Precision Frequency Reference
Unit (PFRU) where it is used as the IF PLL Reference. The IF PLL output
of the PFRU (labeled DAC Clock on the PFRU) is used on the Signal
Processing Board to produce clocks for the IF DAC and IF ADC, as well
as other various system clocks. An IF PLL Reference frequency of
32.768MHz is used for DAB modulation.
54 MHz Green = OK, Red = fault. This is an internal clock used to synchronize the RF
PLL in the Precise Frequency Reference Unit (PFRU). Non-DAB modulation
formats will use either a 10MHz or 54MHz reference for the IF PLL
10 MHz Green = OK, Red = fault. This is an internal clock used to synchronize the RF
PLL in the Precise Frequency Reference Unit (PFRU). Non-DAB modulation
formats will use either a 10MHz or 54MHz reference for the IF PLL
PLL Status (LO) is Local Oscillator.
RF (LO) PLL Lock Green = OK, Red = fault. This reference output from this circuit is used
by the up converter to set the exciter output to the correct frequency and
is used by the down converter to heterodyne the RF output samples back
to the IF frequency.
IF (LO) PLL Lock Green = OK, Red = fault. This PLL output is used as a reference by the
FPGA Modulator, Digital Precorrector, and Digital to Analog Converter
(DAC) to generate the to produce the 140 MHz analog IF output from the
signal processor board.
IF PLL Ref This indicates the reference frequency used by the IF local oscillator.
GPS
Power Supply Green = OK, Red = fault
# Sat. Detected The transmitter needs to detect a minimum of three satellites for GPS
lock and possible range.
Satellite Time Clock time-of-day
Latitude N yy degrees yy.yyy minutes
Longitude W yy degrees yy.yyy minutes
Altitude yyyy.yyy meters
NOTE: Time, Latitude, Longitude, and Altitude indications appear when the internal GPS receiver is locked
to three or more satellites.
Table 3-59 Xmtr Home> Exciter Home> Status >PFRU Status