indicate
the
FM reception of
realtime telemetry.
The
Synchronous Command Generator will also display sun pulse lock on its panel.
8.5.3 Tape Recorder
A simulated
PCM
data
The
stream
approximately five minutes.
from
one
of the baseband
The
equipment strings will be patched into the tape recorder. be recorded for will data time PCM
code and
Selected telemetry words from each minor frame will be printed during this period. tape will be played back and the printed telemetry words from the played-back data stream will be compared with the original data to verify correct recording.
8.5.4 Stripchart Recorder
stream will be patched into the
The strings. baseband
the
Frame
A simulated PCM data receiver in
of one Synchronizer's output will e patched into the Selectable is attached to the which Telemetry Display (STMD),
with known stripchart Recorder. Eight telemetry words
front panel. the STMD values will correctness of the data recorded on the Stripchart Recorder will be compared with the known values to verify proper recording function.
be
at selected
The
8.6
Range
The
software ranging
calibration
and
thoroughly demonstrated
on-site
acceptance
which functions
provide computation of
points will range subsystem during
factory
will following test tests. The
for
be and be
conducted during site acceptance tests.
8.6.1 Closed-Loop Ranging
The Realtime Computer, Range Tone Processor, FM Modulator, and Telemetry Receiver are configured to form an IF loop. The IF ranging calibration is initiated by the Computer and the phase counts displayed by the computer will be compared with counts displayed by the Range Tone Processor.
The delays through the RF uplink and downlink equipment will be measured during RF subsystem on-site acceptance tests. These delays and the IF loop delays will be subtracted from the total ranging delays during ranging data computation by the realtime computer.
8.6.2 Ranging System Compatibility
Ranging uplink system through the HPA will be tested with manually initiated ranging tones at the spacecraft receiver frequency (DISH or OMNI). The presence of the modulated The FM ranging tones at the HPA output will be observed. Modulator in the uplink path will be checked for correct
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