Editing DATV TX Tutorial (section)

== 2. Configure GNU Radio and SimTX ==
# Open the supplied <code>.grc</code> flowgraph in GNU Radio Companion.
# Open its '''File Source''' block and select the converted <code>.ts</code> file. A File Source reads the video; a File Sink writes an output file.
# Check the flowgraph's '''TCP Sink'''. In the illustrated setup it is a client connecting to <code>127.0.0.1</code>, port <code>7355</code>.
# In SimTX, use '''Presets''' > '''Load Preset File...''' to load the supplied <code>.stxpreset</code>.
# Review the preset's station, frequency, power, and antenna. Confirm '''GNU Radio IQ''' is selected, its IQ Port matches the TCP Sink, and the expected sample rate matches the flowgraph.

[[File:TX1.png|thumb|center|1000px|alt=GNU Radio DVB-S2 flowgraph with File Source, coding blocks, filter, and TCP Sink to localhost port 7355.|The original flowgraph illustration. It shows a 200000 samples/s output, 100000 symbols/s, QPSK, and code rate 3/4. Current downloaded files should be checked rather than assumed identical.]]