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Itty bitty bits of text for the gopher hole:

* Update on iridium fun : Turns out that a lot of the glitchy audio was due to the fact that when you don't filter out
the individual data streams, you end up with interleaved packets, so when multiple calls are going on at the same time,
you're hearing bits of all of them mixed together. As it turns out, iridium-toolkit comes with a script to split the
streams - so to speak - it just wasn't mentioned or documented anywhere - thus, currently I am decoding voice like this:

#!/bin/bash
OD=$PWD
ITK=~/src/iridium-toolkit
export PATH="${PWD}:${ITK}:${PATH}"
mkdir -p voice
grep "^VOC" output.parsed > voice/output.voc
pushd voice
python2 ${ITK}/voc-cluster.py output.voc
for PARSED_FILE in *.parsed; do
    echo "${PARSED_FILE}"
    BASE_NAME=$(basename ${PARSED_FILE} .parsed)
    python2 ${ITK}/bits_to_dfs.py ${PARSED_FILE} ${BASE_NAME}.dfs
    $ITK/ambe_emu/ambe -w ${BASE_NAME}.dfs
    TMPFILE=$(mktemp).wav
    sox ${BASE_NAME}.wav ${TMPFILE} silence -l 1 0.1 0.3% -1 2.0 0.3%
    cp ${TMPFILE} ${BASE_NAME}.wav
    rm ${TMPFILE}
done
popd

This produces a separate wav file for each call - much better!


* In other news - I have received an airspy sdr - which has a 10MHz bandwidth which happens to be the exact
  width of the iridium spectrum - nice - tiny review:
     - compared to the rtl-sdr, the extra bandwidth is very nice and welcome, especially for satcom.
     - The snr of the airspy seems to be much better - signals stand out better from the noise.
     - However, compared to the rtl-sdr.com dongle, it also seems to be more sensitive to overloading.
       I am getting quite a bit of fm-broadcast interference all over the band with the airspy, so a 
       broadcast filter might be a good idea - moreover I am also seeing a ton of USB signal noise, which 
       might be more tricky to block.

* In other other news - I should be receiving an USRP2 friday! this should be interesting, then I can compare
  how a "real" sdr compares ;)


Since I am currently (and perhaps fittingly given current world afairs) am rewatching the prisoner, I will part with the follow
ing:

                  ---                             
                  ---                             
                 ---                              
       -       ----      ----                     
      ---      ---     -----                      
      ---    -----   ------                       
     ---     -----------                          
     ---    ----------                            
    ----   ----------                             
    ----   ---------                              
    ----- ----------                              
     --------------         --                    
      -------------- ----------                   
       ---------------------------                
       -----------------------------              
       ---------------           ----             
       ---------------            ---             
      ----------------   B e   S e e i n g   Y o u
      -----------------            ----┃          
      -------------------        ------           
     ----------------------   --------            
    ---------------------------------             
   --------------------------------               
   ----------------------------                   
  ---------------------------                     
  -------------------------                       
  ----------------------                          
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       -------