Loading ...
Sorry, an error occurred while loading the content.

1283When is a door not a door ?

Expand Messages
  • graham787
    Aug 21, 2014
    • 0 Attachment

      Following on from the difficult question

      When is a door not a door ? ....When its a JAR

      All Ham data modes that pass via SSB tx audio channel are grouped under the heading of J2D..

      How the audio is generated or decoded is of no interest other than it shares the same generic title 'Spread Spectrum' which , now covers 'all aspects' of data processing of this type , the FCC classed the test modes as J2D , just the same as Olivia , MFSK , JT65 WSPR, pactor or any other audio based system

      Nonsense based round secrecy issues are flawed , as the same program's are available to all stations, try decoding Olivia , without the correct software , not possible , it therefore must be a secret code , use any of the available packages and it decodes , therefore its not a secret code...

      So when is a mode secret and SS ?

      Ans Not when everyone has the same software and it passes via SSB sound channel


      So can we all get back to qrp dxing on the same qrg again ?

      To quote the part-97

      The FCC issued STA to test Spread Spectrum , for Ros and Chip64

      If you look up the FCC website you'll see the interesting thing about the STA is the Emission Designator classification that was used - J2D

      Modes which that have that designation are by the FCC's own definition NOT "SS emissions". J2D modes are already permitted on HF.

      This sounds like people have been doing what we have done, taken SS to mean an abbreviation for Spread Spectrum when in fact the FCC's definitions are clear that the two are not the same. J2D is not SS (SS emissions would be specified as JXX) J2D is covered under the Section 97.3 Federal definition for Data.

      As you know the FCC regulates Amateur Radio transmissions by what might be called "Content Type". The definitions for CW, Voice, Image, Data, SS etc are all in Section 97.3 at http://www.gpo.gov/fdsys/pkg/CFR-2011-title47-vol5/xml/CFR-2011-title47-vol5-sec97-3.xml

      The Data definition says: (2) Data. Telemetry, telecommand and computer communications emissions having (i) designators with A, C, D, F, G, H, J or R as the first symbol, 1 as the second symbol, and D as the third symbol; (ii) emission J2D; and (iii) emissions A1C, F1C, F2C, J2C, and J3C having an occupied bandwidth of 500 Hz or less when transmitted on an amateur service frequency below 30 MHz. Only a digital code of a type specifically authorized in this part may be transmitted.