ARRL OO Notices for JT65 Users

Discussion in 'Working Different Modes' started by NN4F, Feb 11, 2013.

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  1. K0RGR

    K0RGR Ham Member QRZ Page

    OK, I"m still waiting to hear the theory behind the CW ID requirement. I don't see how that could be required. It's a data transmission. Next, we'll have to send CW ID's on 2.3 GHz to do 802.11.
     
  2. WA6MHZ

    WA6MHZ Ham Member QRZ Page

    I think if U ask Laura, she will tell she has FAR MORE IMPORTANT things to worry about!
     
  3. W4PG

    W4PG Super Moderator Lifetime Member 279 Volunteer Moderator Platinum Subscriber Life Member QRZ Page

    So what DOES the JT-65 waterfall tell us about overdriving audio??

    I don't know much about JT-65, but was playing around with it. Below are a couple of screen shots with "something" circled in RED. I was not hearing anything other than JT-65 signals at the time. Does this show a bad trace?? Overloaded signal??

    I noted that when no signals are transmitted, my audio input level drops to zero or minus 1 as indicated in the top left part of the screen.

    Soooooooo . . . CAN you make a judgment about the audio quality based on these traces? I can't seem to find anything specific about that question in the docs that come with the program.
     

    Attached Files:

  4. N2EY

    N2EY XML Subscriber QRZ Page

    It's not required.

    Part 97 states that all transmissions in the non-phone parts of the bands have to ID in either CW or RTTY. Part 97 also defines "RTTY" as a whole family of modes (see the appropriate paragraphs). Not just classic FSK 5 level Baudot RTTY but all sorts of "keyboard modes" like PSK31.

    There was a time when CW ID was required of RTTY stations. Some countries still require it - that's why most PSK31 software has the option, for example. But US hams can simply ID in the mode being used, if it meets the extremely broad requirements of Part 97.

    With JT65, there's a good reason to CW ID that has nothing to do with FCC. The mode can only send 13 characters at a time! The problem is, a monitoring station may read the JT65 but not the CW ID, and not realize it's there!

    The real problem is that we have a pile of new modes - almost a plethora - and some folks are still on the steep part of the learning curve.

    IMHO, this is NOT something we want to drag FCC into. Here's why:

    It used to be that the FCC limits on "data" modes were quite strict. I've been a ham so long I recall when the ONLY "RTTY" mode we were allowed was 60 wpm 5 level Baudot RTTY, with shift less than 1000 Hz. No other mode allowed - no ASCII, no 75 wpm, etc., even though those modes were common in commercial radio back-when.

    It took a bit of doing to get the FCC rules changed. When they did, we began to see new stuff like AMTOR and packet and PSK31. Of course PCs and soundcards helped. Best of all, new modes can get tried out pretty easily - just "publicly document" and meet certain rules.

    IMHO it would really be awful if FCC went back to the mindset of having to review and approve every new mode in detail before letting US hams use it. That could easily happen if there are all sorts of complaints. Worst of all, it makes us look dumb that we can't set our own standards and help each other out a little.

    73 de Jim, N2EY
     
  5. K3DCW

    K3DCW QRZ Lifetime Member #212 Volunteer Moderator Platinum Subscriber Life Member QRZ Page

    A "bad" JT65 signal will usually be wider than normal, possibly with harmonics throughout the display. The example you show are more typical of a simple "loud" signal. These can be mitigated through the judicial use of the RF input controls on your rig.

    Why is it loud? Could be power levels used. Could be the antenna used. Could simply be great props. Either way, while they look "fuzzy", the signals don't necessarily look "BAD".

    I think that's the argument being made here. Unless you can account for the signal strength, AGC action on your rig, and the relative audio levels within the FFT display in JT65-HF (which is VERY sensitive!!!), issuing an OO notice for bad signals is a tenuous ground to be standing on.


    73

    Dave
    K3DCW
     
  6. ND6M

    ND6M Ham Member QRZ Page

     
  7. N8WWM

    N8WWM Ham Member QRZ Page

    The ghost of Barney Phyfe strides the digital landscape, and it aint coming from TVLAND in HD.

    There was a certain amateur in the Toledo area who was employed as a security guard at the downtown location of a nationally known restaurant chain. This nameless ham made up parking citations on his home computer and proceeded to paper cars parked near his place of employment. Even worse, this dude carried a gun. Same mentality.
     
  8. KO3D

    KO3D Guest

    The same guy who walks around a VE session with three HTs yelling "NO TALKING!"
     
  9. WC5B

    WC5B Ham Member QRZ Page

    That sounds about right.
     
  10. KD0QNR

    KD0QNR Ham Member QRZ Page

    I just got interested in Jt65. But after reading this thread I may not do it because Im afraid if I make a mistake i'll get in trouble. I would rather not risk it.
     
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