[RTTY] ARRL attack on current RTTY users

[Kok Chen]

On Nov 20, 2013, at 7:20 PM, Joe Subich, W4TV wrote:

> The entire problem with this argument is that 2200 Hz or 2800 Hz is
> not what the Commission *intended* when the current regulations were
> written.  The *intent* of the 300 baud regulations were to keep the
> occupied bandwidth consistent with other narrow band modes - e.g.,
> CW and 170 Hz shift RTTY.  

Unfortunately, none of the current Commissioners will know that.  (Unless we can point to some old documentation which they can look up.)

The same holds true for 97.307(f) -- amateurs were originally only allowed a fixed FSK shift of 850 Hz.  This was later changed in 1956 to "less than 900 Hz" to allow the use of 170 Hz shift in addition to 850 Hz, while allowing equipment inaccuracy from exact 850 Hz shifts.  Later, it was again changed to 1000 Hz shift.  Shifts that are wider was never allowed.  Again, most likely to conserve spectrum.

When you guys send in your comments, please keep in mind that we should keep the scope to what is being proposed by the ARRL.

Thus, stating something like "it does not address interference by automatic stations" is probably outside the scope of the ARRL proposal, while a statement like "allowing wider bandwidths will exacerbate the problem of interference by automatic station" might just fall within the scope.

(BTW, in their press release, the ARRL admits that Pactor 4 is illegal to use today on the ham bands due to symbol rate limits (not because it is encrypted!).  By unlimiting the symbol rate, Pactor 4 could become legal -- but we probably cannot state it directly, since the FCC probably don't regard Pactor 4 to be as nefarious as some of us do).

By the way, if they stop limiting symbol rates, 97.307(f) will no longer limit the bandwidth of even a simple binary FSK signal.  I can for example transmit using 1 kHz shift and 2000 bits per second, thereby occupying more than 3 kHz of bandwidth.  So, the original intent of limiting spectrum use that was created by 97.307(f) is completely negated by allowing symbol rate to be arbitrary.

I am sure there are lots of other inconsistencies we can point the Commission to.  Time to hit the Part 97 book, guys :-).

73
Chen, W7AY