Hi Bill
Actually those are examples ("such as") of permitted modes, and NTIA have said
they are not limiting.
Note that 2K80J2D: the 2K80 means 2.8 kHz, and the J2D means SSB suppressed
carrier with data. But
of course you can do smaller bandwidths than the limit of 2.8 kHz. Ham-RTTY is
250HJ1B when stated
in a SSB channel.
That list is stated to be an example of what is permitted.
ARRL agrees about Amateur RTTY, since they published my technical correspondence
on how to do
RTTY on 60 m in Sept 2013 QST " Set your radio and software for proper RTTY
operation." (below).
Yes you can do Amateur-RTTY on 60 m.
73
Kai, KE4PT "Correspondence" follows
------------------------------from QST Sept 2013 p65-------------------------
60-Meter RTTY
Set Your Radio and Software for Proper RTTY Operation
I read with interest the "Eclectic Technology" column by Steve Ford, WB8IMY, in
the August 2012 issue of QST (page 56) in which he describes how to operate
PSK31 on 60 m.
Here are some really easy instructions for operating traditional 170 Hz shift
RTTY at 45.5 baud while adhering to the FCC and NTIA rules for the 60 m band.
The rules state that all the permitted digital modes must be centered in the 60
m band channels. Also, to satisfy the NTIA, the radio receiver must be
configured so that an upper sideband SSB signal can be copied in case the
primary users need to tell you the channel is occupied. For RTTY, we use the
same suppressed carrier SSB channel frequencies (the frequencies that appear on
your transceiver display) that Steve lists in his column.
One simple way of generating the "ham-RTTY" data mode in the 60 m band channels
is to operate using the so-called "AFSK" method of generating the data signals.
A computer sound card generates audio tones that are fed into the transmitter
microphone or other audio input connector. With a properly adjusted SSB
transmitter, the audio tones (one at a time) produce an RF signal at the carrier
frequency plus the audio tone frequency for an upper sideband transmission. (The
RF signal would be the carrier minus the audio tone frequency for a lower
sideband transmission.) In effect, the transmitted RF output frequency shifts
between two frequencies as the audio input tones shift. The result is a
frequency shift keyed RF output --- FSK.
The following settings work well with "AFSK" RTTY. I based these instructions on
the very popular MMTTY RTTY software, but you can use the same technique with
other RTTY applications.
(1) Set the rig to upper sideband SSB or upper SSB digital mode, just like you
would for PSK31 (this keeps you consistent with the NTIA requirement that you
monitor the channel for upper sideband transmissions) with the dial set to your
chosen upper sideband suppressed carrier channel frequency.
(2) In MMTTY select the Mark frequency as 1415 Hz (in upper sideband this will
actually be the Space frequency).
(3) Set MMTTY to "Reverse" (because you are using upper sideband).
(4) Set Shift to 170 Hz and baud rate to 45.45.
This will have the effect of centering the RTTY tones at the radio dial
frequency plus 1500 Hz, with the two tones at ± 85 Hz. In other words, the Mark
and Space tones will appear dead center in the channel. The tones will be 1415
and 1585 Hz above the upper sideband SSB dial frequency.
Note that with MMTTY set to "reverse," the MMTTY tone nomenclature is not
correct. The 1415 Hz frequency is actually the Space frequency, while the Mark
frequency appears at 1415 + 170 = 1585 Hz above the channel SSB "carrier"
frequency. If your MMTTY ini file does not include "MARK=1415", you can edit the
MMTTY.INI file to add 1415 to the list, so the Mark= line looks like:
[ComboList]
Mark=2125,2000,1700,1445,1415,1275,1170,1000,915,660
You can operate with these same parameters in any other ham band where RTTY is
permitted. It will work just fine, and will be compatible with all other RTTY
users! As an added benefit you can simultaneously run Digipan software to get
its excellent frequency-calibrated waterfall display to see the other RTTY
signals. The two RTTY tones should straddle the 1500 Hz marker on the Digipan
display. For RTTY, you transmit and receive from the MMTTY window. Also, using
this method you can listen for any SSB signal on the channel and you can
transition instantly to PSK31 without changing anything on the rig.
--- Kai Siwiak, KE4PT
-------------------------------------------END----------------------------------------
On 11/25/2013 5:15 PM, Bill Turner wrote:
ORIGINAL MESSAGE: (may be snipped)
On Sun, 24 Nov 2013 23:12:16 -0500, Kai wrote:
Bill
The FCC/NTIA want you to:
(1) monitor the channel for possible upper SSB transmissions if you are to be
told to stop.
(2) The RTTY tones must be 1500 Hz +/- 85 Hz above the SSB rig dial frequency.
That implies you should operate RTTY in AFSK mode with the rif set to upper SSB
and
with tones set to 1415 and 1585 Hz.
Do you need specific details for using MMTTY that way? I had it was in QST Sept
2013,
technical correspondence.
73
Kai, KE4PT
REPLY:
You do make a good point about monitoring for SSB.
The big problem as I see it is the FCC 97.307 (14) (i) only authorizes four
modes for 60 meters:
2K80J3E (phone)
2K80J2D (data such as Pactor III)
60H0J2B (what they call RTTY which includes PSK31)
150HA1A (Morse CW)
So it seems that Baudot RTTY is allowed but only with a bandwidth of 60 Hz
or less. You might think that if a wideband mode such as Pactor III is
allowed,why not the much narrower Baudot RTTY?
I have no answer. For now I will stick to PSK31 on 60 meters.
73, Bill W6WRT
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