LF: Re: [rsgb-lf-group] Frequencies for JT9-Slow

[N1BUG <paul@n1bug.com>]

Andy,

The present version of SlowJT9 has a limit of 843 Hz audio frequency
for JT9-5. JT9-10 when implemented may have a 419 Hz limit.

During recent tests, some preferred to transmit around 136.6 to
136.85 to allow receiving stations to leave receivers on 136.000 and
still monitor other modes along with JT9-5. Others could not do that
and operated JT9-5 around 137.3 to 137.4.

If Rik is able to remove the audio frequency limitations I expect
this split to disappear with everyone preferring to be in the 137.3
to 137.4 area.

73,
Paul N1BUG



On 1/2/19 6:45 AM, Andy TALBOT wrote:
> I've lost track of the emails, and BS has no archive so:
> 
> What frequencies have people been using for the JT9-Slow tests.  And are
> these now sort of de-facto fixed?
> 
> I'll be coding up a PIC / GPS / DDS combination for a JT9-Slow modes beacon
> test source soon.   Freq shift / baud settings based on an early WSJT-X Ver
> 1 document found on Joe's site.
> http://physics.princeton.edu/pulsar/K1JT/WSJT-X_Users_Guide.pdf    page 21
>  viz. shift / baud rates of :
> 
> -1   12k / 6912
> -2   12k / 15360
> -5   12k / 40960
> -10 12k / 82944
> 
> a -30 version is also shown there  as 12k / 252000
> 
> 
> Andy
> www.g4jnt.com