LF,

Before WSPR-15 came up in 2011, Markus/DF6NM developed a tool which can generate and decode WSPR-15 and other WSPR modes. We used WSPR-8 (4 times slower, +6 dB) and even WSPR-30 (16x slower, +12 dB). The program collects the data from SpectrumLab and replays it faster afterwards, and leads the output to a normal WSPR decoder. So this fast replayed data can be fed into the new WSJT-X program running in WSPR-2 mode.
I remember positive tests with Jay/W1VD

If someone is interested, i could look into the details again. I guess the program is still available. Maybe Markus want's to comment.

73, Stefan

Am 20.02.2018 17:33, schrieb Alex R7NT:

Rob,

I believe that WSPR15 is more viable on 136 at low powers (up to 1W ERP) on long QRB (compared with WSPR2) :)

It's like comparing OP8 (~WSPR2) and OP32 (~WSPR32). 

But OP8 died a few years ago on 136

73! Alex R7NT  136.73.ru

2018-02-20 15:32 GMT+03:00 Rob Renoud <[email protected]>:

Two T/A spots from Geoff, G0LUJ, last evening on 2200M at -35dB and -37dB show WSPR-15 to be a viable mode on 136 KHz.  I will continue nightly WSPR-15 transmissions for the next week or so.

Does anyone have an early release of WSJT-X with the slow JT9 modes included?  I believe that WSJT-X V. 0.95, r3243 released about 04/2013  may be one release that includes the slow JT9 modes.

73,
Rob - K3RWR