Split RTTY Operation

Doug Hall

I'm new to SmartSDR and have been having a blast with my 6300. Best QSK I have used in a long, long time.

One area where this radio differs is in chasing DX on RTTY using split operation. After limited testing I've found that running two instances of MMTTY, one for each slice (the second instance installed in a separate directory) works just fine. (You have to disable most of the unused DAX channels first since MMTTY barfs over having that many sound cards.) Configure the first instance of MMTTY to use DAX RX1/TX1 and the second instance to use DAX RX2/TX2. Configure a PTT COM port for each one, and enable DAX for each slice. This lets me copy the DX on slice 1 and use the FlexControl to slide the 2nd slice around in the pileup with copy in its own MMTTY window. Select a 300 Hz filter, save a profile, and off you go.

On my wish list is a feature to make SmartSDR aware of the offset in digital modes, just as it is in CW. Without this it's an exercise in frustration trying to click-tune RTTY unless I resort to XIT/RIT hacks. Fortunately the FlexControl is better anyway as far as I'm concerned.

I'm also investigating whether the narrow filters in DIGL have the same ultimate rejection as in other modes. MMTTY's display shows some stuff coming up outside the filter passband, but that may be an MMTTY issue. I need to hook up the signal generator and see if that's the case.

I am having a blast with the 6300. I can't wait for the next DXpedition that operates RTTY.

73,
Doug K4DSP

k0eoo

Hi Doug, I believe FRS is working on adding such capability to SSDR....  There have been many requests for RTTY support from the SSDR community....

W6NEK

Hi Doug,
I use the same setup on RTTY as you do (using two instances of MMTTY). I totally agree that it should be mandatory that SmartSDR have settings for digital mode offsets. Once the correct offset is applied, tuning in a RTTY signal would be as simple as clicking on the "Mark" tone for fast accurate RTTY decoding and correct frequency display. (maybe in release 1.4 ???).

However, one very nice feature of the FLEX is being able to select independent sidebands for each Slice while in digital mode. For example, the E30FB DXpedition is currently using a very weird split on RTTY. They are transmitting using RTTY upper sideband (DIGU) and listening to the pileup on RTTY lower sideband ( DIGL). There are not many transceivers that allow independent sideband selection on VFO A and VFO B. On my K3 I have to keep pressing the ALT key to switch between upper and lower sideband as the setting applies to both Main and Sub VFO's. With the FLEX it's as simple as setting Slice "A" to DIGU and Slice "B" to DIGL. Doesn't get any easier then that!

My FLEX can be both frustrating and a joy all at the same time while using the same mode. Yet, despite the short comings, I really love this FLEX!    

73,
Frank - W6NEK