For RTTY I’ve used AFSK via my SignaLink USB into my Kenwood TS-2000.  It has always worked fine but I was unable to take advantage of the RTTY/FSK filters in the TS-2000. When using AFSK you are in SSB mode and the tight FSK filters aren’t available. There are some adjustments you can make to try and compensate a bit both in the MMTTY application and on the radio but nothing compared to what I experienced this weekend when running FSK.

A club member that made me the serial to CW cable I used to work my first CW contest volunteered to add in a FSK circuit. With a spare 13-pin DIN plug that comes with the TS-2000 that I provided him and all the spare parts he had already, he turned it around quickly. I tried getting it working and ran into some issues and he even volunteered to come over and troubleshoot. After messing with the software we checked the cable connections and a couple of pins weren’t wired per the online circuits so a quick unsolder/solder and it was working like a champ. So many, many thanks to K2ZC for getting me to the next level of RTTY capabilities!!

I made notes of all the changes I made to MMTTY, N1MM and the TS-2000 so I can switch back as needed. The only TS-2000 change was on menu 39 and changing the FSK keying polarity to Inverse from the default setting of Normal. Everything else was just configuring MMTTY to specify the serial port I wa using for the FSK/PTT drop-down on the TX tab and the Misc Tab being set to COM+TxD (FSK). On the soundcard tab I changed the input from the SignaLink device to my audio card which has a mic/line in connection from the ACC2 cable as part of the cable that K2ZC made up. In N1MM I think the only change was on the Digital mode tab to change it from AFSK to FSK. No setup changes in the N1MM hardware configuration were required.

Now that I was transmitting FSK, I can put the TS-2000 in FSK mode and use the filters to narrow down the bandwidth. This filtering makes all the difference in the world when there are signals stacked up right on top of each other. I left it at 1000hz and dropped it down to 500hz if I couldn’t easily copy a signal. Going to 250hz made it even tighter and that was only needed a few times. I was now able to copy signals I wouldn’t have been able to do without the FSK filtering and would have had to move to a different frequency and tried later if they were still around.

I can’t really tell the difference in me transmitting other then I don’t think anyone asked me to repeat my exchange in the NA QSO Party this past weekend. It might have nothing to do with FSK vs AFSK but I don’t really know for sure. I know I didn’t have to worry about adjusting the transmit to get the power at max and still make sure the ALC didn’t kick in. One less thing to have to worry about.

The contest was primarily a local (US/Canada) contest but there were a few DX stations participating. I made a total of 340 Qs in the 10 hours you were around to operate. I logged Qs with 45 of the 50 states.  Here is the score summary:

        Band    QSOs     Pts  Sec   NA
         3.5     135     135   43    0
           7      88      88   34    0
          14     114     114   27    1
          21       3       3    1    0
       Total     340     340  105    1

            Score : 36,040

I had a nice hour of being in run mode on 80m with an average of 1 Q per minute which for me was great.  Using clusters isn’t allowed in the single op category for this contest so I only popped over to 15m once and there wasn’t much there. There might have been other times it was in better shape and I could have picked up more mults but I didn’t bother.

73,
K2DSL