++++++++++++++++++++ From: "John-Morrow" To: , Subject: Re: [Elecraft] RTTY Operations Date: Thu, 30 Jan 2003 11:46:01 -0000 > Hey folks, anyone have any ideas as to how to properly set up filters for RTTY? Filter settings for KSB2 data are for 1000 Hz tone --- RTTY uses 2295-2125 Hz tones .... would not appear to fit if FL3 and/or FL4 are tightened to 750 to 500 Hz . Thanks .... Mike KG4MTN I have set my K2 (SN3022) to operate with the Reg1 tones of 1275/1445 Hz. At 400Hz bandwith the IF centre frequency was measured at 4913.7kHz. So I required a BFO range 4912.34-4915.06. After a lot of help from Gary and a set of new BFO crystals I got to the required range by changing C173 to 680pF and C174 to 330pF. This is quite a large departure from the 'design' values but seem to work very well. I have not noticed any signs of drift on either cw or rtty. In recent posts it was mentioned that a 4.7pf capacitor connected between the junction L33 and BFO crystals ground will give the required range but I have not yet experimented with that. I think it may be impossible to set the BFO frequencies for Reg1 tones of 2215/2295 Hz. You could get them set for rtty on some bands, say 21M and up and for rtty inverted on the lower bands. But you'd have to remember to change the settings on the TU when changing bands. Using 'Spectogram' set markers for the tones you wish to use and adjust the width/bfo frequencies so that the markers are centred symetrically within the passband. I set FL3 to 700 Hz for general use and FL4 to 375 Hz for contests. These are 6dB settings using Spectrogram. My K2 reads these as 0.77 and 0.66 respectively. 73 es gl John Morrow GI4KSH ++++++++++++++++++ From: "John-Morrow" To: "John-Morrow" , , Subject: Re: [Elecraft] RTTY Operations Date: Thu, 30 Jan 2003 12:00:13 -0000 > for Reg1 tones of 2215/2295 Hz. This should of course read as Reg 2 !! 73 es gl John Morrow Gi4ksh ++++++++++++++++++ Date: Thu, 30 Jan 2003 12:50:05 -0500 From: Steve Holton Subject: Re: [Elecraft] K2 and RTTY-settings ? To: elecraft at mailman.qth.net >Over the weekend I successfully managed my first RTTY QSO's during BARTG >RTTY Contest. >I used MMTTY with standard setup (Mark 2115 Hz and Shift 170Hz) You can also use lower frequencies for mark and space with MMTTY for example: Mark 2000, 1700, 1445, 1275, 1170, 1000 all with shift 170 1000 and 1170 aren't recommended due to harmonic considerations, 2000 or 1700 or possibly 1445 probably will bring you in range in all bands This can avoid the problems you had with using reverse on some bands which forces your "listeners" to receive you reversed. The MMTTY documentation makes this appear not to be possible, but it is if you set the "Ham Default" on: Option (O) -> Setup MMTTY -> Demodulator HAM Default at bottom center of panel to a Mark freq and 170Hz spacing then you will xmit and recv. with the tones at that frequency in the audio passband. This should put the tones well within the range of your filters on all bands It doesn't affect your "listeners" they can't tell where you set your tones as they see alternating "tones" 170Hz apart wherever they have their demodulator set. this is transparent, which SideBand you use isn't ...i.e. reversed or normal. Most folks use LSB on all bands though USB has some history in Europe - I haven't seen a reversed signal in a contest for a long time. See: http://www.rttyinfo.net/rtty_tutorial.htm >With help of GRAM I tried to move my filters to 2200 Hz center frequency. >- on 10 + 15m I could move the filters to 2200 Hz, on the lower bands it >would not work (the range was too small) >- then on the lower bands (20, 40, 80) I had to switch to "RTTY Rev" in >oder to move my filters to 2200 Hz. > >Is this the way RTTY works on a K2 ? > >Due to the fact I had to run "RTTY Rev" I also had to reverse the mode on >MMTTY. You also then force your listeners to do the same not conducive to effective operation >What filter bandwidth would you recommend ? Same steps as for CW ? Over the >weekend my smallest filter was 1.6 kHz and sometimes I had inband QRM (as >expected). I use a wide filter for general listening and looking for signals and "focus" in with narrow filter like 250-350Hz especially with crowded band during contest. There are some good resources on the web: http://www.rttyinfo.net/ http://www.aa5au.com/rtty.html And and active mailing list: http://lists.contesting.com/mailman/listinfo/rtty >73 de Dominik, HB9CZF BTW Thanks for the contact during the 'test at 17:36 on 15M ;<) GL & 73 Steve Holton N1NB ++++++++++++++++++ Date: Thu, 30 Jan 2003 10:22:09 -0800 (PST) Subject: Re: [Elecraft] RTTY Operations From: "Martin AC6RM" To: Cc: Reply-To: elecraft at ac6rm.net Hi Daniel; Check out http://www.winlink.org/ There is a network of PACTOR nodes set up that do internet email transfers. It's cool stuff. 73, Martin > > How do you get email access from anywhere?? > > Daniel > kg4dni ++++++++++++++++++++ From: "John-Morrow" To: "Elecraft List" Subject: Re: [Elecraft] RTTY Operations Date: Fri, 31 Jan 2003 12:11:26 -0000 As the K2 isn't capable of FSK, I didn't think > that anyone would be using an outboard TU with it, but I didn't realise > Julian, G4ILO. (RSGB, ARRL, G-QRP, K2 3#92) The main reason for using the tones 2215/2295Hz as afsk was that hopefully the harmonics generated in the audio stages of the tx would fall outside the ssb filter bandwidth. The profliferation of cheap/free soundcard software has been great at popularising rtty but some of the sigs on the bands leave a lot to be disired where some do not realise that afsk can generate more signals than they think! The most desirable way to generate rtty is by FSK. It should be possible to FSK the bfo of the K2. It would require a fimware change to give Rx/Tx tone shift similar to CW but with a tone greater than the 800Hz available at present. Perhaps the whole thing could be done in firmware. I use an external TU tuned to 1275/1445 only as tuning indicating to feed a scope with 'flipping bananas' but the decoding is done in software. This is the most accurate method for tuning rtty. Hence my requirement for a wide BFO range. 73 es gl John Morrow GI4KSH ++++++++++++++++++++++