I've decided to take the plunge into digital modes and 'found' the RTTY mode (and extra set of filters) in the SEC menu. There is still much about my 1 year old K2 that I'm still finding out. What a radio!
When I went in to set the filters in RTTY mode and decided to check the SSB filters as well. Using Spectogram, I cannot ajust anything to make the 300 cycle point at -60 db down. I CAN adjust it such that it is -60 db down at 2500 hz. There appears to be no low frequency roll-off at all. Adusting the BFO moves the high frequency point; it does not move the low frequency point. My setup: K2# 6110. AF option is OFF and switched out of the circuit. I'm using the External Speaker Output to drive the sound card. I don't see this porblem with the CW filters. Is this normal? Received SSB signals sound fine. 73, Clark KE4RQ Don Wilhelm-3 wrote: > > JT, > > There is nothing wrong with AFSK - in fact, if the carrier balance on > the KSB2 board is adjusted correctly, AFSK is indistinguishable from FSK. > > The only 'problem' with the K2 is that the BFO range is limited, with > the result that narrow filters cannot be set with a center frequency > equal to the 'true RTTY' tones. MTTY and other soundcard RTTY programs > offer a selection of tone frequencies - so if you align your narrow RTTY > filters to at 800 or 1000 Hz, MTTY can accommodate that center > frequency. When I set up RTTY filters on a K2, I set the FL1 filter the > same as the SSB filter and then set FL2 at 1.00 kHz, FL3 at 0.70 and FL4 > at 0.400. The narrow filters are centered at either 1000 Hz (or 800 Hz > if the BFO range will not accommodate 1000 Hz for the 0.40 filter on > both sidebands). In operation, the RTTY signal is tuned to center on > 1000 Hz (or 800 Hz) and the program will decode the signal - > transmission will occur at the same offset and noone on the receiving > end will know whether you are using real FSK or AFSK. > > So the short answer is: the K2 will operate just fine on RTTY, and yes, > you can use narrow RTTY filters to minimize the QRM. > > 73, > Don W3FPR > > John Tobias Croteau wrote: >> How well does the K2 work in RTTY mode? I presume it is AFSK only? I >> seem to recall that some do not recommend the K2 for serious RTTY >> operating but I don't remember the reasoning behind this. I vaguely >> recall reading this about 2 years ago from somewhere. >> >> I'm a RTTY operator first then SSB. I've never been good with CW and >> probably never will so I focus on these two modes. I know it's a poor >> attitude but let's just not go there, at least I am honest about it. >> Most of my RTTY operation is centered around contest weekends simply >> because I can only operate portable due to antenna limitations at the >> home QTH. However, I am not a hardcore contester. I merely operate >> during the contests to maximize QSO numbers although getting a good >> score never hurts. >> >> Around August, I'm finally going to be able to upgrade to something in >> the K2 price range. Will the K2 be acceptable for the way I operate >> RTTY or should I hold out for a K3? I know the K3 will be a much >> better data rig. I can't really afford a K3 but I could probably make >> it happen. >> > _______________________________________________ > Elecraft mailing list > Post to: Elecraft@mailman.qth.net > You must be a subscriber to post to the list. > Subscriber Info (Addr. Change, sub, unsub etc.): > http://mailman.qth.net/mailman/listinfo/elecraft > > Help: http://mailman.qth.net/subscribers.htm > Elecraft web page: http://www.elecraft.com > > > -- View this message in context: http://n2.nabble.com/K2-RTTY-tp449714p840356.html Sent from the Elecraft mailing list archive at Nabble.com. _______________________________________________ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
