> MMTTY used to send upside down in FSK and there was no way to > change it via software.
MMTTY does not "send upside down." It generates a "1" (high) on the output of the UART for mark which is correct. Most interfaces use a simple NPN transistor which turns that "1" into a closed contact (again correct for the old 60 mA "loop" circuits). Unfortunately, many rigs expect the FSK input to be OPEN (or high due to their internal pull-up) for Mark. The user needs to read his transceiver manual and if it is normally "mark open" or "mark High", select "REV" in the menu ... this applies to such a diverse group of transceivers as the FT-1000D, FT-1000MP, IC-706mkIIg, TS-870, etc. Again, MMTTY is not "upside down" ... it is the interface standards that are still rooted in the 60 mA current loop instead of the data communications world where Mark=1/Space=0. 73, ... Joe, W4TV > -----Original Message----- > From: [email protected] > [mailto:[email protected]] On Behalf Of Brian Alsop > Sent: Thursday, March 04, 2010 10:12 AM > To: Dave Hachadorian > Cc: Elecraft Reflector > Subject: Re: [Elecraft] RTTY via FSK-D > > > Comment on the FSK circuit. > MMTTY used to send upside down in FSK and there was no way to > change it > via software. > It is possible the circuit may have to be modified to invert > the polarity. > > 73 de Brian/K3KO > > Dave Hachadorian wrote: > > Comments interspersed. > > > > Dave Hachadorian, K6LL > > Yuma, AZ > > > > -------------------------------------------------- > > From: "Brett Howard" <[email protected]> > > Sent: Thursday, March 04, 2010 1:11 AM > > To: <[email protected]> > > Subject: [Elecraft] RTTY via FSK-D > > > >> So I'm thinking about wiring up the FSK IN pin on the AUX > >> connector to > >> do RTTY TX "properly". I'm curious of a few things before I > >> take the > >> time to make the cable. > >> > >> First off how do people usually drive this signal? I assume > >> its usually > >> taken off of a serial port... > > > > > > Yes, circuit is shown here: http://www.aa5au.com/rttyinterface.html > > > > > > > > > > I've tried a few RTTY apps and I've > >> gotten them all to work via AFSK and all seem to have their > >> pros/cons. > >> I have a feeling in the end that I'll probably most use MMTTY > >> being that > >> it has a very nice interface into N1MM (unless there is another > >> application that has a nice interface into N1MM that I should > >> be aware > >> of). > > > > > > MMTTY is the way to go. > > > > > >> Finally my last question is that if this comes off of a UART > >> how has the > >> timing been for people? > > > > > > The timing is solid. > > > > > > > > ______________________________________________________________ > > Elecraft mailing list > > Home: http://mailman.qth.net/mailman/listinfo/elecraft > > Help: http://mailman.qth.net/mmfaq.htm > > Post: mailto:[email protected] > > > > This list hosted by: http://www.qsl.net > > Please help support this email list: http://www.qsl.net/donate.html > > > > > > > ---------------------------------------------------------------------- > > -- > > > > > > No virus found in this incoming message. > > Checked by AVG - www.avg.com > > Version: 9.0.733 / Virus Database: 271.1.1/2721 - Release > Date: 03/03/10 19:34:00 > > > > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[email protected] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
