[digitalradio] APRS Beginner Guide
-- Forwarded message -- From: Steve [EMAIL PROTECTED] Date: Mon, Sep 22, 2008 at 12:17 AM Yahoo Group : TMD700A Folder : Beginner Guide File : APRS Beginner Guide - K9DCI Ver 4.pdf Description : Ver 4 Basics to get started with simple explanations and menu settings. I posted this way to make searching in the archives easier. You can access this file at the URL: http://groups.yahoo.com/group/TMD700A/files/Beginner%20Guides/APRS%20Beginner%20Guide%20-%20K9DCI%20Ver%204.pdf -- 73, Steve, K9DCI
[digitalradio] New Solar Cycle Sunspot Group
Posted Tuesday September 22, 2008 at http://www.kn4lf.com/kn4lf5.htm : Today is the first day of the fall season. It began at 1545 UTC. A new solar cycle 24 sunspot group (S731) formed at N20W12 on Sunday September 21, 2008. It should be numbered as 11001 today by NOAA/SWPC. Officially the last solar cycle 24 sunspot group to form (#10993) was on May 4, 2008. Unofficially the last solar cycle 24 sunspot group to form was on August 2, 2008. For what ever reason NOAA/SWPC failed to number this sunspot group. 73 God Bless, Thomas F. Giella Lakeland, FL, USA [EMAIL PROTECTED],net
[digitalradio] RTTY newcomer looking for some information
I've been a ham for almost 50 years, but I never operated RTTY until about two weeks ago. It was an award offered by the Chinese for working their special event stations for the Beijing Olympics that was the catalyst. I'm using a KAM connected to an FT-1000MP Mk.V and the WinWarbler program from the DX Lab Suite. I'm using 500Hz filters, and using the shift and width controls to narrow the passband from there. My 250Hz filters seem to be too narrow and I'm not sure why that is. The biggest problem I'm having is tuning in weak signals and copying through QRM. I have a couple of books on RTTY dating back to the 1960's. They talk about using TU's that can decode with only the mark or only the space signal. This seems pretty straightforward, since the mark and space together provide 100% redundancy. I haven't figured out how to do that with what I'm running, and on weaker signals I'm finding a tuning error of only 10Hz can make the difference between copy and no copy. What do I need to do better? Are there any good recent books on RTTY? I have the ARRL HF Digital Handbook, but it only covers the basics. Thanks! 73, John, K9MM
RE: [digitalradio] RTTY newcomer looking for some information
Do you have AFC enabled? The MMTTY engine used in WinWarbler provides considerable flexibility in configuring its RTTY decoder; these capabilities are described in the MMTTY online documentation. I've been using the EU1SA profile for years, but have recently begun experimenting with a new profile optimized for RTTY DXing. 73, Dave, AA6YQ -Original Message- From: digitalradio@yahoogroups.com [mailto:[EMAIL PROTECTED] Behalf Of John Becker Sent: Monday, September 22, 2008 12:21 PM To: [EMAIL PROTECTED]; digitalradio@yahoogroups.com Subject: [digitalradio] RTTY newcomer looking for some information I've been a ham for almost 50 years, but I never operated RTTY until about two weeks ago. It was an award offered by the Chinese for working their special event stations for the Beijing Olympics that was the catalyst. I'm using a KAM connected to an FT-1000MP Mk.V and the WinWarbler program from the DX Lab Suite. I'm using 500Hz filters, and using the shift and width controls to narrow the passband from there. My 250Hz filters seem to be too narrow and I'm not sure why that is. The biggest problem I'm having is tuning in weak signals and copying through QRM. I have a couple of books on RTTY dating back to the 1960's. They talk about using TU's that can decode with only the mark or only the space signal. This seems pretty straightforward, since the mark and space together provide 100% redundancy. I haven't figured out how to do that with what I'm running, and on weaker signals I'm finding a tuning error of only 10Hz can make the difference between copy and no copy. What do I need to do better? Are there any good recent books on RTTY? I have the ARRL HF Digital Handbook, but it only covers the basics. Thanks! 73, John, K9MM
[digitalradio] DCC (Digital Communication Conference) Announced on QRZ.com
DCC (Digital Communication Conference) Announced on QRZ.com http://forums.qrz.com/showthread.php?t=176621
[digitalradio] Re: RTTY newcomer looking for some information
--- In digitalradio@yahoogroups.com, John Becker [EMAIL PROTECTED] wrote: I have a couple of books on RTTY dating back to the 1960's. They talk about using TU's that can decode with only the mark or only the space signal. This seems pretty straightforward, since the mark and space together provide 100% redundancy. I haven't figured out how to do that with what I'm running, and on weaker signals I'm finding a tuning error of only 10Hz can make the difference between copy and no copy. Decoding with mark only or space only was something that seemed like a good idea at the time to get improvement over the true-FM limiter-discriminator design. It didn't turn out to be all that useful, because when signals are so bad that they fall below the threshold for FM then they are so bad that you don't copy much anyway. I honestly don't know much about the modern sound card DSP decoders, but I imagine they detect the mark and space separately and then combine the results. What do I need to do better? Are there any good recent books on RTTY? I don't expect to see any new books on RTTY, because it is a technology that is pretty much as good as it is going to get. Better performance these days comes from the newer sound card modes. RTTY is mostly used now for contests and DX, and the reason I think is that it has very fast turnaround, so you can make contacts as quickly as possible. You don't care that much about accuracy so long as what you see looks like what you want to see, hi. Also back when RTTY was the only keyboard mode we had most hams were running quite a bit more power than is the norm today. 500 watts was pretty standard for RTTY back then. For general rag chewing today most everybody has gone to PSK-31. There is some tweaking you can do with RTTY things like the MMTTY engine, which has several different filtering and detecting options. Maybe somebody will speak up about how to use them to best advantage. You might benefit by putting on the whole MMTTY program and using it to learn how to take best advantage of the displays and features. As a 50+ year user of RTTY I hate to sound so negative about it; but the fact is that technology has moved on. Jim W6JVE
