Re: Center Frequency when setting RTTY Filters
Posted by
Jeff Stai on
Oct 09, 2005; 7:55pm
URL: http://elecraft.85.s1.nabble.com/Center-Frequency-when-setting-RTTY-Filters-tp382766p382769.html
Ooops - I knew I would get dyslexic - it's LSB, so the necessary shift to a lower TX frequency requires a corresponding shift higher in the audio applied - so you want to center at 1000+(170/2) or 1085Hz.
sorry! - jeff wk6i
At 11:30 AM 10/9/2005, Jeff Stai wrote:
>You want to set it to the center of the two tones you are using for AFSK. If 1000Hz is your Mark frequency, and 170Hz is your shift, then you should center at 1000-(170/2) or 915Hz.
>
>You can do this graphically with Spectrogram using the techniques detailed on the Elecraft Builders Resources pages. Set the cursors based on the AFSK tones from your RTTY modulator software or hardware. Then center the filter peak between the two cursors.
>
>hope this helps! - jeff wk6i
>
>
>At 10:43 AM 10/9/2005, Charlie, W0YG wrote:
>>Since the ability to set filters when using the RTTY mode is different than LSB/USB if used for AFSK, what center frequency do you use? Perhaps I should rephrase this. When setting filters in the RTTY mode (the K2 defaults to the SSB filters when in RTTY mode unless RTTY filters are set) do you use 1000 Hz as the center frequency?
--
Jeff Stai
[hidden email]
Twisted Oak Winery
http://www.twistedoak.com/Rocketry Org. of CA
http://www.rocstock.org/Amateur Radio WK6I ~ Calaveras County, CA
_______________________________________________
Elecraft mailing list
Post to:
[hidden email]
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.htmElecraft web page:
http://www.elecraft.com