[RTTY] 200 hz filter on RTTY

[Don Hill AA5AU]

Test driving a new Icom IC-7600 on consignment from Icom.

Tonight there were several us in New Orleans trying to copy E4X on 10140 kHz.  There was a very strong steady signal right on his
mark frequency.  After a while, the carrier moved down about 40 hz.  At that time, I implemented the 200 hz filter on the '7600 and
the carrier completely disappeared from the passband and I was able to copy about 80-90%.

Something else the '7600 that the PRO III does not and that is the notch filter works on RTTY with the Twin Peak Filter turned on.
Didn't help with the signal when it was right on his mark frequency though.  Not much you can do about that although I have heard
rumors of a modem that could actually copy Baudot hearing only one of the two tones, but this could have been a HAL myth.

I think I remember someone, maybe Chen, saying a 200 Hz filter would not work on RTTY or something to that effect.  Maybe I don't
have the story just right, but it appears to be working great.  Too tight for contesting, but works when required.

73, Don AA5AU
http://www.aa5au.com
http://www.rttycontesting.com