I was asked to provide this - like I'm an expert ;) - but I did some digging and this seems to be a good start. If anyone else has further info please do chime in.
First, the information I have received is that the following frequencies within the RTTY segments may contain emergency traffic. Please take steps to avoid them:
7045, 7060, 7075, 7090
14120
These are all phone nets and we are asked to give them wide berth (phone bandwidth). For obvious reasons there may be weak stations you can't hear but others are trying to hear them. (Source: ARRL and others)
Also don't forget about the beacons at 14100 and 21150 - NCDXF recommends giving them 500Hz on either side, at least. (Be nice if 21150 was actually an issue!)
And of course, there are our friends using various other digital modes in the 70-80Khz segments on each band.
And remember that the US 80m RTTY band is limited to 3500-3600. Non-US stations CQ-ing above 3600 please consider listening below as well.
Have fun! 73 jeff wk6i
ps: Please do not avoid 10m. Take a listen and throw out a couple CQs. You never know.
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