How far away should I transmit from a rare DX station in RTTY? RTTY itself doesn't take that much bandwidth, but I've heard that I should be spaced 2-3 kHz away. Is that true? Thanks!
Generally the RTTY Bandwidth is 170 hz, So if the frequency on your transceiver reads 14082.00 Khz - the lower part of the RTTY signal is at 14082.00 Khz - 170 hz which is 14081.83.
That frequency allocation is being used, now if you have very good filters in your "rig" - then you could in theory operate very very close to this frequency - i.e. 14082.4 (that would be your Mark... the lower end would be 14082.230) which would leave a theorectical gap of aprox 400 Hz....
If the other station has No Frequency Variation and all the people calling them are also very careful - you will not have any issues.... assuming of course that your HF Transceiver has good Filters and Image Rejection.
Alas lots of stations just use pure power and literally burn away the edges....
What would I use ? On a non Contest day 500 hz is easily enough - but for CQWW-RTTY ... you will not have any space in the digital allocation - and the quest for power plus filters will become more significant.
If there is a DX station, and I note that you have said a rare DX station - then there is always the possibility that they will work a split, i.e. receive on 1 frequency and transmit on another (hence most/all(?) modern transceivers have 2 VFOs). The size (gap/distance) of the split is totally down to the DX operators choice, whilst this is very common in CW and SSB modes, it is less common in RTTY from what I have observed. In CW a split of +1-2Khz and SSB +3-5Khz. You however need to ensure that you are keeping your signal inside the allocated band, and (US Bands) adhere to the band plan if applicable.
If the DX station has been going for several minutes (and the DX Cluster will indicate that clearly) - and they do have a split - respect that. If they are working SIMPLEX (1 Frequency) then my 500hz offset is more than enough.
Some clever ops - deliberately position themselves close to DX stations - so those people who have been trying to get the DX and who can not (lack of Power/Ant/Propagation etc), and who are disappointed/frustrated so they try their luck for another station (just checking there is something coming out of the antenna).