[RTTY] CQ Worldwide DX Contest, RTTY

[David G3YYD]

I use a call history file which contains most of the active US RTTY contesters with state and zone being prefilled on the entry window (N1MM+). Have to be careful they have not moved but majority have not and I will update it with this year's contest.

I found that being off frequency has reduced considerably over the years and this year was the lowest so far. I had to use the QRZ F key while reaching for the RIT only a few times. Apart from the obvious radio RIT/XIT error then anyone using radio FSK has to be very careful to ensure they tune to the tone frequency set in the radio. Otherwise using AFSK makes it much simpler with TX netted to the AFC in S&P but NOT when running. If you are not heard when you think you should be check the TX is on the RX frequency.

I found that quite a number of Northern NA stations were better copy using 2Tone's Spread decoder. Maybe due to recent geomagnetic events, signal paths near the Auroral oval had their spectrum spread. 

(For the technically minded) The Spread decoder has tone filter bandwidth twice the bandwidth of the other decoders. Post detection low pass filtered to minimise noise/QRM from the wider filter which is needed to capture the signal energy with minimal amplitude modulation due to filter slope attenuation.

My SO2R station has never had a hardware failure in a RTTY contest, but this year was not my year. My 18 year old Alpha 99 (pair 4CX800) failed with a burnt off band switch contact - need a new wafer. The venerable Heath SB-220 (pair 3-500z) replacement transformer overheated and its protection cut out worked - I was making it work too hard! Even the rotator controller went down on me - not sure why. So Sunday mid-afternoon (local time), I decided to pack it in.

73 David G3YYD aka M7T (Thanks for the Qs)