[Elecraft] To zero beat or not to zero beat

[N4ZR]

Ever since I have owned my K3, I have noticed that most spots put the 
K3's receiver above the actual frequency of the spotted station.  
Initially, I thought this might have to do with DX spots being rounded 
to the nearest 100 Hz, but then I realized that, if that were the case, 
X percent of spots should be high, X low, and Y (whatever percent) 
effectively right on.

I've checked the K3's calibration, and it appears to be right on at 10 
and 15 MHz, tuning in CW mode to WWV's carrier at my preset beat note.  
One possibility that occurred to me is that perhaps the DX cluster 
convention is always to round up, rather than up or down.

Seems a little unlikely to me, but does anyone know the answer?  I'm 
perfectly happy to keep jogging the main tuning knob a bit on most 
spots, but thought I'd ask.

-- 

73, Pete N4ZR
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