[time-nuts] Choke Rings and Points North

[Dave M]

With all the discussion about surveys & position accuracy, I have a question 
about my choke ring antenna.  There is an arrow marked "N" on the underside 
of the rings.  How accurately does the alignment need to be to "N"orth? 
True north or magnetic north (my thinking says True North)?

Does the directional accuracy affect the precision survey?  I'm assuming 
that it would have no effect on the accuracy of the 10 MHz frequency output. 
Or am I completely off base?

Dave M