[Boatanchors] Zero beat boatanchor on CW

[Artmouton]

I should really know the answer but I have probably been using a ricebox (FT-1) too long.  Finally got a working Valiant from an honest ham to go with my 75A-4.  Question, as set out in the subject, is what is actual "zero beat" for returning a CQ from another ham on CW?  If he is calling CQ do I zero beat on the receiver exactly or do I try and match the tone of my VFO (on tune) with his signal?  Also, with the A-4, one hears both sides of the signal, not just a selectable sideband as with the ricebox.  
Not that this is a question of great importance but I was having trouble being sure, on a crowded band, that my response to the CQ would be on that station's calling frequency so that he hears my call.
(also, it is really weird not to have break in, some fast CQ's (especially from DX stations) have a short wait period.  By the time I hit the transmit switch and get to the key to start sending, he is already calling again)
Art K5FNQ


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