[time-nuts] NAA experiments as a reference

[David I. Emery]

On Sun, Sep 14, 2014 at 10:20:48AM -0400, paul swed wrote:

> I still do not see why if I offset the LO to -150 hz I get a useful display
> to judge timing. I am using the lissajous method.

	Consider that with the LO offset 150 Hz you will have a 100 Hz
beat note with the mark tone and a 200 hz beat note with the space
tone - more or less exactly right on if the MSK signal carrier is right
on (which it is) and the signal is true MSK (which is is) and the 150
Hz LO is nearly right on (which it presumably is).

	And the 200 Hz and 100 Hz are of course related and coherent
with each other (the phase of the mark and space tones is precisely
related to each other because of the nature of true MSK).

	This means the resultant waveform should be stable seen in
a sweep triggered by your local clock at 100 Hz and also in a lissajous
pattern with the LO.


-- 
  Dave Emery N1PRE/AE, die at dieconsulting.com  DIE Consulting, Weston, Mass 02493
"An empty zombie mind with a forlorn barely readable weatherbeaten
'For Rent' sign still vainly flapping outside on the weed encrusted pole - in 
celebration of what could have been, but wasn't and is not to be now either."