[Elecraft] 10 MHz external reference - GPSDO

[Gary Smith]

Something I have wondered since running MMTTY and looking at the XY 
scope is, why do I see the XY ovals shifting clockwise as the station 
is transmitting. I find decoding is best when the ovals are as close 
to straight vertical & horizontal. If I let them rotate, I lose the 
cypher so I have to actively adjust VFO A to maintain their proper 
spacing.

I always figured that rotational motion was caused by the time being 
shifted as temperatures increase in the TCO ovens and they do resolve 
as the radio cools down, only to experience heat and try and resume 
with the next transmission.

I see this same effect when in transmit albeit not as bad as some do 
on the other end. So my thoughts turn to what mitigates this effect 
on my end and I guess it has to be the TCXO crystals and their 
stability and its with the looser ones causing the greatest motion 
and lack of stability..

I have the higher rated TXCO-3 that supposedly gives basically stable 
transmit down to the occasional rated stability at I believe; to 
.5ppB, a many times better end at the final result.

So I wonder if in the real world, if my assumptions are correct and 
having a decent quality time medium to keep the GPDSO in persistent 
good order will keep the twisting of the TY scope bars more secure in 
place and better that the find the locations for best reading of the 
data?

And further because both rigs are experiencing different temperature 
shifts through the messages creation, it requires a greater stability 
of both top gave that high quality handshake. to stop this rotation 
of the XY coordinates from loosing connection?

I ordered one of the BG7TBL 2015-09-17 Disciplined GPDSO and find it 
uses different chips. These give a 5+ at 10x 000 000 000 800  The 
earlier on the Morion 201 gave a 1+-deviation at the same range. 
miniscule but somethig to consider. I'm hoping if my K3s is attached 
to this GPDSO and the ham at the other end is so configured so that 
neither unit will have grand shifting and a solid - uninterrupted 
signal will be the delightful norm.                                   
        	 	 t
So I'm hoping this strong desire to tame the K3s rock solid will 
result in perfect tight linearity.

I'm looking forward to seeing how well this goes.

73,
Gary
KA1J