[Elecraft] 10 MHz external reference - GPSDO

[Oliver Dröse]

Why would I need the TCXO-3 instead of the TCXO-1 when using the K3EXREF 
if the accuracy and stability is provided by the EXREF? Am I overlooking 
something here?

Tnx & 73, Olli - DH8BQA

Contest, DX & radio projects: http://www.dh8bqa.de


Am 11.03.2016 um 22:30 schrieb Edward R Cole:
> First one needs to realize that the TCXO establishes the basic 
> stability, so choosing the TCXO-3 over the TCXO-1 will provide better 
> stability and accuracy (these are two different things).  I bought the 
> TCXO-3 with my initial K3/10 purchase so the rest of what I say is 
> with the better TCXO-3 installed (if frequency is important then that 
> is first thing I recommend updating).
>
> Mostly, I use 28-MHz as a testing frequency since it is my VHF 
> transverter IF.  On 28-MHz with only the TCXO-3, I see 14-Hz 
> inaccuracy.  This 14/28000000 = 0.5 ppm (I think this is better than 
> Elecraft specs the TCXO-3).  Adding the EXREF I see 2-Hz which is 
> "about" 0.1ppm.  Measurements on 50-MHz are proportional.  I see 3-4 
> Hz accuracy using the EXREF.