> While locked to the external source, the K3’s reference
> oscillator frequency is maintained within 2 Hz.
The K3's reference oscillator is 49.380 MHz (+/-) not 10 MHz.
The K3EXTREF uses the external 10 MHz signal to gate a counter
which counts the reference. That count is then used to adjust
the reference frequency. Maintaining the 49.380 MHz reference
+/- 2Hz is on the order
of 0.04 ppm.
73,
... Joe, W4TV
On 3/11/2016 1:07 PM, David Anderson wrote:
Dick,
I found the reference to that figure I quoted, it is in the K3EXREF
manual:
The K3EXREF option locks the K3's reference oscillator frequency to
an external 10 MHz source by automatically controlling the REF CAL
function. While locked to the external source, the K3’s reference
oscillator frequency is maintained within 2 Hz. Since the K3EXREF
does not phase lock the K3’s reference oscillator, the external 10
MHz source has no impact on the K3’s phase noise performance. For
best performance we recommend your K3 be equipped with the KTCXO3-1
high stability (0.5 ppm typ.) reference oscillator.
73 from David GM4JJJ
On 11 Mar 2016, at 16:55, Richard W. Solomon <[email protected]>
wrote:
I am a tad confused over this issue. Perhaps I need to read up on
how Elecraft controls frequency.
My understanding on a "Locked" frequency would infer that the
result would be a LOT closer than 2 Hz @ 10 MHz.
Is there a detailed description of the process somewhere that I
could read ?
73, Dick, W1KSZ
______________________________________________________________
Elecraft mailing list Home:
http://mailman.qth.net/mailman/listinfo/elecraft Help:
http://mailman.qth.net/mmfaq.htm Post:
mailto:[email protected]
This list hosted by: http://www.qsl.net Please help support this
email list: http://www.qsl.net/donate.html Message delivered to
[email protected]
______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[email protected]
This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [email protected]
