Posted by
VR2BrettGraham on
Dec 27, 2006; 3:10am
URL: http://elecraft.85.s1.nabble.com/K2-frequencyh-stability-tp442294p442295.html
KI6WX added:
>I believe the N1KO data was that he observed a drift of 80 Hz, not
>800 Hz. A drift that large would indicate something seriously wrong
>in one of the oscillators. The current K2 design is not as good as
>a TCXO, but it is a lot better than an unstabilized crystal
>oscillator. It should be possible to reduce the drift to
>significantly less than 100 Hz over a temperature range of 10-50C
>with adjustment of resistor RA in the temperature compensation circuit.
No, N1KO's post clearly said 800 cycles.
Some hours later that was then revised to 80.
By then I was out backpacking, I think. Since
then, I see that we have been told that another
manufacturer could not have sold a product to
amateurs in the quantity they appear to have with
both frequency accuracy & stability of less than +/-
0.5 ppm (-10 to 50C) due to use of single reference
for everything inside.
I also could not be using another product this very
moment that uses only crystals & is spec'd for
stability of +/- 5 ppm (-10 to 50C).
From cold, 20C ambient, 45 minute drift of ~12
cycles - though could very well be the beacon it
was tuned to drifts & my computer probably is not
really a good frequency counter to begin with.
Invalid points of reference, apparently (pun not
intended ;^).
Usual disclaimer - one's operations may or may
not suffer from some number of dozens of cycles
of drift due to temperature, likewise LSD (or
next-to-LSD) uncertainty may not be a problem if
you do not need to be absolutely certain you are
inside the band.
Now time for another hike.
73, VR2BrettGraham
_______________________________________________
Elecraft mailing list
Post to:
[hidden email]
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
http://mailman.qth.net/mailman/listinfo/elecraft
Help:
http://mailman.qth.net/subscribers.htmElecraft web page:
http://www.elecraft.com