EI6IZ sed:
*****************
If you look at the sheet that came with your TCXO you might notice that
it does a good deal better than 0.5ppm without any calibration over the
temperature range that your radio goes through during operation. 
The TCXO in my k3 is better than 0.5ppm over the temp range -10C to
+50C. My Front panel temp as measured by the K3 is always around 37-40 C
and does not vary much 

you mileage may vary but the K3 with the TCXO already comfortably
exceeds 0.5ppm without the additional calibration. (which is coming.)
Therefore the K3 does not 'fail' to meet the 0.5ppm spec at present
*****************

EI6IZ apparently had good luck with his particular TCXO.  My TCXO data
sheet says, in part:

-10.00   -.39
  0.00   -.25
 10.00   -.03
 19.99    .05
 29.98    .29
 40.02    .60
 50.00    .73

As can be seen, my TCXO barely meets the 1 ppm spec from 0C to 50C,
as .73 - (-.25) = .98, but would fail that spec if measured from 
-10C to 50C.

So my particular TCXO does no better than its 1 ppm spec, and does
not achieve 0.5 ppm stability until it warms up to its operating
temperature, near body temperature (which is 37C).

While it is warming up, from room temperature at about 20C to operating
temperature at about 40C, my TCXO varies .60 - .05 = .55 ppm, more drift
than 0.5 ppm even during warmup in a typical house.

73, Paul W8TM


______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

Reply via email to