[Elecraft] K3 drift

[Ron Durie]

After 9 months of ageing my K3 # 604, I ran a cold to hot Reference
Oscillator Test.  

My Reference Oscillator is the Optional 1ppm Temp Compensated Crystal
Oscillator (KTCXO3-1).  
This TCXO came with a Factory calibration data sheet which shows
frequency verses temperature over a wide range.  

My Ambient Room Temperature was 72 deg F up to 74 deg F.  

At turn on (cold) the Reference was adjusted to WWV (15Mhz) and it
measured:  49,379,924 Mhz.  
After 5 min it measured:  49,379,925 Mhz.  
After 10 min it measured:  49,379,925 Mhz.
After 15 min it measured:  49,379,926 Mhz.
After 20 min it measured 49,379,928 Mhz.  That is an 4Hz shift up in
Reference frequency. 

For the next 14 hours it measured:  49,379,928 Mhz.  
It looks like it will stay there as long as the Ambient Room
Temperature remains near 74 deg F.  

This is Very impressive and will (can you believe it) get even better
when Elecraft enables the 1ppm TCXO Option in Firm Ware.
This will (for all practical purposes) eliminate the errors due to
temperature changes.   

The more I use my K3 and the more I learn about it the more I like it.
This is a very exciting and satisfying radio.  Thanks Elecraft. 

73's
Ron Durie
WB4OOA at arrl.net