[time-nuts] EFC divider resistors

[Perry Sandeen]

All,
 
The REF 102 from TI is a +10 reference with a TC
of 2.5PPM/max. Using two 1% 50 PPM metal film Xcion resistors on can make a +5 V regulator that is
far superior to a 7805.  Cost is about $7
from mouser.
 
If one needs to have an adjustable resistor in a
circuit perhaps one of the digital pots that are available will suffice.
 
A question: would thermal cycling oscillators or reference
boards be useful before starting a stability run?
 
Regards,
 
Perrier