[sdiy] 2164 Expo VCO tracking

[Ian Fritz]

At 10:38 AM 4/12/2010, blacet at blacet.com wrote:
>One technique is to place the board in a styrofoam cooler to avoid air
>current effects. You can also place a heater inside and/or place the
>cooler in a refrigerator (take off the lid for about an hour) or outside.

This can work, but be careful.  Cooling a circuit too far this way often 
results in moisture condensing.

Also be careful about convection currents in the cooler.

When doing temperature testing, I always put the PCB in a small closed 
container lightly packed with crumpled up newspaper to effectively 
eliminate drafts.  This is the only way I have been able to measure 
temperature drift under 100 ppm reproducably.

Ian