[sdiy] Tempco 2k +3350ppm Group buy

[Grant Richter]

>
>
> The ideal temp coeff is 1/T.  It is not and should not be linear.  :-)

I was under the impression from previous discussions that the tempco  
changed with temperature and 3300 or 3500 etc. was just an  
approximation for room temperature.

I have noticed this in actual VCOs that the slope changes slightly  
with temperature.

If for example you calibrate at 70 deg. F then at 60 deg. F or 80  
deg. F you will have a very slight slope error.

I am talking about changes in the extreme end of the range of +/- 2  
cents from original calibration, always in the same direction with  
temperature.

I guess it could be the summing resistors, but I use the 50 ppm metal  
ones. I always thought it was from the tempco math.