KT81 intermediate

[Martin Czech]

Hi Rene and Ian and all, some intermediate result:

The list of KT81 typical values had a typo, sorry if this caused
confusion, this showed up when I computed a second order interpolation
formula for gnuplot:

-----------------------------------------------------------

kt81(c)=815+8.81*c
kt81_2(c)=0.0186*c**2+6.95*c+815

plot "kt81.dat"
replot kt81(x)
replot kt81_2(x)
#plot [0:100] (kt81(x)-kt81_2(x))/ kt81_2(x)

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kt81_2 is a good aproximation to a typical one (datasheet),
temperature in C (that's why the unusual c variable).

"kt81.dat" is now:

  0 815
 10 886
 20 961
 25 1000
 30 1040
 40 1122
 50 1209
 60 1299
 70 1392
 80 1490
 90 1591
100 1696


The relative deviation to the linear approximation kt81 is about -4% (maximum
at about 50C).


m.c.