[sdiy] Cheapest Matched Pair

[Grant Richter]

Merry Christmas to All,

One other caution on the CA3046. If you use two sets of transistors
internally to make the expo converter for two VCOs. The VCOs will tend to
"soft synch" probably due to capacitive coupling in the CA3046.

Using Rossum compensation (diode and resistor) you can make an expo VCO that
tracks +/- 5 cents or better over 8 octaves.

> 
> Joe, Oren etal --
> 
> The CA3046 is indeed speced to 5 mV matching, but in practice it is usually
> much better due to improvements in Si technology in the years since the device
> originally came out.
> 
> Also the beta is usually much better than speced.
> 
> The main drawback of this array is the relatively high emitter series
> resistance.  This needs to be compensated for in critical converter
> applications.
> 
> If you can find it, the CA3083 is quite a bit better than the CA3046 in this
> regard.
> 
> Seasons greetings to all!
>