AW: CA3046 VCA

[Haible Juergen]

	>It is based on the circuit in Modulus. But I have modified it in a
couple of 
	>ways. The Modulus circuit has the following problems:

Interesting design - saw it for the first time.
Not the usual current mirror or differential amp after the variable
gm diff pair, but a loop to keep the current in one branch constant,
not unlike expo converters ... interesting !

	>2. A diode is added to the CV input. This does not mean that
nothing happens 
	>below 0,6 V CV, as you might suspect. The VCA starts to output
signal at 0,15 V 
	>CV. That is quite acceptable in my opinion.

Should work fine, like the one-pnp solution for ota vcas. A linear VCA with
an exponential part at the low end, or an exponential VCA with a limited
slope at the upper (dB) end, depending on the way you look at it.

Noise ?

JH.