Hi Dave and Ingo

> my a110's have these patch points on a separate front panel.
> if i recall right you just have to solder a jack
> to these points and you're done. but to be sure you should
> verify this and ask the technical staff at doepfer.

Have a look at
http://www.doepfer.de/a110_tec.htm
though there is no description in the text, you can see the features and
how to connect them in the schematic.

> soundwise i'd say that linear fm on an a111 sounds better,
> but anyway it is always nice to have linear fm capability
> available on a vco.

The main advantage of the linear-FM on the A110 is the possibility to
bypass the input capacitor - i.o.w.: DC-coupled FM. This is very(!)
useful with the theremin controller, but also with other continuous sources.

Florian