Hello Dieter

> If I'm not mistaken 8 S&H's and switches are required for a 4 stage analog
> shift register (similar to the BBDs) as you need a n additional slave S&H
> for each stage.

I do not think, you need an additional slave S&H, if you decouple not
only the s&h with the input selector, but also the trigger, which clocks
the s&h.

> This is required to have the analogue value available to
> forward it to the following stage as the preceeding S&H already is
> "reloaded" from the stage before.

I would avoid to forward the content of one stage to the other (causes
voltage loss and adds noise). Instead of, I suggest to use a clocked
1to8 switch, to switch the output of one s&h-stage to the eight outputs.

Let me try ASCII sketch (you need courier as font for this):


|--common part--|--for each stage-------|

+-... +------out-bus-5
| |
+-... +------out-bus-6
| |
+-... +------out-bus-7
| |
+-... +------out-bus-8
CV in o---| |
+-----s&h_5--+------out-bus-1
| | |
+-... | +------out-bus-2
| | |
+-... | +------out-bus-3
| | |
+-... | +------out-bus-4
CD4051 | CD4051
|
+-... |
| |
+-... |
| |
+-... |
| |
+-... |
| |
Clock in--| |
+------+
|
+-...to s&h_6
|
+-...to s&h_7
|
+-...to s&h_8
CD4051

The assignment of the outputs at the right CD4051 has to change round
robbing.

Not shown is a adress counter, clocked by the clock, which feeds all
CD4051 (of course we should not use 4051 because of the know pitfalls).
The outbut buses should not require adders, becaus always only one



Florian