[sdiy] Magic little box

[Scott Bernardi]

First, use 4066 not 4016 for the switches, they have superior specs.
If you're going to run it off a +9v supply, you'll have to capacitively couple
your signals.  What you might want to do is use two 9v batteries connected to
give you +/- 9v, and then a 78L05 and 79L05 regulator to regulate to +/-5v.
Then all you need would be circuits to translate the 0v to +5v gate signal to
-5v to +5v.  You could use a quad comparator like the LM339 for this. It would
run between the +/-5v, giving the desired output. If you put a voltage divider
of two equal resistors from +5v o the - input of the comparator, then when the
input gate was below +2.5v the output would be at -5v (4066 off) and when it
went above +2.5v the output would go to +5v, turning the 4066 on.

Aku Raski wrote:

> Good people of SDYI,
>
> Hello all, my name is Aku and I've been subscribing this list for quite some
> time now. The techinical superiority in the list is usually too overwhelming
> for me but the good spirit that the list is enjoying makes it still pleasure
> to read.
>
> I was hoping If somebody of you would have ideas or pointers of how I could
> get the following idea to work:
>
> I'd be interested in building multiple very simple cmos spst switches that
> I'd be able to controll with my midi to cv-gate interface by sending gate
> signals to the IC. The idea was to have a some kind of a cmos switch circuit
> (4016?) that I would place in a small enclosure and mount jacks outside the
> box. Preferably so that it would be powered with a single 9V battery.
>
> What I'm hoping this simplified "VCA" would do is to have a signalpath from
> A to B that would normally be unconnected, but as soon as the trigger input
> in the IC would receive a positive gate  signal(+5) from the cv-interface it
> would connect the A and B.
>
> The material going thru the pathway is totally uncritical and low in voltage
> and not expected to fill any hi-fi standards.
>
> Best to you all,
>
> Aku

--
Scott Bernardi
sbernardi at home.net