[sdiy] Suitcase synth updates

[Electronium]

For what it's worth, if I remember my Electronotes correctly... BH indicates
a 100k pot & 33k resistor in series for variable CV inputs.  'course
anything significantly higher than your output impedance should work OK.

 MB
mike at electronium.com



Patchell wrote:

> Generally, if you want to add level control to one of the CV inputs, I use
a 100K linear
> pot.  Wiper goes to CV input of the VCO, one end of the pot to ground, and
the other end of
> the pot becomes the input.  With a 100K pot and the 100K input resistor,
you will not
> exactly get a linear response from the pot rotation...but, I have never
noticed it.
>
>
>
> charlie lamm wrote:
>
> > Wow!  The ASM-1 VCO looks great.  Thanks for the suggestion.
> >
> > I have a few questions that maybe someone in this group can answer.
> >
> > a) I assume to add level control to the various modulation inputs I
should
> > put a voltage divider (potentiometer--linear I would guess?) in series
> > with the 100K resistors.  To give me control of a modulation source, a
la
> > the front panel of an ARP Odyssey.
> >
> > b) Does anyone know of an already made PCB for a single ASM-1 VCO?
Core,
> > modified, or otherwise.  I see a 4-banger here:
> > http://hem.bredband.net/bersyn/VCO/VCOPCB_l.pdf
> >
> > But only need a single.  And of course the ASM-1 VCO's are part of a
> > bigger synthesizer PCB.
> >
> > On Wed, 8 Jan 2003, patchell wrote:
> >
> > >     This is one case where it is truely a VCO (we are talking about
the 3819 aren't
> > > we?)...(what we commonly call VCO's are generally CCO's, ie current
controlled
> > > oscilators).  But to tell you the truth...this VCO (core) is not all
that much simpler
> > > that the "Asm1" type oscilator, if you were to strip off exponential
circuit.  The
> > > ASM1 oscilator consists of one opamp, one comparator, a FET, a couple
of caps, and a
> > > handfull of resistors (for just a sawtooth output).
> > >
> > > charlie lamm wrote:
> > >
> > > > I really like how simple the VCO is.
> > > >
> > > > Can anyone suggest a suitable temp-compensated 1v/octave convertor
to
> > > > "slap on" the front of this?  That would make it perfect for a
project I
> > > > am working on....
> > > >
> > > > On Tue, 7 Jan 2003, Electronium wrote:
> > > >
> > > > > Hello all,
> > > > >
> > > > > I've made quite a few updates to my suitcase synth project
webpage:
> > > > >
> > > > > http://home.attbi.com/~michaeltbrown1/e_sdiy.html
> > > > >
> > > > > Any ideas/thoughts/comments/suggestions/criticisms would be
greatly appreciated.
> > > > >
> > > > > Cheers!
> > > > >
> > > > > Mike Brown
> > > > > mike at electronium.com
> > > > >
> > > > >
> > >
> > > --
> > >  -Jim
> > > ------------------------------------------------
> > > * Visit:http://www.silcom.com/~patchell/
> > > *-----------------------------------------------
> > > *I'm sure glad Merry Christmas comes just once a year
> > > * -Yogi Yorgensen
> > > ------------------------------------------------
> > >
> > >
>
> --
>  -Jim
> ------------------------------------------------
> * Visit:http://www.silcom.com/~patchell/
> *-----------------------------------------------
> *I'm sure glad Merry Christmas comes just once a year
> * -Yogi Yorgensen
> ------------------------------------------------
>
>