[sdiy] tri VCO for Ring Mod?

[Michael Ruberto]

Thanks Harry, I'll check out Jim's site. I also found a place selling the 
2SA798 for .85/each.
The 2N3808 are a matched pair. VBE is 5mV max and hfe 20%. Not very 
impressive I guess. Although, I'm sure the guy will sell me the entire bag 
for $2.

M. A. Ruberto


>From: harrybissell <harrybissell at prodigy.net>
>To: Michael Ruberto <frankentron at hotmail.com>
>CC: patchell at cox.net, synth-diy at dropmix.xs4all.nl
>Subject: Re: [sdiy] tri VCO for Ring Mod?
>Date: Fri, 23 Dec 2005 23:34:39 -0500
>
>Actually... I think you can order them from Jim Patchell  :^P
>
>(so my swipe about him being a 'stockholder' actually has a grain of
>truth :^)
>
>iirc there are some details on his website. He bought a bunch so that he
>could get quantity pricing, and passes the savings along. I have done a
>few deals with him and trust him like my 
>"twin-brother-separated-at-birth"...
>
>H^) harry
>
>If the 2N3808 is a monolythic dual, Its probably quite usable. The MAT03 is
>really
>a top shelf device !
>
>Michael Ruberto wrote:
>
> > I never see anybody selling THAT products. Do you have to order them 
>from
> > China or something?
> > And has anybody else had the experience of having sales people from 
>American
> > Microsemi sending you 5 emails a day trying to get you to order from 
>them?
> > Rather agressive bunch.
> >
> > I'm liking the Bergfors design at the moment due to the lower parts 
>count. I
> > ws thinking about my local electronics parts place and how they have a 
>bag
> > of 2N3808 collecting dust in the back of their store room. I know they
> > aren't as tightly matched as a MAT03 but do you think they would be 
>worth it
> > for this application?
> >
> > M. A. Ruberto
> >
> > >From: harrybissell <harrybissell at prodigy.net>
> > >To: James Patchell <patchell at cox.net>
> > >CC: Michael Ruberto <frankentron at hotmail.com>, 
>synth-diy at dropmix.xs4all.nl
> > >Subject: Re: [sdiy] tri VCO for Ring Mod?
> > >Date: Fri, 23 Dec 2005 21:21:55 -0500
> > >
> > >Bold words from Jim Patchell (THAT stockholder)   :^P
> > >
> > >but seriously folks, the 2SA798 is a good, reasonably cheap
> > >PNP monolythic pair. Last time I bought (100's) they were in the $.35
> > >range. Probably more now... but should still be under a buck. I forget
> > >who I ordered from.  Maybe Old Crow remembers... but I don't even
> > >remember if he bought the NPN and I bought the PNP... anyway we traded
> > >some.
> > >
> > >American Microsemi was one source...
> > >
> > >H^) harry
> > >
> > >James Patchell wrote:
> > >
> > > > You can also use an OTA for doing the current steering..., the one 
>of
> > >Fritz
> > > > site is a good design...(not to say that Bergfors isn't...I just 
>haven't
> > > > seen it).  I have also used THAT140s (Now THAT340s) to do the same
> > > > thing.  They work pretty good.
> > > >
> > > > At 04:56 PM 12/23/2005 -0500, Michael Ruberto wrote:
> > > > >Hello,
> > > > >
> > > > >Since I came into possesion of a lot of AD632 multipliers I am 
>thinking
> > >of
> > > > >building a nice stand-alone Ring Mod effect box. I would like the 
>unit
> > >to
> > > > >include a carrier VCO with sine and tri waves. I have been 
>searching
> > >for
> > > > >triangle VCO designs and saw some nice ones from Fritz and 
>Bergfors.
> > >Has
> > > > >anybody else tried constructing these?
> > > > >
> > > > >Anyone know of a tri core VCO that doesn't require expensive 
>matched
> > >PNPs?
> > > > >Or how about some inexpensive matched PNPs?
> > > > >
> > > > >Also I would love some more ideas for features to add to my effect.
> > > > >
> > > > >Thanks!
> > > > >
> > > > >M. A. Ruberto
> > > > >
> > > > >PS: Merry Christmas!!!
> > > > >
> > > > >
> > > >
> > > >          -Jim
> > > > ***************************************************************
> > > > http://www.oldcrows.net/~patchell
> > > >
> > > > ***************************************************************
> > >
>