[sdiy] Op amp notes

[Paul Higgins]

> You know my experience that Analog Devices has always been supportive 
> of DIY
> efforts even before they had their "small order" desk.

Didn't even know about the "small order" thing; I've always bought 
parts through the big suppliers like Digi-Key and Allied.

> So from my experience i think it was harder to get SSM when they where 
> stand
> alone or when PMI owned them.  If you follow the literature from the
> beginning it looks like the real attrition of SSM synth leaning was 
> after
> the PMI buyout.  All the sudden the datasheets either understated or 
> deleted
> ref's to synth's.

That sounds about right according to what I can remember from the time. 
  I've got an old app note book from the PMI era and it's heavy on the 
pro audio apps.  Of course, this was about the time that everyone was 
being told they should dump their analog machines and go all digital.  
I'm sure that was a factor too.

> But like all analog, if it doesn't "place" into a cell phone or other
> commodity it's gone. So even the discretes you build with are a target
> (sadly).

Right.  I often wonder if we'll eventually be back to the situation of 
the late '70s-early '80s, before we had decent low-noise parts.

-PRH