op-amps, Poly's

[LMVogue]

G'day all

First, what should be a simple question - how do you test whether an op-amp
is still operational, with only a multi-meter to go on?  I've got no idea.
All this talk of Poly800s reminded my to start trying to see if I can fix
my beast - someone suggested the op-amps could be a problem (lowdown - the
CPU was fried, this was replaced, the next chip in line was tested, nothing
coming out, replaced, still nothing.  I get no read-out on the LEDs, and
someone suggested that something else blown is probably blocking the system)

Speaking of the Poly800, here's a thought - they (synth makers) went from
analog interfaces to digital to make the thing programable, right?  Well,
why didn't(?) anyone come up with free-wheeling knobs with readouts under
them (eg. LEDs), with all knob-twirling leading to a programmable setting?
ie.  kinda like the virtual analogs now, but using real analog - shouldn't
have been very expensive, surely?  I can see why everyone's now going back
to analog interfaces - digital are a pain in the arse, and no fun to tweak!
; )
I wonder if all that made sense to anyone ; )

cya
LMVogue

PS hey, if you had a simple oscillator with it's envelope controlled by an
envelope follower running off a mic, would you get a very basic vocoder
thing?  Hook up a little keyboard to give you a bit of frequency control,
play a melody and sing into the mic... ????



_____________________________________________________ 
                 Lee Mulvogue
              LMVogue at earthling.net
            lmulvo10 at chec.scu.edu.au

 http://www.geocities.com/SunsetStrip/Palladium/3297