Wiardgroup

I had a conversation with one of the design minds behind Apogee
Analog/Digital Convertors a few months ago that reflects much of the
same thought - Apogee has even considered buying on Ebay used AD8000
convertors in an effort to reclaim parts that are no longer in
production since the AD8000 was in production a few years ago, in an
effort to have parts in stock to repair units that are brought in for
repair.  'Oh, curse that unit that has lasted longer than a few years!"

He admitted that the state of the art was "disposible electronics: -
on the shelf this year, but gone forever in a few.

So it seems that Grant is right - there is no real guarantee that if
Wiard 300 goes SO that the SMD components needed will be available in
a few years.


gary



"Grant Richter" <grichter@...> wrote:
>
> What is truely shocking is that SO (small outline) SMD devices are
going EOL (end of life) in 
> as short as two years. SMD seem like it will have the same problem
as early eight bit 
> digital. The rate of change is very highly accelerated. 2708 EPROMs
are still available, but 
> you need an old programmer to recognize them.
> 
> It is beginning to look like the safest design strategy is to us a
mix of thru hole and SMD. 
> It appears DIP packs are sticking around longer than some SO chips
which are already 
> obsoleted.
> 
> Lead bearing technology is a know factor, while lead reduced
technology is still a big 
> question mark. And once again, car and motorcycles batteries and
stained glasses 
> windows in churches represent thousands of time more evironmental
lead contribution 
> that Wiard could possibly make in it's entire existance.
> 
> 
> --- In wiardgroup@yahoogroups.com, "Gary Chang" <gchang@> wrote:
> >
> > I would like to add to Doc's eloquent incites that many devices, such
> > as the Sequentix P3 sequencer, (which has been a rather large success
> > in the thru-hole era), could not be converted to the newer technology
> > in a way that was econimically realistic for its market place - and,
> > because of the EU's ban on such leaded devices being manufactured, has
> > now ended production.
> > 
> > At the very least, conversion of the 300 series to SMD would be very
> > costly - period.  Grant has already employed this technology on his
> > more recent devices (1200 series) - I suspect that he will continue to
> > do this in the future.
> > 
> > As for the "archival" 300 Series Modules that exist, I think that it
> > would be safe to assume that even at twice the price for components, a
> > 300 Series module is still more affordable to build today in its
> > existing design than turning it into a "TBD" module, pending the
> > costly and uncertain conversion to SMD, which would turn this cash cow
> > into a cash drain....
> > 
> > that''s just my opinion - I could be wrong.
> > 
> > 
> > gary
> > 
> > 
> > 
> > 
> > 
> > "drmabuce" <drmabuce@> wrote:
> > >
> > > Hi all
> > > 
> > > --- In wiardgroup@yahoogroups.com, "tom_tav" <tom_tav@> wrote:
> > > >
> > > > Unfortunately if you want to service an instrument somedays
you will
> > > sooner or later having 
> > > > problems to get something else then smd parts....
> > > > 
> > > 
> > > this is true, but the decision for a technological cottage
industry is
> > > anything but clear right now...
> > > 
> > > a few questions about surface-mount technology are stacking up in my
> > > mailbox so here's my take:
> > > 
> > > background:
> > > SMD,SMT,SOIC are all jargon for pretty-much the same thing:
> > > itty bitty parts that you can move with a sneeze and don't have any
> > > nice bendy wires stickin' out of 'em.
> > > the wiki on this subject is pretty good  
> > > http://en.wikipedia.org/wiki/Surface-mount_technology
> > > These things are made for the convenience of robots and not for
human
> > > fingers.
> > > 
> > > More germane to this forum is the issue of reparability. It's true
> > > that the older DIP devices will suffer from a scarcity of
replacement
> > > parts. But this evolutionary precipice in hardware is a bit
unique in
> > > that the components are virtually identical electrically but
they are
> > > physically much smaller.  In this way this is not like the migration
> > > from tubes to discrete transistors. The scale of physical
> > > miniaturization was comparable but  power environments moved
from high
> > > voltage unipolar to lower voltage bipolar and the active components
> > > had VERY different electrical properties. 
> > > SMD is optimized for mass production by automated processes.
Component
> > > level repairs are not part of the plan. The intention is to
reduce the
> > > cost of the circuitboard to the point that replacement is
cheaper than
> > > repair. This works pretty well for cell phones produced in
production
> > > runs of 50,000 units but those scales do not favor small run
esoteric
> > > devices. Small run SMD boards don't run cheap enough to garner the
> > > advantage of being disposable and replaceable.
> > > Component-level repairs to SMD are possible but significantly more
> > > difficult and time consuming .  i'd contend that the profile of
> > > increased risk and difficulty of SMD repair is different but
> > > equivalent to the tradeoffs inherent in through-hole (DIP) (ie.
easier
> > > repairs but scarcer parts). In a pinch I think it is easier to
adapt a
> > > smaller SMD chip to a through-hole application than the reverse.
> > > 
> > > The wiard designs (what's on the schematic) are very durable but
 the
> > > technology available to realize these 'songs in solder' is in a real
> > > state of flux right now.*** The consequences of the choices that
face
> > > Prof. Richter (and his colleagues) at this juncture are VERY
serious,
> > > and there is no path that offers a CLEAR advantage right now.
> > > 
> > > aleatoric music is way more fun than aleatoric livelihoods.
> > > 
> > > -doc
> > > 
> > > PS
> > > apologies to the group for all the button-thrashing empty posts this
> > > morning
> > > 
> > > ***
> > > even  -i- don't KNOW if that pun was intended or not
> > >
> >
>