Wow, thanks for your help everybody. I guess that i am overly
confident with my soldering. It looks like I'm going to get a can of
deflux and follow everybody's suggestions. I do have a professional
desoldering iron. I kept it at 675 degrees farenheit and the iron at
650 when removing the old chips and installing the sockets. I'm going
to clean the boards and check with a magnifying glass. I'll be sure
to keep everybody posted. Thanks again.
One last question: What is the point of decoupling the -8.5 rail to
the +6.5 rail? Wouldn't it make more sense to go from ground to -8.5
and ground to +6.5? Everybody keeps telling me I should buy the
sockets with the cap in them, I don't understand how this makes sense
electrically.
Thanks again everybody.
--- In yamahacs80@yahoogroups.com, David Rogoff <david@...> wrote:
>
> Mike,
>
> I agree with Kent. As I told you, when I re-chiped my CS80 I had a few
> problems that were all tiny solder bridges between pads. I'd spend a
> bunch of time with a lighted magnifier to start. Do you know which
> board it is? I had strongly suggested to you that you only re-chip one
> board at a time to help isolate any possible re-work goofs.
>
> Good luck,
>
> David
>
> kent_spong wrote:
> > If I could make a suggestion to you here.
> >
> > Forget about the IC's being too fast or slightly different to the
> > originals. I think your barking up the wrong tree here.
> >
> > This sounds to me like a physical problem created by replacing the
> > IC's, and not the IC's themselves.
> >
> > When I KSR an 80 I use off the shelve new IC's, the make is of no
> > concern at all.
> >
> > If you have used dil sockets for the IC's, check for bent legs, pins
> > soldered together and even orientation. After doing over 60 CS80
> > restorations now I can still screw it up from time to time so don't
> > be offended if I sound like I'm putting your work down.
> >
> >
> > If you like, send me a detailed list of all the problems your having
> > and I will work through them with you to fix your beautiful synth (I
> > do love CS80's so much).
> >
> >
> >
> > --- In yamahacs80@yahoogroups.com, "mborish_2000" <mborish_2000@>
> > wrote:
> > >
> > > It might. Some of the older chips took forever to switch. I
> > haven't
> > > seen a datasheet for the original 4000 series Toshiba IC's. I'm
> > going
> > > to do that next. The new 4000 series chips have much lower
> > internal
> > > resistances.
> > >
> > > --- In yamahacs80@yahoogroups.com, "Quazimodo" <noddyspuncture@>
> > wrote:
> > > >
> > > > Mike I just Googled and read up on it (a bit..)
> > > >
> > > > Should you really worry... it looks like it would be in the
> > > > ∗nanosecond∗ region anyway.... or am I wrong..?
> > > >
> > > > Cheers,
> > > > TOM
> > > >
> > > >
> >
>