Archive of the former Yahoo!Groups mailing list: Yamaha CS80

previous by date index next by date
previous in topic topic list next in topic

Subject: Re: [yamahacs80] SOLVED Re: Help! Note mess!

From: Andrew Kirkby <kirkbyte@...>
Date: 2011-04-05

Max,


Well i guess then there is no need for new sockets. Excessively
soldering/desoldering will definitely cause problems with traces. You
can use 0.1 ceramics which is what most manufacturers would use for
decoupling. Trace side is probably easier, just make sure you solder
them to the correct pins :)

I always use TI CMOS which is the CD40xx series. No problems there.

You can replace Tantalum caps with Panasonic FM series caps which i
believe are designed as Tantalum replacements. I will investigate this
further for you as to the best possible result.

Adding high precision trimmers will solve a lot of problems with
stability. I am trying to find a good voice board trimmer replacement
but it is difficult to find a high precision trimmer with the leads
and adjustment screw in the correct orientation. If anyone knows of
one, let me know :) I have a CS80 and CS60 to update.

AK


On 06/04/2011, at 3:26 AM, Fernando Zarone wrote:

> Hi All,
> due to the fact that most of the IC sockets had been already
> soldered in place (correctly, by our friend Tommy from Bologna,
> previous owner...), is it convenient to avoid replacing them again
> w/ Mill-Max, both for economic reasons and for not burning the
> traces, soldering, instead, on the trace side ceramic 0.1 caps?
>
> As to the ICs, are the CD series ones OK (CD4016, CD4069 etc.)?
>
> Last: can the two tantalium blue caps in the KAS (1uF and 22uF) be
> replaced with two simple electrolytic, more reliable ones?
>
> BTW, I replaced all of the trimpots both in the KAS and SH with 8x2=
> 16 perfectly fitting 10K multiturn ones. The same done with the BA
> VR3 100K one (calibrating the 4.00 ref Voltage) = great!
>
> Il giorno 05/apr/2011, alle ore 14.33, Andrew Kirkby ha scritto:
>
> > Hi Max,
> >
> > Personally i'd just add decoupling caps and replace ALL the CMOS in
> > the unit with new TI stuff. All the old CMOS in the unit will fail -
> > i'm actually surprised it has lasted this long. CMOS is pretty cheap
> > though if you are using good quality Mil-Max machined sockets the
> cost
> > increases by a rather a large amount :) Also, if you replace all of
> > the parts in the PSU with new ones you can basically avoid the root
> > cause of all these issues. I'd also check all of the voltages with a
> > very high precision multimeter if possible, just to get it spot on.
> >
> > In any case, you will get a CS80 that will be inherently more
> reliable
> > or at least a lot closer to how it was out of the factory.
> >
> >
> > Andrew
> >
> > On 05/04/2011, at 4:56 PM, max fazio wrote:
> >
> >> Hi Andy
> >> I've read somewhere about a custom project which enabled to isolate
> >> the most critical points (KAS, SH, TKC) from occasional shocks and
> >> PSU failures; anyway it looks pretty foggy to me, as I've read
> about
> >> it many years ago and lose the documentation! Did you have some
> more
> >> infos?
> >> Thx
> >> M
> >> --- In yamahacs80@yahoogroups.com, kirkbyte@... wrote:
> >>>
> >>> Hi Max,
> >>>
> >>> That is good news. Just as i had suspected...
> >>>
> >>> Where do you want to put more fuses?
> >>>
> >>> Andrew
> >>>
> >>>
> >>>
> >>>> max fazio <faxiomas@...> wrote:
> >>>>
> >>>> Hi all
> >>>> Happily we solved the problem: 2 4016 CMOS brought their soul
> >> back to
> >>>> the Almighty but , at least, no other problem was found; can
> >> anybody
> >>>> tell me about how to modify the tracks in order to be able to
> >> put more
> >>>> fuses?
> >>>> Thx
> >>>> --- In yamahacs80@yahoogroups.com, "Max Fazio" <faxiomas@> wrote:
> >>>>>
> >>>>> Hi
> >>>>>
> >>>>> Sounds like some CMOS shorted out. Which fuse blew?
> >>>>>
> >>>>> Apparently the one on the left if you look from a higher pov
> >> with the
> >>>> keyboard in front of you
> >>>>> Update: now tensions are regular, those with scary settings
> >> are the
> >>>> ones between KAS and SH
> >>>>> M
> >>>>>
> >>>>>
> >>>>> ----- Original Message -----
> >>>>> From: Andrew Kirkby
> >>>>> To: yamahacs80@yahoogroups.com
> >>>>> Sent: Sunday, April 03, 2011 4:32 PM
> >>>>> Subject: Re: [yamahacs80] Help! Note mess!
> >>>>>
> >>>>>
> >>>>>
> >>>>> Sounds like some CMOS shorted out. Which fuse blew?
> >>>>>
> >>>>> Sent from my iPhone
> >>>>>
> >>>>> On 04/04/2011, at 12:27 AM, "max fazio" <faxiomas@> wrote:
> >>>>>
> >>>>>> Hi all
> >>>>>> I'm writing on behalf of Fernando who's got another problem
> >> with
> >>>> his machine which was eventually about to be fully restored.
> >>>>>> While removing one board in the voices' rig, one of the fuses
> >>>> suddendly blew up and the main voltage jumped to +20V. After he
> >> restored
> >>>> the correct voltage he experienced all kinds of weird sounds
> >> coming off
> >>>> the CS-80.
> >>>>>> I only hope that the KAS didn't break up, so please can you
> >> give
> >>>> me any advice or diagnosis about this problem.
> >>>>>> please help
> >>>>>> M
> >>>>>>
> >>>>>>
> >>>>>
> >>>>> [Non-text portions of this message have been removed]
> >>>>>
> >>>>>
> >>>>>
> >>>>>
> >>>>>
> >>>>> [Non-text portions of this message have been removed]
> >>>>>
> >>>
> >>
> >>
> >>
> >
> > Andrew Kirkby
> > (e) kirkbyte@...
> > (m) 0416 000 070
> >
> >
> >
> >
> >
> >
> > [Non-text portions of this message have been removed]
> >
> >
> >
> > ------------------------------------
> >
> > Yahoo! Groups Links
> >
> >
> >
>
>
>

Andrew Kirkby
(e) kirkbyte@...
(m) 0416 000 070






[Non-text portions of this message have been removed]