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-----Originalmeddelande-----
Från: rikard.latvala@...
Till: yamahacs80@yahoogroups.com
Datum: 2013-12-03 01:15
Ämne: Re: [yamahacs80] Re: Hello, new member with a few CS-60 questions...
Do you have access to an oscilloscope ? Try probing the output of the filter ic
Easiest way to do this is to solder a wire to the output pin or do as I did build
a small table that goes over the "board rack" that way you can have the boards out
and work on a flat surface while doing probing.
I might have an image of my little special solution I can put it in the file section
of the list.
Anyway if you have signal at the output of VCF check at the VCA if you have both in and out.
If i remember correctly VCA 1 is for sine and VCA2 for square&saw. Actually check all VCAs.
If you have input but no output make sure the 3:rd voice gets trig input while playing
the keys and that the Envelope actually works. If the Env doesn´t get trig check the
3:rd Transistor located on the KAS board right hand side in wards towards the "board rack".
the transistor for the 3:rd voice is the third one from your left If you have nothing here next
check the 4050 cmos ic. after this there is only the YM cpu & D/A ic´s from what i can remember.
-----Originalmeddelande-----
Från: leefordwatford@...
Till: yamahacs80@yahoogroups.com
Datum: 2013-12-03 00:45
Ämne: [yamahacs80] Re: Hello, new member with a few CS-60 questions...
Hi, finally got a little time to try swapping filter chips around, same issue.
I checked the trimmers, they seem okay, do I move on to wave shaper or oscillator? Is there a good way to work on these things? The socketed ICs were bad enough!
--- In yamahacs80@yahoogroups.com, Bob Stewart <bob@...> wrote:
>
> Might also be a filter chip failure causing the loss of square, saw and
> noise. Try swapping the filter chips with another card to see if the fault
> moves with the chip/s.
>
>
> On Monday, November 25, 2013, Rikard Latvala wrote:
>
> >
> >
> > Hey,
> >
> > about the light bulb, check if a well stocked gas station has them,
> > I think I've seen these 24v5w bulbs used in cars.
> >
> > If i remember correctly the squarewave output can be probed at TP4
> > on the M-card, and VR12 adjusts its output level. The trimpots used in the
> > CS 50/60/80 are in need of replacement, or atleast some adjustment
> > from time to time.
> >
> >
> > Skickat från min iPad
> >
> > 25 nov 2013 kl. 02:22 skrev "leefordwatford@...<javascript:_e({}, 'cvml', 'leefordwatford@...');>"
> > <leefordwatford@... <javascript:_e({}, 'cvml',
> > 'leefordwatford@...');>>:
> >
> >
> >
> > Hi, thanks for the group, lots of good info!
> >
> > I recently acquired a CS60, that mostly works pretty well.
> >
> > The first, and easiest issue is to find out a modern replacement for the
> > Touch Response light bulb. I'm having some trouble finding a 24v5w
> > equivalent. The #1864 seems close, but is 28v, and I'm not even sure it is
> > the correct base size.
> >
> > The only other issue I've found (other than the need for a good tuning
> > touch-up) is that the 3rd voice does not pass Square, Saw, or Noise. The
> > Sine wave works great, and all other cards work fully.
> >
> > Where can I start? I've read a few posts here about it possibly being the
> > Wave Shaper or maybe the VCF or VCF master level?
> >
> > Thanks!
> > lee.
> >
> >
> >
>