Yamaha CS80

In the last five years, I’ve been working on the CS-80 Overall Circuit Diagram.

I cleaned the original scan, but also added colors to help localize the boards.

A lot of typos and oversights had to be fixed too (using either the service manual, or the CS-80 itself as a reference when needed). The layout of some parts was also modified to make understanding easier (this is particularly noticeable with the M board).

The file is provided as is.
If you still find errors, feel free to use this topic to list them. I'll update the file.

The file is a 14MB jpeg. Due to file uploading issues, I had to put it in a five parts split zip.

On Dec 22, 2014, at 10:07 PM, laurie@... [yamahacs80] wrote:

Hi ... thankyou for your effort

I downloaded the 5 files but my extracting programs says the file is corrupt and none of them will open.... could you re check 

Thanks again for your work....... 

>
> Downloading and unzipping the files works fine for me.
>

 

Speaking of replacing caps.  For years, I’ve replaced tantalums whenever working on old gear because of their problems like exploding.  There’s one-per-note on the TSB boards.  I just read in eetimes.com that there’s another important reason:

http://electronicdesign.com/blog/conflict-minerals-and-tantalum-capacitor-supply-chain

I had no idea they were connected with conflict minerals!

And I also didn’t realized what this did to the price when companies switched to non-conflict sources a few years ago:

http://www.infomine.com/investment/metal-prices/tantalite-ore/all/

 David

On Jan 8, 2017, at 9:17 AM, joachim.milson@... [yamahacs80] <yamahacs80@yahoogroups.com> wrote:

Hi Tom,

Thanks for pointing these issues.

You're right concerning the 100uF capacitors. There are 4 decoupling capacitors; two between ground and +15V, and two between ground and -15V. I changed the 33uF one near the IC1 to a 100uF, and I added a new 100uF one near the IC3 (which corresponds roughly to where it really lies on the board).

As for the 4.7uF capacitors, those on my boards are in compliance with the schematics. Two are polarized and are yet other decoupling capacitors (between -15V and +15V, this time). The other two are non polarized and are located near IC8 and IC9.

I updated the overall circuit diagram to reflect these. It is available here.

I also put in the photo gallery of the CS80 group a copy of the M-board schematic (p44 of the service manual) where I highlighted the 42 capacitors, and also fixed a couple of missing components and a label inversion (fixed in red). You can find it here.

Joachim