• The move to the new server is done. There are some software and database maintenance updates in process. This has us passing the hat around to help out. We appreciate any donations. Seriously, even a dollar helps. The payment page may be found here - https://www.audiokarma.org/support.html

Cad new Yamaha CR-2020 capacitor board

Sorry for not getting back got kind of crazy. Put it all back together but while I didn’t let any of the smoke out, I also was not able to have the speaker safety relay engage. Since I replace 2 boards and did some work on the main amp boards as well I at a loss where to start. I have been generically been told to start at the amp an g backward but since i did no more than replay come caps and a resistor I have doubts that the issue is there. I am not comfortable providing my parts list at this time given that there is evidently an issue with my work and I have not narrowed down what it is.
 
FrankA said:
Sorry for not getting back got kind of crazy. Put it all back together but while I didn’t let any of the smoke out, I also was not able to have the speaker safety relay engage. Since I replace 2 boards and did some work on the main amp boards as well I at a loss where to start. I have been generically been told to start at the amp an g backward but since i did no more than replay come caps and a resistor I have doubts that the issue is there. I am not comfortable providing my parts list at this time given that there is evidently an issue with my work and I have not narrowed down what it is.
Click to expand...

Did you set the bias on the amplifier?
 
I put it back together and did the check and set the initial idle current voltage. It was way off as expected but it came into spec and seems to be holding. Unfortunately the safety circuit not engaging.
 
FrankA said:
I put it back together and did the check and set the initial idle current voltage. It was way off as expected but it came into spec and seems to be holding. Unfortunately the safety circuit not engaging.
Click to expand...

Boo…. That’s all I got. I’m too dumb to recommend anything else lol. Someone will chime in. Avionic.
 
Here's my work-in-progress @jayfree relay board BOM:

Diodes
D701-712,718: 1N4148
D713 ?
D714: 1N4002G
D715: TZX6V8D
D716-717: NZX14A
D719: 1N4004G

Capacitors
C701
C702
C703
C704
C705
C706
C707
C708
C709
C710
C711
C712
C713
C714
C715
C716
C717
C718
C720
C721
C722
C728
C729
C730
C732
C733
C735
C736
C737
C738
C740

Resistors
R702
R704
R706
R707
R708
R709
R710
R711
R712
R714
R721
R722
R724
R727
R732
R733
R734
R735
R737
R738
R740
R744
R745
R746
R747
R748
R749
R750
R762


Transistors
TR701: KSC2383
TR702: KSA1013
TR703: KSC2383
TR704: KSA1015
TR705: KSC2383
TR706: KSC1845
TR707: KSC2383
TR708: KSA1013
TR709: KSC1845
TR710: KSC1845
TR711: KSA1015
TR712: TIP41C
TR713: KSC2383
TR714: KSA1015
TR715: TIP41C
TR716: KSC1845
TR717: KSC1845
 
Last edited:
Id like one of these new relay boards for my CR2020, Ive already replaced the capacitor board. Does anyone have the relay board available?
 
So, I finished my 2020 finally using jayfrees relay and cap board. It sounds beautiful. I made a spreadsheet of all of the replacement components I used. I got the boards from JLCPCB or something like that in China. They already had the files on hand. They were about 40 bucks for 5 of each. I can certainly part with one.
 
Nuklhed said:
So, I finished my 2020 finally using jayfrees relay and cap board. It sounds beautiful. I made a spreadsheet of all of the replacement components I used. I got the boards from JLCPCB or something like that in China. They already had the files on hand. They were about 40 bucks for 5 of each. I can certainly part with one.
Click to expand...
is that possible you share your part list?
 
I have basically zero computer skills. My lovely bride helped me make an excel spreadsheet with the components on it. Can someone walk us through how to post the spreadsheet on here?
 
Thank you...
some lessons learned (the hard way!)
1. You must insulate the bottom of the relay board where it screws into the brackets underneath! I tried electrical tape and the leads poked through it and shorted. I found that 1/8 inch thick black rubber faucet washers epoxied to the brackets work great. You may need a tad longer screws.
2. The new boards are from JLCPCB. They have the gerber files. They are "yamaha_relay_b" and "yamaha_capacit."
3. I have tried using them in a 1020, with no luck. Looking at the schematics there are slight differences in the wiring, especially the grounding. Still working on that.
The attached file is a spreadsheet of components used. I dont have the specifics on caps and resistors, just values.
Good luck!
 

Attachments

As far as I know Member jayfree did a lot of work on them. He put the files on this forum for other members to use.
 
Nuklhed said:
As far as I know Member jayfree did a lot of work on them. He put the files on this forum for other members to use.
Click to expand...
That is what I thought but it was not 100% clear.
Are these boards identical to the originals, such as parts locations and traces?
 
Nuklhed said:
Thank you...
some lessons learned (the hard way!)
1. You must insulate the bottom of the relay board where it screws into the brackets underneath! I tried electrical tape and the leads poked through it and shorted. I found that 1/8 inch thick black rubber faucet washers epoxied to the brackets work great. You may need a tad longer screws.
2. The new boards are from JLCPCB. They have the gerber files. They are "yamaha_relay_b" and "yamaha_capacit."
3. I have tried using them in a 1020, with no luck. Looking at the schematics there are slight differences in the wiring, especially the grounding. Still working on that.
The attached file is a spreadsheet of components used. I dont have the specifics on caps and resistors, just values.
Good luck!
Click to expand...
Thx for sharing.
 
The Ecap board is very similar to original. The relay board is quite different, but they are both extremely well marked and use screw terminals instead of solder or wraps, which makes card removal or install soooo much easier.
 
Nuklhed said:
The Ecap board is very similar to original. The relay board is quite different, but they are both extremely well marked and use screw terminals instead of solder or wraps, which makes card removal or install soooo much easier.
Click to expand...
How many hours do you estimate it took to design each board?

Creation of these replacement PCBs is not an easy task and your efforts are commendable and greatly appreciated. The World needs many more people like you!

Have you designed other boards for other Yamaha units?
 
Last edited:
No, no, no. I had nothing to do with the design or creation of these boards. All that credit goes to jayfree. I simply found his design on this forum, ordered the boards, and somehow got them working. I was so sick of trying to repair burnt boards in 1020 and 2020 units. This was a godsend from Mr jayfree.
 
You must log in or register to reply here.
Back
Top Bottom