Vintage Synth Repair

Hi Wayne

 

It doesn’t list in the online list as CP-30, do you by chance have any other numbers?

 

Regards

Brian G3OYU

 

From: vintagesynthrepair@yahoogroups.com [mailto:vintagesynthrepair@yahoogroups.com] On Behalf Of Wayne
Sent: 25 February 2010 3:51 PM
To: vintagesynthrepair@yahoogroups.com
Subject: RE: [vintagesynthrepair] Re: Yamaha TG33 power supply

 

  


Brain,

 

     You stated that you have access to the full line of scans from Yamaha. I was wondering if you could help me with my Yamaha CP-30. It was offered for free in a local free-cycle group because it blew the fuse when it was powered on. Troubleshooting would be much easier if I had a skematic. So I ask if you have one or know if maybe the fuse should be slowblo? Any help would be welcome.

 

Thanks

Wayne

--- On Thu, 2/25/10, Brian <brian@...> wrote:


From: Brian <brian@...>
Subject: RE: [vintagesynthrepair] Re: Yamaha TG33 power supply
To: vintagesynthrepair@yahoogroups.com
Date: Thursday, February 25, 2010, 6:14 AM

  

Hi Royce

 

No problem.  I have access to the entire Yamaha on-line database, plus I carry a 3 CD set of schematics.  I am a professional engineer repairing, to component level, electronic keyboards and guitar amps.  Similarly I have access to the Kawai, Fender and Marshall databases.  Regrettably many of the other manufacturers don’t treat me as well!!

 

Your power supply schematic was lifted direct from Yamaha hence the excellent scan. 

  

Yes I would say that 12V should be OK, but as previously suggested I would check on the temperature of the various regulator components to ensure that things are not over-heating. 

  

As an example of this my local church has a Yamaha P80.  The power unit supplied gave a lot of trouble and I repaired it on several occasions.  Then the inevitable happened I setup the unit for the pianist one Sunday morning only find that the power unit had failed.  I rushed back to the workshop and picked up a selection of spare power supplies and plugged in a Kawai unit that gave out 20V, whereas the Yamaha unit only gave 12V.  Two years on and all is still fine! 

  

Regards

Brian G3OYU 

  

From: vintagesynthrepair@ yahoogroups. com [mailto:vintagesynt hrepair@yahoogro ups.com] On Behalf Of Royce
Sent: 25 February 2010 9:38 AM
To: vintagesynthrepair@ yahoogroups. com
Subject: [vintagesynthrepair ] Re: Yamaha TG33 power supply

  

  

Thanks Brian.
What a great scan. I wish I could get my ccts to scan that well.

Looks like there is a 5V reg for the digital and the full voltage is sent to power some OpAmps 
As well there is a split off regulated with a 9.1V 1A zenner but most of the load is passed through a transistor. I assume it is on a heat sink.

Did I miss anything?

So 12V should be OK.

Thanks again
Royce

--- In vintagesynthrepair@ yahoogroups. com <http://us.mc558.mail.yahoo.com/mc/compose?to=vintagesynthrepair%40yahoogroups.com> , "Brian" <brian@...> wrote:
>
> I can offer you a copy of the whole cct, however you should be OK with 12V
> but you may want to check the operating temperatures of the regulator ccts.
> 
> 
> 
> If the Yahoo system removes the attachment contact me off list.
> 
> 
> 
> Regards
> 
> Brian G3OYU
>