Yamaha CA-1000 desperately in need of assistance!

Oerets

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Picked up a CA-1000 knowing it was broken. Lucky for me I never powered the unit up. Was told it would not come out of protection.

Could see one one of the three speaker connectors were broken. On inspection just now I found a big mess and need someone who been inside one to help me figure it out. The wiring for the speakers is all wrong from what I see.

Wires cap off and looks wired up all wrong. Anyone have clue on what is what?

Just got upset and quit for now to tired to trace the wires back to the boards. Add to that the SM of mine is on PDF and a poor one. Plus already dropped it once today!

Barney
 

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the grey wires look like grounds ..beats me why bottom row are all grounds .
as for the other wires in the nuts i cant see what's going where .
 
Just looked again at it and the capped wires all are going to the transformer so they must be for different voltages. Yea I'm color blind with colors of shades and it appeared to me the three wires on the bottom were all the same color.
The only wire of a different color was a purple one connected to the red speaker terminal.

Barney
 
that design looks bad to me ..why they run transformer wires alongside speakers wires eludes me ..
anyway ..see where the bottom wire on the right goes too
or better still see where they all go too on the broke connector
 
Just looked again at it and the capped wires all are going to the transformer so they must be for different voltages. Yea I'm color blind with colors of shades and it appeared to me the three wires on the bottom were all the same color.
The only wire of a different color was a purple one connected to the red speaker terminal.

Barney

I may have one of those speaker spring clip strips if you need one. All six of the speaker connect wires should connect to the speaker select switch. The center commons are tied to ground.
 
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I may have one of those speaker spring clip strips if you need one. All six of the speaker connect wires should connect to the speaker select switch. The center commons are tied to ground.

That would be nice. They came out when I worked at a Audio store. They carried Yamaha and I always wanted one.

Want to get this going so bad!



Barney
 
Ohm'd the wires in question and I think it is correct. Just can't figure out why the three wires going to the bottom connector are all the same color. The center two are grounded to chassis as a common ground would be. The other on the right outside is open to ground.

Since the fuse was missing I replaced it with a 5A and on a dim bulb applied power. No click, fuse did not blow. So more testing to be done later.


I will ask the question here before starting a new thread if need be.

What if any are the differences in the CA-1000 and the CA-1000II? I have only a poor copy of the CA-1000II to go by. Also can you isolate the power from the amplifier sections for testing? To see if you will get the relay to click.



Barney
 
Looking it over right now.

Those are the copies I was talking about being rather dark and hard to see the board layouts.

Barney
 
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Check the fuses..
On page 14 step 1b. Check the Mid point potential (dc offset) on each amplifier assembly.
 
Fuses were all removed from the boards. Shows them to be 5A which I happen to only have two of the four needed. Placed in 1A fuses and still no click but fuses stayed OK.

So tomorrow if possible will check the voltages and adjust if need be.



Barney
 
I spent some time re-building one of those for my buddy.
They do use those wire caps originally, if that's your worry.

A common failure is the micro switchs in the A/B switch unit.
Some info here, http://www.tapeheads.net/showthread.php?t=19777

I ended up re-capping everything (since I was in there) except the power supply, replaced all the fusistors (all WAY out of spec and causing issues) and all the transistors on the filter board and tone board (noise).

The solder joints on the board in the back panel are also suspect.

Luckily these are pretty easy to tear nearly completely apart to work on.

Luck.
 
There is a fusistor at FR501 on the filter NA-06338 board (upper right corner of the schematic, off the B+).

Another one at FR301 on the tone board NA-06337 (middle bottom of the schematic, off the B+)

Look for others and check them all.
 
Fuses were all removed from the boards. Shows them to be 5A which I happen to only have two of the four needed. Placed in 1A fuses and still no click but fuses stayed OK.

So tomorrow if possible will check the voltages and adjust if need be.



Barney

Right now, just need to check for DC at the amplifier outputs*.DC wil prevent the protect relay from "setting". If no significant is present,then the issue is in the protect circuit or power supply.

* mid point voltage check!
 
I spent some time re-building one of those for my buddy.
They do use those wire caps originally, if that's your worry.

A common failure is the micro switchs in the A/B switch unit.
Some info here, http://www.tapeheads.net/showthread.php?t=19777

I ended up re-capping everything (since I was in there) except the power supply, replaced all the fusistors (all WAY out of spec and causing issues) and all the transistors on the filter board and tone board (noise).

The solder joints on the board in the back panel are also suspect.

Luckily these are pretty easy to tear nearly completely apart to work on.

Luck.
These will be addressed after troubleshooting the "root cause"...
 
There is a fusistor at FR501 on the filter NA-06338 board (upper right corner of the schematic, off the B+).

Another one at FR301 on the tone board NA-06337 (middle bottom of the schematic, off the B+)

Look for others and check them all.

ditto...
 
These will be addressed after troubleshooting the "root cause"...

The one I worked on had a bad micro switch so power was totally messed up to one amp. I don't think your going to get any reliable readings if one or both of those switches is out.

I would start with them to make sure you even have good power to the amps.

Easy to check, the lines are all along the top of the amps. Make sure you have a good ground on the meter.

It actually was the root cause. It took some adjustments on the amps after replacement to get the relay to click and hold.
 
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The one I worked on had a bad micro switch so power was totally messed up to one amp. I don't think your going to get any reliable readings if one or both of those switches is out.

I would start with them to make sure you even have good power to the amps.

Easy to check, the lines are all along the top of the amps. Make sure you have a good ground on the meter.

It actually was the root cause. It took some adjustments on the amps after replacement to get the relay to click and hold.

Perhaps it is...Lets get to that point methodically.
This isn't my first go-round..partner..
 
Perhaps it is...Lets get to that point methodically.
This isn't my first go-round..partner..

No disrespect intended at all. I've read and learned a lot from your posts.

Just pointing to a failure point that isn't obvious, in case you didn't know about those darn switches going out.

The readings I got when I started on the one here were quite confusing.
But it was my first A/B switchable unit. I spent a bit of time chasing my tail.
 
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