View Full Version : Sansui 9090 Restoration


Raccoon1400
09-30-2012, 09:23 PM
Got my hands on a sansui 9090 to restore.
Needs:
-new outputs. Someone rebuild one channel with outputs rated for half the power of the originals. (I can use MJ21194?)
-AM antenna missing
-needs new jumpers, will make them out of brass rod
-relamp (will get bulbs from dgwojo)

I am planning on doing a full recap/restore.

What filter caps should I use?

Anyone have suggestions?

avionic
09-30-2012, 09:36 PM
(I can use MJ21194?)

Sure can..Or MJ21196G's

Robisme
09-30-2012, 10:58 PM
What filter caps should I use?

Anyone have suggestions?

I just recapped a 9090 for someone and used these (http://www.digikey.com/product-search/en?x=15&y=12&lang=en&site=us&KeyWords=P10646-ND).

I am sure there are better, but these fit perfectly and work fine.

Rob

avionic
09-30-2012, 11:29 PM
I just recapped a 9090 for someone and used these (http://www.digikey.com/product-search/en?x=15&y=12&lang=en&site=us&KeyWords=P10646-ND).

I am sure there are better, but these fit perfectly and work fine.

Rob

The price is right..:thmbsp:

kevzep
10-01-2012, 12:04 AM
-new outputs. Someone rebuild one channel with outputs rated for half the power of the originals. (I can use MJ21194?)


What have they put in there? Curious minds are active here.....

The suggestions made by avionic are of course exactly right.....

Raccoon1400
10-01-2012, 09:27 AM
What have they put in there? Curious minds are active here.....

The suggestions made by avionic are of course exactly right.....
toshiba 2SD371. Rated 50W instead of 100W.


I could use the panasonic filter caps, but does anyone know if there are better ones I could use?

aileenamegan
10-01-2012, 01:40 PM
Instead of brass or steel jumpers use short, quality cinch/RCA cables. Better contact.

DCinDC
10-01-2012, 01:50 PM
If the power switch still works, parallel both sets of terminals to double the current capacity.

There is a flaw in the 9090, where if the protection relay opens the amp's output is shorted to ground. Search on dr8audio posts to find it.

I'm doing another one now, too.

dr*audio
10-02-2012, 07:22 PM
Here is everything you need to know.
http://www.audiokarma.org/forums/showthread.php?t=117552

Raccoon1400
10-06-2012, 11:32 AM
Here is everything you need to know.
http://www.audiokarma.org/forums/showthread.php?t=117552

Thanks! Exactly what I was looking for.

Raccoon1400
10-24-2012, 03:21 PM
Looking at the driver board, someone has been messing with it. Some components are on the back. Not sure what is supposed to be how it is, or what has been hacked. Also note the resistor going from R43 to R55. Is it supposed to be there, or should R43 and 55 be there instead?
One of the bias devices has been replaced, I would like to replace both. What part is best?
Also I see a couple gumdrop diodes to replace.
Are there any fusistors?

EchoWars
10-24-2012, 04:44 PM
Looking at the driver board, someone has been messing with it.This is typical Sansui factory 'Oops!' work. If you work on Sansui gear for any length of time, you get used to seeing it.

Raccoon1400
10-24-2012, 05:07 PM
This is typical Sansui factory 'Oops!' work. If you work on Sansui gear for any length of time, you get used to seeing it.

Lots of signs of hacking in this unit, including
-outputs replaced with ones rated for half the power
-a couple broken traces on the driver board
-one of the fuses was replaced on driver board
-a couple caps replaced on input selector board


How much of that do you figure was from the factory? They wouldn't have blown it up at the factory, or would they?

yellowbee
10-24-2012, 05:10 PM
Looking at the driver board, someone has been messing with it. Some components are on the back. Not sure what is supposed to be how it is, or what has been hacked. Also note the resistor going from R43 to R55. Is it supposed to be there, or should R43 and 55 be there instead?
One of the bias devices has been replaced, I would like to replace both. What part is best?
Also I see a couple gumdrop diodes to replace.
Are there any fusistors?

look original...from Sansui factory

except for the fuse on the back...
might be original too.

naderpe
10-24-2012, 07:40 PM
It's original Sansui factory build
look original...from Sansui factory

except for the fuse on the back...
might be original too.

Raccoon1400
10-25-2012, 08:15 PM
Recapped most of the tuner board, now I can't get the tuner to do anything, am or fm. No meter movement or sound. Checked for bridged solder, backwards caps, didn't see anything. I lifted the front end as shown in the thread dr*audio linked. Thought maybe a wire came loose but can't find one. Any suggestions?

dr*audio
10-26-2012, 06:42 AM
Check the power supply for the tuner. It's that little board on the left front. The resistor and transistor like to desolder themselves.

Raccoon1400
10-26-2012, 09:29 AM
Check the power supply for the tuner. It's that little board on the left front. The resistor and transistor like to desolder themselves.

Looked fine, but I touched up a few joints. Still nothing.

dr*audio
10-26-2012, 11:19 AM
Looked fine, but I touched up a few joints. Still nothing.

Measure the voltage...

Raccoon1400
10-26-2012, 12:55 PM
Measure the voltage...

The 8V supply is working, but I am getting <1V on the 35V supply. When I disconnect the board, the supply reads as it should. As far as I can tell nothing is shorted on the board, or bridged.

Haven't recapped this board yet.
And it was working great before I recapped the tuner board.

I suppose the next thing would be to disconnect the regulator board from the tuner board and measure the voltage again? I will try that when I get home.

Sam Cogley
10-26-2012, 02:45 PM
Sounds like you got something messed up on the tuner board. Check to make sure you got all the caps in the right way.

Raccoon1400
10-26-2012, 04:21 PM
Fixed it!
Disconnected 12V supply from tuner board, and still no voltage.
Followed the other wires back to the selector switch, and cleaned it. Back in business.

Now what to do with the driver board? Anyone have parts suggestions?
And what about the resistor going from where R43 should be to where R55 should be? Is it supposed to be that way, or should there be R43 and R55?

Raccoon1400
10-28-2012, 09:12 PM
I'd like to replace the switch, it is starting to go. What is the best replacement?
Also, what is the best part to replace the bias diode?

Other that those parts, everything is pretty much covered.

Raccoon1400
11-12-2012, 10:41 PM
It is up and kicking!
Lamps, all the caps, relay replaced, new power switch, new onsemi outputs, etc.

Thanks again to dr*audio for providing much useful help.

:music:

VintagePlus
11-12-2012, 11:20 PM
Good job! Any pics of that sweet 9090?

Raccoon1400
11-13-2012, 12:05 AM
Good job! Any pics of that sweet 9090?
:smoke:

tiga
11-13-2012, 05:07 PM
Nice work! My refurbed 9090 is my favorite piece in my small but loveable collection of vintage audio. It's just a wonderful receiver with a great sounding amp section. It makes everything sound better....:music: