Sansui 9090 receiver

[Tomcow]

Sansui 9090.What transistors can replace C-5802 and the one transistor on the protection board that is red in color and appears to have 27 something on top and the number 1000 underneath??

 

[sanjib]

Can you post the pic of boards with the transistors you mentioned? I can't recall such transistors on Sansui 9090 (I may be wrong)!

 

[ivandezande]

This is easily top ten vaguest posts I've seen on AK.

 

[Tomcow]

Can you post the pic of boards with the transistors you mentioned? I can't recall such transistors on Sansui 9090 (I may be wrong)!

 

[Tomcow]

The 2 small transistors are C-5802 and the red one,can’t tell.

 

[sanjib]

Originals and possible replacements

TR01 - 2SC1211 - KSC2383
TR02 - 2SD313 - MJE15032
TR03 - 2SC1211 - KSC2383

 

[Tomcow]

Thankyou.

 

[sanjib]

Thankyou.

BTW, it is the power supply board, not the protection board.

 

[LBPete]

Why do you want to replace it?

- Pete

 

[Tomcow]

I’m talking about the main filter caps. I would like to add a resistor across each cap,so When and if I have to work on the receiver I don’t get electrocuted

 

[LBPete]

Huh? I thought we were talking about transistors on the power supply board.

- Pete

 

[Tomcow]

2sc-2383 transistor pinout is ECB.2sc-1211 transistors go EBC.Can I just follow the markings on the Sansui board??

 

[LBPete]

I would never trust the marking on the board without verifying them first. You still haven't said why you want to replace them.

- Pete

 

[Tomcow]

Two fuses were blown on the board.I’m pretty sure the above mentioned transistors are bad.Receiver is in protect mode.All output transistors are good.I just don’t want to put the 2383 transistors in wrong

 

[Tomcow]

Does anyone know if a Sansui 9090 receiver will still relay on or not with the small center board mounted in the middle with the metal cover over it is removed?Doing some troubleshooting.My friends 8080db will still relay on with the pin center board removed.Thanks.

 

[LBPete]

OK, one thing at a time. Are you working on a 9090, 9090DB or 8080DB? The 9090 has a completely different amplifier circuit than the 9090DB or 8080DB.

Assuming you are working on the 9090 in the title of this thread, what two fuses on the attached diagram were blown? It's likely you have blown output transistors.

The board mounted vertically on the power supply board is called the driver board. It's held in place by a tin bracket. Whether or not it comes out of protection with that board removed depends on the fault tripping the protection circuit. If the fault is on the driver board, it should come out of protection with that board removed. If you have blown output transistors it may not come out of protection with the board removed. In that case you may have problems with the driver board caused by the blown output transistors.

- Pete

 

[Tomcow]

Hi Pete I am working on an Sansui 9090. As far as I can tell all 8 output transistors are good.The driver board definitely has some bad fuse resistors on it.I Will work on that later. The two fuses closest to the big metal what I assume are Zenor diode‘s,were blown (6 amp)I replaced both c-1211 transistors and also Tr-02,as they were bad.I have 2SC 2383 to replace the C 1211’s.I replaced tr-02 with D-313. The thing that is puzzling me,the C1211’s pinout is EBC,but the board reads,ECB.the 2383’s pinout is ECB.All 8 output transistors are the same and I get .53 readings two ways tested on all 8.Tom

 

[LBPete]

Those gray metal diodes next to the fuses are the rectifier diodes. They are not zeners. If those two fuses next to them were blown, it's almost certain you have blown output transistors for the left channel. You say the outputs are OK, how did you check them? You also may have fried the contacts in the protection relay. You should look carefully at them too.

You appear to be randomly changing parts and I'm trying to get you focused on what you actually need to look at. The transistors you seem so intent to change have nothing to do with the blown fuses.

- Pete

 

[Tomcow]

I removed all eight transistors FROM their mounts and checked each one individually.They are all identical.I got .53-.55 readings testing each one,got those readings measuring 2 different ways.

 

[Tomcow]

I will take my time with it and I will Eventually get it working.