9090 Selector Switch Capacitor

[robdunn]

Hi all. I just bought a 9090 that needs some work. It needs a good cleaning, but has already been recapped. I am noticing on the selector switch there is a capacitor that seems to be missing. On the bottom side of the board where the selector switch is soldered on, I see pictures showing a capacitor soldered between the second and third pin, but I cannot find any reference for what it should be. It appears that the third pin would only get feed through that Cap, since the point on the board goes nowhere. Can someone help? I hope I explained this clearly enough.

 

[Hipocrates]

Hi all. I just bought a 9090 that needs some work. It needs a good cleaning, but has already been recapped. I am noticing on the selector switch there is a capacitor that seems to be missing. On the bottom side of the board where the selector switch is soldered on, I see pictures showing a capacitor soldered between the second and third pin, but I cannot find any reference for what it should be. It appears that the third pin would only get feed through that Cap, since the point on the board goes nowhere. Can someone help? I hope I explained this clearly enough.

Hello, welcome to audiokarma.

Do you have a picture? I'm looking on mine and I can't see it.

 

[tnsilver]

It's in the SM (page 16).
It's a 1uF/50V EC cap which is a PITA to get to as it requires total removal of the F-2597 connector circuit board.
If you get to it, perhaps move it to the other side so it would be easier in the future.

 

[robdunn]

Hello, welcome to audiokarma.

Do you have a picture? I'm looking on mine and I can't see it.

I found some pictures online for reference, and I took some pics of mine. You can see the cap in the pic named "9090 bottom", and it is missing in mine. Thanks for the help.

 

[Hipocrates]

Yupe, no present on mine. That board is the F-2541 (Eq board), bbut that cap seems to be a 1uf 50v e.c.
I have the service bulletin requested on the other thread but I can't upload it because is too big, I can send it to you by email if you wish.

 

[tnsilver]

OK, now with the pictures it's more clear. Yup, I got it too. Same as before. 1uF/50V EC but undocumented.

 

[Hipocrates]

Yup, I got it too

I wonder what it does

 

[tnsilver]

I'd guess it's a snubber that was added once loud pops and clicks were reported between function switching...

 

[robdunn]

OK, now with the pictures it's more clear. Yup, I got it too. Same as before. 1uF/50V EC but undocumented.

 

[robdunn]

Thank you, thank you, thank you. You guys are all heaven sent. This is a great resource that just does not exist elsewhere. I look forward to spending more time here, and learning more. Is there a section somewhere that I can learn the ins and outs of the whole site. There is a lot here.

I'd guess it's a snubber that was added once loud pops and clicks were reported between function switching...

That makes sense.

 

[robdunn]

Yupe, no present on mine. That board is the F-2541 (Eq board), bbut that cap seems to be a 1uf 50v e.c.
I have the service bulletin requested on the other thread but I can't upload it because is too big, I can send it to you by email if you wish.

That would be great...robdunn@rogers.com

 

[Skywatcher]

I have noticed Sansui tends to have components numbered in the 9xx range that are mounted on the back of boards, are listed, but not actually designated or have a silkscreen marking. Things for example R901, R902 that are on the F-2624 driver board and mounted on the back.