Where do I start?

[gyrene]

Holy Crap...so much information in these threads.
Guess I'll start by saying I run two Sansui's.
One is the 9090 and the other is a 4000.The pic in the avatar is the 4000 with a dead mouse lodged up in the bar antenna region.As I found it the day I bought it.P.O.claimed it did not bring in a signal anymore like it used too.Whatdayathingkadat?
Both are probably 35 years old and I love them.
They power a set of Klipsch KG4's.
And I love them.
I like older stuff mostly.
I don't mind cleaning something up and tuning it up and having it look great and sound great too.
Same with my motorcycle.1992 FLTCU.Big fat Tour Glide by Harley Davidson.
Love it.
So I have the sansui 4000 in use but I'd like to post some pics of the innards and get some opinions of how it looks to you guys.
Some of the solder joints don't look to great.Lets say they'd not pass inspection back when I was in solder school.But I don't have any symptoms that I notice so I'm hesitant to do anything to it.
I'll try to post the pics in the next hour or so.Being such a dinosaur it'll take me a while to get them posted.
Meanwhile what are your opinions on the Sansui 4000?
45 nice clear watts per channel at 8 ohms all day long.The volume knob never goes past 9 o'clock position due to the efficency of the Klipsch KG4's.
Pulls in radio stations nice and strong like I remember from back when Cousin Brucie was broadcasting.

Check out some of these solder joints.They seem to work fine despite their marginal look.

[gyrene]

This is the Sansui 4000 basic innards shot.

[gyrene]

Took one board out and found this tough brown crusty growth on one transistor.What do you think? Should I clean that stuff off? If so...how?

[gyrene]

Is this corrosion? or what? Does it have to get cleaned off? Again...how?What product and method?

[Jon_Logan]

The "crusty growth" is just adhesive to attach the bias diode onto the driver transistor. It's fine, not dangerous. Just make sure that it's not touching any bare wires. Scrape it off if you see it touching the bare wires. Some of those adhesives can become conductive over time.

[gyrene]

Thank you Jon.Same with all the crusties?

[Jon_Logan]

They are better removed, for peace of mind.

[speaker dave]

Originally Posted by gyrene

Is this corrosion? or what? Does it have to get cleaned off? Again...how?What product and method?

The brown rings around each solder joint are the rosin that was present in the solder. Rosin helps make the solder joint, it lets the solder flow and "wet" the surface even if the surfaces aren't perfectly clean. You can clean it off with some nasty solvents but it won't make any difference to the opperation of the unit.

David

[gyrene]

Got it.I'll live with it.Thanks sd