I'm new to the forum and have owned my Sansui 1000X since I was 17 in 1971. You can do the math. About 8 years ago the left channel started to distort and was weak. So it went to the basement...until now.

I know its low end entry Sansui and not worth putting much $ into but my initial cost is pretty low, 36 years of use and storage. So as I work to figure out what is wrong I'll post up pictures and info and of course be asking a lot of advice. Even if I never figure it out it will still be an adventure.

I powered it up and everthing seems about the same as when I stored it away. From my reading it seems the first thing to do is a good cleaning with Deoxit so I pulled the case off and got it ready.

Pictures and specs soon.

A bunch of people here really like the 1000 series. The X model was the last variation in that run.

Cleaning the controls may be all it takes to revive it. You need to spray the deoxit into the controls so it can work on the contacts inside. Let us know how it works out.

- Pete

left channel started to distort and was weak. the first thing to do is a good cleaning with Deoxit so I pulled the case off and got it ready.

Pictures and specs soon.
Don't forget to check the protection fuse at the rear panel

Good point Stene. Put a dab of dioxit on the fuse contacts too.

- Pete

Good for you, that unit deserves some TLC after serving you faithfully for so many years.
Lower power Sansui receivers are a passion to many folks, and those units sound excellent.
Ok, they won't really drive power hungry speakers to ear bleeding levels, but who wants ear bleeding anyway.
Casey:banana:


Oh, and welcome to AK!

the amp board has 4 pots.
the 2 larger ones adjust the output current and only need a multimeter across the quick acting fuse.
the 2 smaller white ones adjust the output and need an oscilliscope and dummy load.

I'm up for the first one but not the second.

The question is.. should I clean these pots with deoxit or leave them alone???

I would not clean them unless you are prepared to do the setup adjustments on the amplifier.

Using an ammeter, measure the bias current as stated in the service manual. if it is too low or high (more than 5ma off) after 10 minutes, then I would clean the large pots (bias pots) while noting their original position, then perform the bias setup procedure.

Thanks
Stay tuned for more.

Still working on my Sansui 1000X

This reciever has a distortion in the left channel that as the volume goes up it starts to sound clipped or buzzy.

Actions:
deoxit everything, including the edge connector of the amp board, fuses, output transistor pins and sockets, selector switch, volume, tone and balance pots

distortion still in left channel

reverse output from pre-amp to amp -- distortion stays on the same side--problem must be in main amp and output.

exchange output transistors TR051 and TR052 as noted in picture in service manual---Distortion changes sides and sound exactly the same but in the right channel!!! :yes:

I have not checked the current adjustment yet which I suspect I should do before or as part of installing new output transistors

Question The transistors are Toshiba 2SC494. An alternate part ID in the service manual is 2SD260. What is a good recommended replacment??

If you swapped the outputs and the problem follows to the other channel, then you've found part of the problem.

However, if one or more of the output transistors have failed in that channel then it may have damaged the driver transistors as well The drivers IIRC are the 2SA606 and 2SC959. Also look around for burned resistors in the driver circuit and check to see if the emitter resistors are OK. Some times they will overheat and open if an output transistor fails.

YOu won't be able to find the driver transistors in the original package style. THe little round metal "flying saucer" package style (yes, I don't know the style)was discontinued long ago. YOu will more than likely need to adapt a newer package style and add a small heatsink to it.

Someone here may be able to help you find a sub for your outputs and driver devices. I'm without a transistor manual at home, otherwise I'd be able to help you

Was traveling for the weekend and will take a look at everthing you suggest.

Dango

The drivers IIRC are the 2SA606 and 2SC959.

YOu won't be able to find the driver transistors in the original package style. THe little round metal "flying saucer" package style (yes, I don't know the style)was discontinued long ago. YOu will more than likely need to adapt a newer package style and add a small heatsink to it.

Someone here may be able to help you find a sub for your outputs and driver devices.
2SA606 substitute = 2SB631K
2SC959 substitute = 2SD600K

Note: Pin configuration