sansui 5050 rebuild

[benshi]

hi again Sansui friends
i have a questions for you
i did a total rebuild to my 5050
i but a kit with instruction
in the instruction is said that on the power supply board(i have f2701 board)
"in r610/r611 you will either see two small resistors or two large resistors there, if you have small resistors (the same size as the 6.8 ohm that you replace) check the board underside and you'll probably see two more small resistors there if you have large resistor, you can leave these alone. if you have small ones on boat sides, remove all of these, then replace the ones on the top with the new 2.2 ohm resistors. you don't need to replace the bottom ones, just to remove them"

in my board in r610/r611 i have small resistors( it's look the same size as the 6.8 that i replaced) and in the backside i don't have resisters at all in r610/r611

someone can help me to understand what to do here?

i have two resistors left - 2.2ohm that i don't understand what to do with them

i put some photos
thanks for your answer, benshi

 

[Leestereo]

On the F-2701 board, the equivalent 2.2ohm resistors are at R612 and R613.

 

[benshi]

hii thank you for your help!

i have a little new issue...
when i tern on the receiver on low volume only...
the sound not sounds good from the left speaker and when i turn up the volume its come back to life and its sounds good.
if after that i turn up the volume i low it again its sounds good.
its feel like the left side need to wake up and after i tern up the volume is alive
someone have an idea ?

 

[mrk229]

hii thank you for your help!

i have a little new issue...
when i tern on the receiver on low volume only...
the sound not sounds good from the left speaker and when i turn up the volume its come back to life and its sounds good.
if after that i turn up the volume i low it again its sounds good.
its feel like the left side need to wake up and after i tern up the volume is alive
someone have an idea ?

Did your kit include the speaker protection relay? What you describe is a classic symptom of dirty/oxidized relay contacts. You can try tapping on the relay case when it is acting up and see if it changes.

Have you cleaned the speaker selector switch?

 

[benshi]

Yes the kit included the big omron relay
And yes I cleaned all the switches
It’s not acting like it’s have any connection to the switches
They are not noisy
I will try your recommendation today and I will let you know
Thanks a lot

 

[benshi]

Hi again
I tried to tap on the relay it’s not make any difference.
Do you know if transistors can act like that sometimes?
Because it’s sometimes happens and sometimes not…
on the driver board the 4 transistors 2 for each Chanel if they doesn’t match it’s something that can do that kind of problem?

 

[kwayde]

Possibly a poor solder joint or open trace, something like that.

You say it happens sometimes, sometimes not. When it happens, take a dowel or something similar and start probing, tapping, or slightly push on the boards to see if you can find an area that makes it work/not work.

In your second pic I see plenty of poor solder joints that need attention. I circled just a couple areas but all of your work should be gone over to see if any joints are poor or shorted.
I enlarged this photo and many of those solder joints have rings around them telling me they have bad connections.