Couple years ago i bought a defective (i didnt know at that time..) sansui au-519. When I first plugged it in, i saw the red blinking light.. that didnt seem too good. Of course..no sound came out of my speaker, i was very disapointed of my 35$ amp. Anyway.. i made a few research and turns out its a great amp! But it is not working.. Life was very busy so it just got stored into the basement for approx 8 years.. Now i am partially unemployed (free time!) so i decided to try to fix it!
After cracking it open, there was a blown fuse. Oh.. it might be just that! so i replaced the fuse .. and it blew again! Oh no. So i did more testing (my electronic skill arent very good, but i love to learn) So i searched how to test transistors.. diodes .. Grabbed my multi meter and focused on the board that was connected to the same side that the fuse was blown. I found a bad output transistor 2sc2580, So I ordered a pair of transistor to replace it, which i have not received. The said board is the f-2927. As i red on the forum, they usualy take other component down with them when they blow. So i used the other channel to compare reading (even they are not exactly the same) they sure look a like. I found that i get different voltage drop from the TR16 on the F-2627 than on the other one.
I am getting
c-b = 0.37v
c-e = 0.1v
and the other board i get
c-b = 0.47v
c-e = 0.51v
but when its pulled out of the board i get around 0.7 for both readings..
After cracking it open, there was a blown fuse. Oh.. it might be just that! so i replaced the fuse .. and it blew again! Oh no. So i did more testing (my electronic skill arent very good, but i love to learn) So i searched how to test transistors.. diodes .. Grabbed my multi meter and focused on the board that was connected to the same side that the fuse was blown. I found a bad output transistor 2sc2580, So I ordered a pair of transistor to replace it, which i have not received. The said board is the f-2927. As i red on the forum, they usualy take other component down with them when they blow. So i used the other channel to compare reading (even they are not exactly the same) they sure look a like. I found that i get different voltage drop from the TR16 on the F-2627 than on the other one.
I am getting
c-b = 0.37v
c-e = 0.1v
and the other board i get
c-b = 0.47v
c-e = 0.51v
but when its pulled out of the board i get around 0.7 for both readings..