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Sansui 6060 Output Issue

Hello,
I've had my 6060 for a while, and today the speaker outputs seem to have gone on me. First, it stopped playing in stereo, then just got up and quit completely in Mono also. My speaker set up is good.
I have a basic understanding of electronics, but really need help with this one. I want to repair this amp. Any help would be greatly appreciated. Thanks



Sansui 6060 Output Issue

Neil_Ryan,
While I don't have a 6060, I do have a number of 8080's and 9090's, which are from the same era in time. these units are usually easy to repair and restore.
A common problem is the regulator power supply transistor (2sd313) overheats and fails. This regulator supplies DC voltage to the am and fm sections RF, IF amd MPX. I notice you said that first it stopped playing stereo and then wouldn't play mono. If you no longer get any fm signal strength center tune, or stereo light, then I would check the regulator and its connections which may be burnt. But if this is your problem, then you should be able to play a tape deck through the tape inputs and hear sound as the regulator only affects am and fm.
If you are "tuning" and getting signal strength, I would look at the driver stages for the output amp. Sansui used fusable resistors as protect devices in the units that either change in value or open with age. This is the most common problem I have seen. When these resistors change in value or open, the protect relay won't engage and you get no sound. The resistance values are usually 4.7 ohm, 10 ohm, 22 ohm, 33 ohm, 39 ohm, 47 ohm, 100 ohm, up to 820 ohm. They do not have a glossy finish as the other resistors do. They usually have a greenish yellow/tan appearance are are typically 1/4 to 1/2 watt. You may want to check their resistance both directions (use the highest resistance reading you find in circuit) I always replace all of these with high quality carbon composition or metal oxide ones anyway.Also check the outputs and drivers, but I rarely find issues with them, providing the right fuses were used in the unit.
Hopefully this helps
Tom

Sansui 6060 Output Issue

Hi Neil_ryan, I just went through this with my 7070, I also have a pretty good understanding of electroincs but i decided to take it to a friend of mine he is a tech. Well after he went through it while i was there it turns out that the whole power supply, amp board and various other thing we fried. The only explanation he had was that the person i bought it from must have drove it very hard with four speakers and and also do to it's age it was just a matter of time before it died. So know it sits in my shop as a donor unit. If i were you i would down load the 6060 service manual and start checking the output transistors, drive resistors, power supply, ect unit you find the problem. Hope this help in some way.