Dear All,
My Sansui B2101 suddenly stopped producing sound. The display bars works, meaning peak levels up and down with a pre input. I have checked all the outputs are fine. About 300mV is in the speaker terminals. I checked the DC offset (see SM attached image) and have found that DC voltage in Step 1 (for L ch) in Table 2.1 in SM about 2v but 0mV in R ch (step 2). I have recapped the L and R both F4618 and replaced one UPA68H (bought from eBay) in L ch. Now the L ch is 0mV, meaning that I have completed Table 2.1 smoothly. However, I am struggling in Table 2.2.
Table 2.2: Steps 1 to 4 are not achievable. The voltage is not stable at all, drifts a lot, goes to 600mV then shows OL in my Fluke 116. This is the same for the both L and R ch. I have sprayed Freezing spray on the both UPA68H and 2sc2291, but still the voltage does not stabilize.
Am I missing to check any resitors/diods or transistors?
I have read some forum in AK and Diyaudio such as (https://audiokarma.org/forums/index...zy-10v-and-something-missing-on-board.790817/)
Please help me if you can.
Thanks in advance.
My Sansui B2101 suddenly stopped producing sound. The display bars works, meaning peak levels up and down with a pre input. I have checked all the outputs are fine. About 300mV is in the speaker terminals. I checked the DC offset (see SM attached image) and have found that DC voltage in Step 1 (for L ch) in Table 2.1 in SM about 2v but 0mV in R ch (step 2). I have recapped the L and R both F4618 and replaced one UPA68H (bought from eBay) in L ch. Now the L ch is 0mV, meaning that I have completed Table 2.1 smoothly. However, I am struggling in Table 2.2.
Table 2.2: Steps 1 to 4 are not achievable. The voltage is not stable at all, drifts a lot, goes to 600mV then shows OL in my Fluke 116. This is the same for the both L and R ch. I have sprayed Freezing spray on the both UPA68H and 2sc2291, but still the voltage does not stabilize.
Am I missing to check any resitors/diods or transistors?
I have read some forum in AK and Diyaudio such as (https://audiokarma.org/forums/index...zy-10v-and-something-missing-on-board.790817/)
Please help me if you can.
Thanks in advance.
