Hi!
I'm restoring a Sony TA-F6B amp(European model), the power supply kicked out the bucket. A cap at the regulator part blown up(C604), I guess this caused some transistors' death around it.
Already replaced all electrolytic caps, desoldered and measured all transistors, I still have to check all resistors and diodes(but at first look they seems to be fine).
The original 2SC2023-Os at the inverter are fine, also Q605, Q606, Q607, Q608 are ok.
The problem in the regulator part is with an R hFE grade 2SC2023 (Q613), 2SC1810 (Q602), 2SA911 (Q603). I suspect the that I should change all transistors in the regulator, at least Q601/Q613 to the same.
I have a few 2SC2023 (without R or O letter) but still doesn't find any info about the original R/O hFE ranking, so I think i should use the lowest hFE for that pair. The ones I have had hFE from 43 to 92, but none of them has the same.
Also if I change 601/613 to 2SC2023, would it affect the other part of the power supply?(sadly I don't have that kind of deep knowledge about SMPS/PLPS)
Found some datasheet for 2SC1810 and 2SA911, but I'm not sure about the substitutes. I can't find any that has the same 12V max Veb, just 5V-6V-9V (is it important?)
It would be a really big help if someone could advice some replacements for 2SC2023R, 2SC1810, 2SA911. Maybe I could get some new old stock from the last two from eBay, but I would prefer some common off the shelf part, I don't trust these "new-old" parts from unknown source.
Attached the schematic from the service manual, marked the bad transistors.
I'm restoring a Sony TA-F6B amp(European model), the power supply kicked out the bucket. A cap at the regulator part blown up(C604), I guess this caused some transistors' death around it.
Already replaced all electrolytic caps, desoldered and measured all transistors, I still have to check all resistors and diodes(but at first look they seems to be fine).
The original 2SC2023-Os at the inverter are fine, also Q605, Q606, Q607, Q608 are ok.
The problem in the regulator part is with an R hFE grade 2SC2023 (Q613), 2SC1810 (Q602), 2SA911 (Q603). I suspect the that I should change all transistors in the regulator, at least Q601/Q613 to the same.
I have a few 2SC2023 (without R or O letter) but still doesn't find any info about the original R/O hFE ranking, so I think i should use the lowest hFE for that pair. The ones I have had hFE from 43 to 92, but none of them has the same.
Also if I change 601/613 to 2SC2023, would it affect the other part of the power supply?(sadly I don't have that kind of deep knowledge about SMPS/PLPS)
Found some datasheet for 2SC1810 and 2SA911, but I'm not sure about the substitutes. I can't find any that has the same 12V max Veb, just 5V-6V-9V (is it important?)
It would be a really big help if someone could advice some replacements for 2SC2023R, 2SC1810, 2SA911. Maybe I could get some new old stock from the last two from eBay, but I would prefer some common off the shelf part, I don't trust these "new-old" parts from unknown source.
Attached the schematic from the service manual, marked the bad transistors.
