Hi,
I'm servicing an old integrated SU-V4 Technics amp. I already replaced one of the output IC stages but it seems that was not the only problem. I did some measurements and found out that there are 3 transistors around which I get strange voltage measurements. These two transistors are 2SC2631/2SC1953 (2 pcs.) and 2SK109. Does anybody know a substitute for these two. I would rather use European substitutes if they exists. I think the bigger problem is 2SK109 because is obsolete double transistor. I'm not sure if any company is still making this kind of transistors. Maybe it is possible to replace it with two transistors of the same type.
P.S: I wrote '2SC2631/2SC1953' because in the service manual it is written 2SC2631 and in the amp it is 2SC1953. It seems they used an equivalent already.
Sorry for my 'rusty' English.
Edit: I added a picture of these two transistors if someone found it useful.
I'm servicing an old integrated SU-V4 Technics amp. I already replaced one of the output IC stages but it seems that was not the only problem. I did some measurements and found out that there are 3 transistors around which I get strange voltage measurements. These two transistors are 2SC2631/2SC1953 (2 pcs.) and 2SK109. Does anybody know a substitute for these two. I would rather use European substitutes if they exists. I think the bigger problem is 2SK109 because is obsolete double transistor. I'm not sure if any company is still making this kind of transistors. Maybe it is possible to replace it with two transistors of the same type.
P.S: I wrote '2SC2631/2SC1953' because in the service manual it is written 2SC2631 and in the amp it is 2SC1953. It seems they used an equivalent already.
Sorry for my 'rusty' English.
An externally hosted image should be here but it was not working when we last tested it.
Edit: I added a picture of these two transistors if someone found it useful.
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For bipolars replacement, I am sure you can find plenty of suitable parts (including European). I will give you several numbers, staying with Panasonic parts:
2SC1953 S, or T - 1.2W
2SC5346 S - 1W
2SC2632 S - 1W
2SC2631 S - 0.75W
These are the same transistors, just different packages (power dissipation).
For (still can be found) 2SK109-D FETs replacement:
(u)µPA68H K2××, or L
2SK150 GR
M47F
2SK389 GR
2SC1953 S, or T - 1.2W
2SC5346 S - 1W
2SC2632 S - 1W
2SC2631 S - 0.75W
These are the same transistors, just different packages (power dissipation).
For (still can be found) 2SK109-D FETs replacement:
(u)µPA68H K2××, or L
2SK150 GR
M47F
2SK389 GR
2SK389 = N-FET (double)
2SJ109 = P-FET (double)
Replacement for 2SJ109 is 2SJ74, but you need two pieces, they should be thermally coupled with matched Idss.
Only BL grade
GR/BL/V grade
PS: Andrej, raje naroči uparjene, bo najmanj problemov.
2SJ109 = P-FET (double)
Replacement for 2SJ109 is 2SJ74, but you need two pieces, they should be thermally coupled with matched Idss.
Only BL grade
GR/BL/V grade
PS: Andrej, raje naroči uparjene, bo najmanj problemov.
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Thank you, stormsonic. I will use 2x2SJ74 in worst case.
P.S: Tudi sam bi najraje uporabil dvojne tranzistorje, ampak nevem če bom dobil nadomestnega. Trenutno iščem kakšno pametno (spletno) trgovino, ki prodaja predvsem japonske polprevodnike. Pri nas je itak vse skupaj bolj bogo. Imaš mogoče kakšen predlog?
P.S: Tudi sam bi najraje uporabil dvojne tranzistorje, ampak nevem če bom dobil nadomestnega. Trenutno iščem kakšno pametno (spletno) trgovino, ki prodaja predvsem japonske polprevodnike. Pri nas je itak vse skupaj bolj bogo. Imaš mogoče kakšen predlog?
Dear andrej123
I have two 2SK109 which I don't have any plan on using soon. The rank is C instead of D with Idss ~2.6 mA. I bought them almost 20 years ago in Akihabara. If you are interested, drop me a PM. I prefer to send both of them out, so I won't have just one in hand...
Regards,
Satoru
I have two 2SK109 which I don't have any plan on using soon. The rank is C instead of D with Idss ~2.6 mA. I bought them almost 20 years ago in Akihabara. If you are interested, drop me a PM. I prefer to send both of them out, so I won't have just one in hand...
Regards,
Satoru
Datasheet for 2SK109 :
2SK101-200
The closest replacement in terms of Vds, Yfs and Cis is 2SK209 (in Y, GR & BL grades).
But these are single N-JFETs in SMD and not dual matched.
So you need to match and use an adaptor PCB.
BL grade is in stock at Mouser.
There is also a dual version of 2SK109, namely 2SK2145 which is also available at Mouser.
However this has a Common Source connection so is only useful if your circuit is wired as such (e.g. diff pair with no source degeneration).
If Vds & Cis are not imprtant, I would just use LSK389 (comes in 4 different Idss grades) which is relatively easy to get.
Patrick
2SK101-200
The closest replacement in terms of Vds, Yfs and Cis is 2SK209 (in Y, GR & BL grades).
But these are single N-JFETs in SMD and not dual matched.
So you need to match and use an adaptor PCB.
BL grade is in stock at Mouser.
There is also a dual version of 2SK109, namely 2SK2145 which is also available at Mouser.
However this has a Common Source connection so is only useful if your circuit is wired as such (e.g. diff pair with no source degeneration).
If Vds & Cis are not imprtant, I would just use LSK389 (comes in 4 different Idss grades) which is relatively easy to get.
Patrick
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