Yamaha B-2 restoration journey

No... There are 3 NPN's per board and 5 PNP's per driver board.

6 -2SC's and 10- 2SA's total.
 
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And what about the green capacitors C121 and 120, can I use Panasonic ECW Polypropylene caps for them?
 
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What even weirder is, is C114, that should be a 100 uF bipolar cap, but he used 2 polar 220 uF caps in series (positives connected). Not sure what that tells me :dunno:

he was prolly out of 100uf caps. :) The two 220's are essentially 110uf. Look up series capacitance.
 
They should fit ok. Not a whole lot of room to work with once the boards are installed into the unit.
 
he was prolly out of 100uf caps. :) The two 220's are essentially 110uf. Look up series capacitance.

I would look for a proper 100uf BP cap, if one of the polar caps goes bad, POOF, can happen in the rest of the circuit.

I use this as temp solution till I get the proper BP cap in stock.

Nashou
 
I would look for a proper 100uf BP cap, if one of the polar caps goes bad, POOF, can happen in the rest of the circuit.

I use this as temp solution till I get the proper BP cap in stock.

Nashou

The nichicon muze would ba a good choice, unless you want to go for 105deg. That area is well ventilated tho.

Yes, I have already 2x Nichicon ES 100 uF 10V in the BOM :thumbsup:

Just a word of caution. Pin out needs to be very carefully observed when installing the replacements. One slip up could end in tears for the VFET's.

Thanks for the heads up. I'm planning on making notes and measure which is emitter, base and collector for both old and new. Reading data sheets will not be enough as I've read in other threads.
 
No... There are 3 NPN's per board and 5 PNP's per driver board.

6 -2SC's and 10- 2SA's total.
Shoot, someone beat me to it and ordered 10. Now there are only 9 left and I need 10. Must've seen this thread :biggrin:

Quickly ordered the Mouser BOM in order to secure the 9. Double double checked everything. Also pushed the button on Digikey for the large CDE cans and the heat sinks. Both free shipping :naughty:
 
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Definitive BOM:

Power board


C205 & 206 Nichicon UPW2C101MHD
C209, 210 Nichicon UPW1H100MDD
C213, 214 Nichicon UPW2A100MED
C215 & 216 Nichicon UHE2A151MHD (DIGIKEY) 150 uF according to AK, 100 uF UHE2A101MPD according to schematic. Ordered both.
C219 Nichicon UPW1E471MPD
C223 Nichicon UPW1C101MED1TD
C220 & C221 Nichicon UVZ1C100MDD1TD
C227 & C228 Nichicon ES 10 uF 50V -> In stock
C225 & C226 Panasonic ECW Metalized film ECW-FD2W225JB

TR203, 204, 215 & 219: 2SC458C -> KSC1845

D205, 206: Zener Diode EQB01-30 -> BZX85C30
D210: Zener Diode WZ-130 -> BZX55B13-TAP

Filter Caps: 4x Cornell Dublier 22.000 uF 383LX223M080B092VS DIGIKEY

Speaker relays: Omron LY2-0-DC12 Z978-ND

Driver board:

C114 Nichicon ES Bipolar 100 uF / 10V UES1A101MPM (2x)

TR110, 121 en 123 2SC1452 -> 2SC3902T (x2)
TR107, 108, 109, 122 en 124 2SA810 -> 2SA1507T (x2) -> only 9 available!
16 TO-126 heat sinks DIGIKEY HS216-ND

C120, 121 & 122 0,022 uF 100V (x2)

All fuses

DC Balance + Bias + 85V pots

VR101 (x2) Bourns 3362W-202LF-ND (single turn)
VR102 (x2) Bourns 3362X-104LF-ND (single turn)
VR201, 202 Bourns 3362R-502LF-ND (single turn)

Meter board

C303 / C304 470uF / 6.3V Nichicon PW UPW1A471MPD
C307 / C308 220uF / 50V Nichicon PW UPW1H221MPD
C311 / C312 1uF / 50V Nichicon PW UPW1H010MDD
C317 / C318 6.8uF / 35V Nichicon PW UPW1V6R8MDD
C319 / C320 100uF / 50V Nichicon PW UPW1H101MPD
C323 10uF / 50V Nichicon PW UPW1H100MDD
C326 / C327 100uF / 80V Nichicon PW UPW2A101MHD
C322 / C321 / C324 / C325 47uF / 50V Nichicon PW UPW1H470MED

TR305, 306, 309, 310, 311, 312 & 319 till 322 2SC458 -> KSC1845FTA
 
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Yes that duo is usable; and it does have some better specs than the ones you referred to before.

As for ranking; high gain transistors are mandatory for TR107/108 (rank T thus).
Also to be matched within 5% of each other (you need a bunch of them)

TR109/110 either ranks T or S.

For the driver trannies, they have little voltage gain functionality, hence rank S is largely enough.
Whatever rank you buy for these, use the same ranking for the PNP/NPN
As I happen to have a curve tracer, I match al 4 of them within 10%

As for the WIMA caps: there should be a law and prison sentence against using those in vintage Japanese gear.
That's one of the worst things to do, turning heritage gear into a real DIY job.
Get some Xicon MPP.
Thanks, but everything is ordered and shipped unfortunately.
 
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