Yamaha C4 - zener diode WZ130 - Power C Board

[avionic]

They are all be identified on the schematic diagram.

 

[Hifibythekg]

Thanks Dave.
Seems like I’m all sorted for replacing all the diodes on the board.
If.. I should need to replace any VD1212, can I use this, below, by joining them in series?
https://uk.farnell.com/on-semiconductor/1n4148ta/diode-ultrafast-300ma-100v-do/dp/2322485

 

[avionic]

Yes

 

[Hifibythekg]

Thanks.
Tempted to try replacing the 2SK100 with a matched pair of LSK170’s.
‘LSK170 Quad 6-8mA‘ from DIYAudio.
Is there something off the shelf that can thermally couple two transistors? Like a small open copper tube.., if so what’s it called and who sells ‘em?

 

[Nashou66]

Thanks.
Tempted to try replacing the 2SK100 with a matched pair of LSK170’s.
‘LSK170 Quad 6-8mA‘ from DIYAudio.
Is there something off the shelf that can thermally couple two transistors? Like a small open copper tube.., if so what’s it called and who sells ‘em?

Why? Did you measure them to see if they are not well matched?
The sk100's are an inline chip trying to get the sk170's to " meet each other face to face will prove extremely challenging.

For differential pairs many use heat shrink tubing with the faces of the two transistors touching with thermal paste between them for coupling them thermally .

Athanasios

 

[Hifibythekg]

Thanks Nashou.
I had one faulty 2sk100 in the C4, borrowed one from the A1. Could hear the difference on each channel.
This component has an audible affect on sound character.

 

[Hifibythekg]

Hi guys, on the Flat Amp board at location C313 there’s a ‘Luxon’ 33uF 35V cap which I’ve read (@avionic ?) can be replaced with a 33uF 16V Nichicon PW. I can’t readily obtain this cap but do have 33uF 35V caps in either:

-Panasonic FC

-Panasonic EEUHD

Which, if either, of these would work best?

 

[Hyperion]

I would use the Panasonic FC, the other one is very ordinary and not as good as the FC.

 

[Hifibythekg]

Thanks @Hyperion, much appreciated.

 

[Hifibythekg]

Oops, correction.
My choice is a Panasonic FM or FC in this location.
Any preference?

 

[avionic]

Any preference?

Serviceable would be KEY

 

[Hifibythekg]

Serviceable would be KEY

Thanks Dave, I’m probably missing the obvious, but what do you mean? That the component should be able to provide a lot of service?

 

[avionic]

Serviceable versus non-serviceable.. Good verses bad.

 

[avionic]

The 33µf@16vdc is a low impedance cap.( Z ) ie . Nichicon UPW or similar.
Either Panasonic FC or FM will do.. This cap is in the mute relay timing delay circuit. No audio path..

 

[Hifibythekg]

Fantastic.
Nice to be advised and educated simultaneously.
As it happens, I put the FM in.