Mr. Yamaha
Not so much Yamaha lately...
I have replaced all in my B-2 and C-4 because they have a high failure rate. But others will say that it's not necessary.
I have replaced all in my B-2 and C-4 because they have a high failure rate. But others will say that it's not necessary.
amr2
Well-Known Member
Yes, the problem seems to be that the Vf voltage is unstable and fluctuates, so I think It's better to change them.
I think I have almost everything I need
Are you sure?
Often Murphy's law applies to me....
"When N items are needed for a project, N-1 are available"
I like those Nippon-Chemicon U36D !
Where did you get them?
amr2
Well-Known Member
And to me!
Mouser. They are not very expensive. EPCOS cost twice as much
Mr. Yamaha
Not so much Yamaha lately...
Nice work! Gotta love that special Yamaha glue
clinic-audio
all on YAMAHA untill 1990
yes , the other , it is me
Not necessary at all and you probably don't know that MV12 is the perfect sub for VD1212 and I can tell you that after replacing these varistors by 2 diodes in serie will not change anything regarding your trouble of unstable voltages !
give us a report
a glass bid blaster would make things much easyer....
I bet it will look great. Do you have to do anything to the front and/or back plates?
amr2
Well-Known Member
I only want to change them because they are known to be a real troublemakers. My unit doesn't have any problem, but I want to avoid future problems... MV12 doesn't have those issues?
amr2
Well-Known Member
Oh yes, with a glass bid blaster is MUCH easier....
The front plate have some deep marks caused by the screws that fixed the amp in the rack. The back plate is fine. The heat sinks have some scratches, but they were easy to remove.
Mr. Yamaha
Not so much Yamaha lately...
You will never stop talking about the illusive MV12, will you?
clinic-audio
all on YAMAHA untill 1990
One guy decided one day to put on the web that 2 X 1N4148 = VD1212 and everybody repeat this "trick" without knowing what they do . 2 diodes in serie are not = to a varistor
YAMAHA is not the same manufacturer using VD1212 .SONY did it too .
If you take the SONY data sheet book to see data about VD1212 you will read that 2 X 1N4148 in serie are not the subtitute ! this true is not only regarding YAMAHA it is the same for all manufacturers ! if you choose to advise any AK member to replace all varistors (silly project) in their unit , this is your choice not mine and AK is not here to give wrong information .
I always give 100% sure informations and not something I have read on the web somewhere
If I asked to amr2 to send a report it is just to proove to you and other AK members reading this post, that this " trick" is not justified , and so not necessary to loose your time to replace parts for nothing .....
You said "illusive"
I don't work with the "help" of google
Google don't know the true . Google repeat pages without knowledge, not me .
If you are not able to find MV12 (original japanese sub recommendation ) this is not my problem .
Any official service station (worldwide) is able to spupply this part if you accept to pay the price . If you think you better know than anybody tell to all AK members . They will be happy to see that you share your source .
I bought all my parts from offical YAMAHA service agent and I don't have any trouble with fake components like you will when buying parts to web "sellers" , because chasing the best good deal .
You will never stop talking about the illusive MV12, will you ?
As soon that it is true that MV12 is the only and perfect sub for VD1212 , NO
YAMAHA is not the same manufacturer using VD1212 .SONY did it too .
If you take the SONY data sheet book to see data about VD1212 you will read that 2 X 1N4148 in serie are not the subtitute ! this true is not only regarding YAMAHA it is the same for all manufacturers ! if you choose to advise any AK member to replace all varistors (silly project) in their unit , this is your choice not mine and AK is not here to give wrong information .
I always give 100% sure informations and not something I have read on the web somewhere
If I asked to amr2 to send a report it is just to proove to you and other AK members reading this post, that this " trick" is not justified , and so not necessary to loose your time to replace parts for nothing .....
You said "illusive"
I don't work with the "help" of google
Google don't know the true . Google repeat pages without knowledge, not me .
If you are not able to find MV12 (original japanese sub recommendation ) this is not my problem .
Any official service station (worldwide) is able to spupply this part if you accept to pay the price . If you think you better know than anybody tell to all AK members . They will be happy to see that you share your source .
I bought all my parts from offical YAMAHA service agent and I don't have any trouble with fake components like you will when buying parts to web "sellers" , because chasing the best good deal .
You will never stop talking about the illusive MV12, will you ?
As soon that it is true that MV12 is the only and perfect sub for VD1212 , NO
amr2
Well-Known Member
I can get the MV12. Do you recommend replacing the VD1212 (that is working normally) with the MV12 to avoid future problems?
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clinic-audio
all on YAMAHA untill 1990
If you don't have any troubles , no .
I honestly don't think that you will have trouble in the future . Varistor can be dammaged by overheating and then specifications move . To preserve them of that, there is a sleeve (tube) around to act like a temperature shield . If your varistor is good today , I don't see any reason it will not good tomorow .
I honestly don't think that you will have trouble in the future . Varistor can be dammaged by overheating and then specifications move . To preserve them of that, there is a sleeve (tube) around to act like a temperature shield . If your varistor is good today , I don't see any reason it will not good tomorow .
