B-2 for spare parts NOT V-Fets

rottalpha

Yamaholic
Subscriber
Does any one here have a defunct B-2 ???

I am looking for a working VU-meter, the right side if it makes a difference (if anyone knows if they are the same or indexed, please advise!)

I am also looking for the rear plate with the speaker posts.


I have purchased a B-2 with bad VU-meter and poorly altered inputs (RCA's) and speaker posts.
The meter does not work and may as well be something with the circuitry, but it also has a bent needle. At any rate, the vu meter will have to be replaced.

I am interested in ether of these parts, all the parts or the entire non-working B-2.

Any help or advise would be greatly appreciated.
 
Hello rottalpha

Vu meters on UC1, and B2 are identical .

Left and right are of course the same .

What parts do you need excactly ? A non working B2 is heavy .

Where are you ?

I never got a B2 with non working meter . Are you sure that this is not coming from the meter circuit ?
 
A bent needle (meter arm) sounds strange (unless something came through the front and smashed it), but if the coil and needle bearings are still intact, it is likely it can be repaired.
 
Does any one here have a defunct B-2 ???
I am looking for a working VU-meter, the right side if it makes a difference (if anyone knows if they are the same or indexed, please advise!)
I am also looking for the rear plate with the speaker posts.
I have purchased a B-2 with bad VU-meter and poorly altered inputs (RCA's) and speaker posts.
The meter does not work and may as well be something with the circuitry, but it also has a bent needle. At any rate, the vu meter will have to be replaced.
I am interested in ether of these parts, all the parts or the entire non-working B-2.
Any help or advise would be greatly appreciated.

I may be able to help you there.
The VU-meters are the same (left and right) and as far as I know the UC1 controller for the B1 also uses the same ones. I should have one spare.
I also do have a back panel but I think I don't have the speaker connector panel to go with it. This particular B2 was smashed by the UPS but also previously rather badly modified regarding input connectors, and I only have one pair of the originals.
I also have a few boards that came out of it, the VU-meter board and the aux power supply and protection board. Maybe also the rear connector board but without the cinch inputs. Let me have a look and I'll get back to you.
 
WOOW, thank you everyone for the quick response!

Patrice, I am in the States, constantly between SF and Chicago. Shipping the entire B-2 is probably not feasible. Shipping the individual parts may not be that bad. I will see if I can source them locally first.
I really appreciate your input. To answer your question, Yes the problem could may as well in the circuit..but have not yet taken the amp apart. The fact that the meter shows to have been tempered with, I would like to secure a replacement for it before I take the amp apart.

VintAge and John, that is what I was wondering too....I am assuming that someone tried to fix it somehow. The needle is bent as if it was bent once and then unsuccessfully straightened. I did not have time to take a closeup shot, but this coming weekend I will be able to get some extra photos and post them (I am out of town at the moment). I rather buy a "virgin" meter and then worry about the circuit board...or buy a "virgin" meter and working board...and not mingle too much with what seems to be a fairly complex circuit (for the meter board alone that is).

ilimzn, what is your location? I will take what you have. I would eventually need the speaker posts since this amp had a rather barbaric "upgrade" of the speaker posts and the RCA inputs. Which brings the reason why I actually need the rear plate. The rear input posts may have as well been installed by a car mechanic....and while tightening these posts, the paint of the rear cover around the posts got damaged.


So to make the story short; I picked this amp up on fleabay a couple of months back and did not have time to look in to fixing it yet. Here are some of the photos from the fleabay listing.

BTW, doesn't the needle of the right meter look to be thinner as well?
 

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Rottalpha,
I have checked and sadly my back plate is in a far worse condition than yours, in my case the metalwork was cut up (really badly) around the binding posts, which is why I did not remember the binding posts being there. In any case i would recomend an upgrade, but properly done. I normally use a piece of plexiglass cut to measure and drilled to carry the new binding posts using the original mounting holes.
What i do have is the following:
1) 1 working VU meter (the other suffered a fate similar to yours - the needle is bent, I still have it though)
2) 1 complete aux power supply and protection board
3) 1 complete VU meter drive board
4) 1 bulb carrier board
5) 1 input connector board but without the original binding posts (the caps, switches and resistors are all there)
6) 1 original stereo binding post for the above board (the one normally used for external VU meter input)
7) A few odds and ends like the bulb board bracket, but I assume these would just increase the shipping cost.
I am in Croatia, so shipping might be expensive. Need to weigh the parts and try to find out exactly how much.
Both boards should be working as they were pulled off a working B2 with aforementioned and other cosmetic problems (such as a completely destroyed front panel :( ).
 
ilimzn,

Croatia is a bit far...further than Patrice's location. I will keep on searching locally.

Thanks,

Peter
 
If you decide that you could use a whole B-2 (with bad left channel VFET outputs), then shoot me a PM. I'm about 3 to 4 hours south of Chicago.
 
Are you suggesting that you have (or know where to obtain) four good VFET output transistors that are properly matched?

yesshows77, read through Clinic's posts.....he may be on to something.

As far as your amp goes, I would almost feel bad to take it apart just for one vu-meter..If there is a chance that Patrice can help you fix it...I would be the first to cheer :banana: One other B-2 brought back to life is always a good thing.
As far as my amp goes, not to worry. I am sure that I would be able to find the vu-meter from a different source.
 
Hi guys, this weekend I was planing to take the amp apart so that I can swap the working meter with the non working meter to determine if the meter circuit is also compromised.

Anything I should watch for?
Is this a horrible idea that is going to somehow fry the v-fets and blow the house up or something like that...
Critics, please go at it first..I need to know what the worst possible scenario would be.

I decided not to hunt for the back plate or the original speaker posts. All I will need is the meter or the meter and the meter board....unless I find other surprise when I open the amp (hope not).
 
yesshows77, read through Clinic's posts.....he may be on to something.

As far as your amp goes, I would almost feel bad to take it apart just for one vu-meter..If there is a chance that Patrice can help you fix it...I would be the first to cheer :banana: One other B-2 brought back to life is always a good thing.
As far as my amp goes, not to worry. I am sure that I would be able to find the vu-meter from a different source.


I did a search on Clinic's posts and was not able to find anything specific regarding replacing the VFET outputs on a B-2, so if you know of such a post, please PM me the link. All four VFETs are indeed bad on on channel, as verified by a Yamaha certified service shop and Echowars.
 
I did a search on Clinic's posts and was not able to find anything specific regarding replacing the VFET outputs on a B-2, so if you know of such a post, please PM me the link. All four VFETs are indeed bad on on channel, as verified by a Yamaha certified service shop and Echowars.

If Ecowars said the left channel v-fets are gonne then they are gonne

Clinic will respond if he can help you. He really knows these amps well and he is one of the guys with a magic hat when it comes to some unobtanium components, but I have no idea if him or anyone else could source the v-fets for your left channel. I did not mean to give you the wrong idea...sorry if I did.
What I was referring to are posts such as this one at #27, albeit, he is talking about different amp /preamp unobtanium components ...(http://mail.audiokarma.net/forums/showthread.php?t=526450&page=2)

Not sure what Clinic / Patrice can help you with, but if I were you, I would PM him and ask if he can service your amp.

What I would imagine that would be another possibility is to locate another damaged amp with one good channel, then send him the parts to put your amp together...

All I was really saying is that if he can help you save it, then I would be the first to cheer.
I do think that would be silly for me to take your amp just for one of the vu-meters. I am sure that I can find a meter from a more damaged or already dismantled amp.

Good Luck
-Peter
 
Hi guys, this weekend I was planing to take the amp apart so that I can swap the working meter with the non working meter to determine if the meter circuit is also compromised.

Anything I should watch for?
Is this a horrible idea that is going to somehow fry the v-fets and blow the house up or something like that...
Critics, please go at it first..I need to know what the worst possible scenario would be.

I decided not to hunt for the back plate or the original speaker posts. All I will need is the meter or the meter and the meter board....unless I find other surprise when I open the amp (hope not).

hello rottalpha

to make your test you don't need to "swap" the meters ! each meter is connected to the "meter board" by one RED and one white wire . Just desolder wires of the left meter and connect them to the right meter connection . Then do the same with the wires of the right meter . It will take you 30 second to do it and you will see if your damaged meter works or not :thmbsp:
 
Are you suggesting that you have (or know where to obtain) four good VFET output transistors that are properly matched?


yes, I do ;

I have also some YAMAHA B2 needed service , they are not in perfect condition but every damaged part is rebuilt or cleaned when it is rusty :banana:

see my chassis pictures !
 

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I forget to add the picture of my 4 VFET mounted on B2 heatsink last week

(they are new of course)

here is the last picture of a renewed B2 chassis :thmbsp:
 

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