Derek92994's 700 Ser II White Oak conversion

[derek92994]

Very faint buzz from both channels, you have to put your ear right up to tweeter to hear. Right side a fraction louder. Pots right up, no input

 

[laatsch55]

Cool...

 

[derek92994]

How long should I idle it in spares before hooking up the pre again?

 

[Skratch]

I just got a set of 700 rev C backplane boards and there is no electrolytic capacitors all film caps, my revA 400 backplane had electrolytic caps

 

[derek92994]

I just got a set of 700 rev C backplane boards and there is no electrolytic capacitors all film caps, my revA 400 backplane had electrolytic caps

might be related to backplane revision.

 

[laatsch55]

How long should I idle it in spares before hooking up the pre again?

Give it a few hours Darc, then go with the 3600 and your spares , just idling for a few hours..

 

[laatsch55]

might be related to backplane revision.

It is. Joe fixed the Electro problem..

 

[Skratch]

might be related to backplane revision.

I think it is

 

[derek92994]

Give it a few hours Darc, then go with the 3600 and your spares , just idling for a few hours..

Will do, see how it goes and then later down the track we can put the 5 amp rail fuses back in. Very grateful for you and Joe’s help, also the members that have chipped in

 

[laatsch55]

Yep, that sounds like a plan...

 

[Gepetto]

Thank you for the replies. I shall get some rest and investigate further tomorrow. I welcome anymore advice on the repair path I should take. That backplane will have to come out to replace the capacitor and I do wonder how much life the other capacitors have on this and the other backplane. It may be wise to replace them all. Lets see what Lee and Joe think about this issue.

Those are not supposed to be in there Darcy. Taken out in a very early revision. More trouble than they are worth.

 

[Gepetto]

Do you think that capacitor was the problem from the start? Responsible for blowing the 2 outputs on those 2 separate occasions?

Did you remove all 4 electrolytic caps from the backplanes? You should.

 

[Gepetto]

It is. Joe fixed the Electro problem..

Yeah by taking them out of the artwork...

 

[derek92994]

Did you remove all 4 electrolytic caps from the backplanes? You should.

I shall power down and remove the rest, then will bring up on variac and dbt to be sure. Thank you Joe

 

[laatsch55]

Amen...

 

[laatsch55]

I shall power down and remove the rest, then will bring up on variac and dbt to be sure. Thank you Joe

NOW you can trim the leads close to the board...don't let em get away when ya trim em...

 

[Skratch]

I have 3 fully comp 400's with the revA backplane boards with electrolytic caps, they are 47uf 160 volt caps. Should they be removed?

 

[derek92994]

4 potential gremlins removed, just for shits and giggles

 

[derek92994]

Question, why is there no lead going from bus bar to centre connector on right backplane but the left backplane has?

 

[derek92994]

Oh, I see ground connectors going from 1 backplane to the other.