700B blew one Right channel 5A supply fuse

laatsch55

Administrator,
Staff member
Joined
Jan 14, 2011
Messages
74,987
Location
Gillette, Wyo.
Tagline
Halfbiass...Electron Herder and Backass Woof
K, Hole #12, negative(ground) ftom left channel signal in. Make sure only the negative wire and NO SHIELDING gets soldered here. The shielding is attached at the copper plate and that should be the only connection for it.
 

62vauxhall

Veteran and General Yakker
Joined
May 14, 2014
Messages
2,324
Location
Southwest Kootenays BC
Tagline
No such things as bad days, just bad moments
K, Hole #12, negative(ground) ftom left channel signal in. Make sure only the negative wire and NO SHIELDING gets soldered here. The shielding is attached at the copper plate and that should be the only connection for it.
Need some clarification again. Isn't it the shield that's the negative (ground) from left channel signal in and it's the centre conductor that connects to the board?

And, that signal in lead actually comes from the volume pot?
 

laatsch55

Administrator,
Staff member
Joined
Jan 14, 2011
Messages
74,987
Location
Gillette, Wyo.
Tagline
Halfbiass...Electron Herder and Backass Woof
I may have screwed you up on this earlier come to think of it.....At the copper plate the signal ground and the shield should be soldered together on the copper plate. And only the ground wire to the board. Take a pic of the pots right quick...
 

laatsch55

Administrator,
Staff member
Joined
Jan 14, 2011
Messages
74,987
Location
Gillette, Wyo.
Tagline
Halfbiass...Electron Herder and Backass Woof
Scrath that. That's hpow we do the White oak board. The shield should be on the board in said #12 hole, signal positive in hole #13...
 

62vauxhall

Veteran and General Yakker
Joined
May 14, 2014
Messages
2,324
Location
Southwest Kootenays BC
Tagline
No such things as bad days, just bad moments
I may have screwed you up on this earlier come to think of it.....At the copper plate the signal ground and the shield should be soldered together on the copper plate. And only the ground wire to the board. Take a pic of the pots right quick...
Both shield leads are connected to the copper plate.

Left channel signal pot.

IMG_2098.jpg

Right channel pot.

IMG_2097.jpg
 

62vauxhall

Veteran and General Yakker
Joined
May 14, 2014
Messages
2,324
Location
Southwest Kootenays BC
Tagline
No such things as bad days, just bad moments
Scrath that. That's hpow we do the White oak board. The shield should be on the board in said #12 hole, signal positive in hole #13...
Done and sorry for the delay. These connections took longer to make. Needed to improvise due to the large amount of shield material.
 

laatsch55

Administrator,
Staff member
Joined
Jan 14, 2011
Messages
74,987
Location
Gillette, Wyo.
Tagline
Halfbiass...Electron Herder and Backass Woof
Ok, I have to get up early tomorrow Gary. On the right channel side of the board starting on the left, #1 is red, unfused B+ to the positive terminal of the power supply upper cap.

I'll run through the rest in the next post...
 

62vauxhall

Veteran and General Yakker
Joined
May 14, 2014
Messages
2,324
Location
Southwest Kootenays BC
Tagline
No such things as bad days, just bad moments
Ok, I have to get up early tomorrow Gary. On the right channel side of the board starting on the left, #1 is red, unfused B+ to the positive terminal of the power supply upper cap.

I'll run through the rest in the next post...
Done, but i have to drop this for now too.

I live in a condo building and an elderly neighbour lady apparently returned yesterday from a few days in the hospital. She is very confused and wandering the hall, trying to let herself in to different suites including mine.

I've got one of the strata council members with me and the two of us, will stay with her until son/daughter or someone can be contacted.

Can't let her be alone right now, I'm sure she's very scared.

Will post again in the morning,
 

laatsch55

Administrator,
Staff member
Joined
Jan 14, 2011
Messages
74,987
Location
Gillette, Wyo.
Tagline
Halfbiass...Electron Herder and Backass Woof
#2---white/ green/black stripe....collector bus bar positive drive right channel..

#3----red, collector, bias transistor, Q6 right channelk..

#4---blue, base of Q11, right channel

#5---Black, base of bias transistor, Q6 right channel

#6----Brown, emitter Q13

#7, orange, collector bus bar, positive drive right channel

#8---Grey, collector Q12, negative drive, right channel

#9---White, chassis ground, middle of right 3 terminal strip..

#10---yellow, collector of Q14

#11----brown, emitter of bias transistor Q6, right

#12----Purple, base of Q12, negative drive, right channel

#13---signal ground, right

#14 signal positive , right...

We'll power up tomorrow if ya think it's ready...
 

laatsch55

Administrator,
Staff member
Joined
Jan 14, 2011
Messages
74,987
Location
Gillette, Wyo.
Tagline
Halfbiass...Electron Herder and Backass Woof
Done, but i have to drop this for now too.

I live in a condo building and an elderly neighbour lady apparently returned yesterday from a few days in the hospital. She is very confused and wandering the hall, trying to let herself in to different suites including mine.

I've got one of the strata council members with me and the two of us, will stay with her until son/daughter or someone can be contacted.

Can't let her be alone right now, I'm sure she's very scared.

Will post again in the morning,

You're a good man Gary, help the poor woman...
 

62vauxhall

Veteran and General Yakker
Joined
May 14, 2014
Messages
2,324
Location
Southwest Kootenays BC
Tagline
No such things as bad days, just bad moments
#2---white/ green/black stripe....collector bus bar positive drive right channel..

#3----red, collector, bias transistor, Q6 right channelk..

#4---blue, base of Q11, right channel

#5---Black, base of bias transistor, Q6 right channel

#6----Brown, emitter Q13

#7, orange, collector bus bar, positive drive right channel

#8---Grey, collector Q12, negative drive, right channel

#9---White, chassis ground, middle of right 3 terminal strip..

#10---yellow, collector of Q14

#11----brown, emitter of bias transistor Q6, right

#12----Purple, base of Q12, negative drive, right channel

#13---signal ground, right

#14 signal positive , right...

We'll power up tomorrow if ya think it's ready...
Up to and including #8 is done.

I stopped because for #9, the white chassis ground wire in this amp does not go to the centre lug of the right 3 terminal strip. It goes instead to the negative left speaker terminal. That terminal was connected to the copper plate by that thick wire which I snipped off as directed.

I can certainly remove the white wire from the negative speaker terminal and solder it to that centre lug but thought I'd wait for your say so.

In other words, neither that white wire or the negative speaker terminals are now connected to chassis ground.
 

laatsch55

Administrator,
Staff member
Joined
Jan 14, 2011
Messages
74,987
Location
Gillette, Wyo.
Tagline
Halfbiass...Electron Herder and Backass Woof
Well, being you have to relocate it , take it to the star ground point between the big caps.
 

62vauxhall

Veteran and General Yakker
Joined
May 14, 2014
Messages
2,324
Location
Southwest Kootenays BC
Tagline
No such things as bad days, just bad moments
Sorry again for the dalay. I was not happy with the connection of the signal leads to the Normal/Direct switch so tore it apart and re-did it. Also had to dig out the gun to get the solder on the star ground bus bar to flow.

All wires are now connected to the board. Should I be optimistic and bolt it back in place?

In about an hour I have to leave for while. I told a cousin I would help her move stuff from her basement. Will be back about 4PM or 5PM for you.
 

laatsch55

Administrator,
Staff member
Joined
Jan 14, 2011
Messages
74,987
Location
Gillette, Wyo.
Tagline
Halfbiass...Electron Herder and Backass Woof
Still in the field. Yeah, I want to be there for the power up. Leave the board where it is for now.
 
Top