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Discussion Starter #1
Hi all,

I have the original Fender schem and wiring diagram but I can't seem to find the wiring diagram for the filter board in the doghouse. Would anyone know of a link to such a thing?

I am pretty sure I can put it together based on the schem and the many pictures I have of old Vibroverbs but I would reeeeally like to have the diagram.

Thanks in advance for any assistance.

Cheers.
 

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Its there in the schematic, but ever absent from the layout drawings. Be aware of the 2 series stacked caps with balancing resistors. This allows for twice the voltage ratings than 2 single caps in series.
 

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Discussion Starter #8
Its there in the schematic, but ever absent from the layout drawings. Be aware of the 2 series stacked caps with balancing resistors. This allows for twice the voltage ratings than 2 single caps in series.
Can I ask you to calrify something?

When you say, 'beware of the 2 series stacked caps', do you mean 'make note of' or discharge them working on the amp because they likely contain lethal voltages? Or perhaps I need to lock them up at nigh because they have been known to kill kittens and graffitti cars?
 

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Just a point of interest that I brought up...In some older amps, B+ caps were sometimes lined up all in parallel. As in my 1963 6G8 for example.
See here all + ends are in the same direction. Original, old and blistering. Each cap had a 550V rating. With today's modern voltages, and the amp on stand-by the caps can see
voltages higher than the rated 550 volts on the (first 2, leftmost cap location in photo). This nets 40 uF at 550V rating.



My hack layout version here:


However if we wire the first 2 caps in series as seen here, we net 40uF at 900V. Much better voltage protection. Note however I missed drawing in the balancing resistors on this layout, that are required.



I merely pointed out that your first two caps are wired in series. Just be sure to wire them back up that way. You probably knew this. I just like to remind folks.
Cheers. -K
 

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Discussion Starter #10
Wow! Thank you for the detailed response! That helps enormously.

I am still waiting on the caps for the doghouse bit i will likely start a build thread once all of the parts arrive.

Cheers.
 

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Discussion Starter #11
Oh, I should mention: This is a 'scratch build'. I plan to start a build thread once all of the parts have arrived (almost there).
 
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Discussion Starter #12
@keithb7 Slowly piecing this together. Here is a look at an original Vibroverb doghouse (old caps in all their splendour):

Photobucket
 
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