'68 100 watt board layout

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VelvetGeorge
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'68 100 watt board layout

Post by VelvetGeorge » Fri Aug 12, 2005 3:29 pm

Here's the standard '68 100 watt layout. Of course you will see variations and value differences.

The .68uf cap in parallel with the 820 in V2 shows up intermitantly.

The 330uf cap in V1 is often a 250uf.

George
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Post by VelvetGeorge » Fri Aug 12, 2005 3:31 pm

Here's a smaller preview.

George
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Post by NY Chief » Fri Aug 12, 2005 3:34 pm

How does this one sound as compared to the '67 layout? Sound clips soon, George?
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Guest

Post by Guest » Fri Aug 12, 2005 8:39 pm

This is the slightly later '68 version with the 2k7/0.68 split cathode arrangement. The earlier version has the 820/0.68 for the split on V1. Actually, from what I've seen "most" amps with the 2k7/0.68 cathode setup don't have the pre-amp filter cap on the tag board rather Marshall already made the switch to the six top mounted filter cap style by then.

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Post by Humbucker » Mon Aug 15, 2005 12:47 pm

Most of the '68 split cathode boards I've seen have 820 ohm/.68uf on V1b. Also, the V1 to V2 coupling cap from the bright channel should be .0022uf not .022uf.

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Post by VelvetGeorge » Thu Aug 18, 2005 8:29 pm

Here's an updated diagram with the alternate 820 in V1 and the .0022 listed.

George
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Post by Guest » Mon Aug 29, 2005 11:04 am

this seems pretty close to Ralle's board diagram. any chance you could post the diagram for the 69 SL board? im trying to work out which would be closest to Ralle's so I could buy the easiest one to mod, along with the necessary components at the same time.

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Post by rockstah » Mon Sep 26, 2005 6:31 pm

i know this maybe alot to ask but can some one point which of these on the 68 board are-

Electrolytic Capacitors

Coupling/signal Capacitors

Resistors

I would really apprceiate that :-)

Thames

Post by Thames » Tue Oct 04, 2005 3:35 pm

Cant see anything!

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Post by VelvetGeorge » Tue Oct 04, 2005 4:14 pm

They should be back up later today.

There may be 5 minutes of downtime while the change is made.


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Post by rockstah » Thu Oct 13, 2005 12:23 am

where is the 68 cap board layout?

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Post by tWreCK » Thu Oct 13, 2005 4:59 pm

There is no cap board on the later '68 amps - they're all on top

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Post by rockstah » Mon Oct 31, 2005 8:58 am

tWreCK wrote:There is no cap board on the later '68 amps - they're all on top
so a 68 build with one cap on top would be 2 100ufs and 2 32ufs as well as 16 or 32 on top?

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Post by Billy Batz » Mon Oct 31, 2005 9:06 am

They changed around a lot. That seems like th most common. But you could also see 4 100u caps and other value can on top as well as quite a few values for the preamp can. But my estimate (Im certainly no expert on marshall history) is the values you mentioned were most common.

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Post by rockstah » Mon Oct 31, 2005 9:20 am

Thanks Dan!

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