Need clarification with capacitors on Grappler Minus Card

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Need clarification with capacitors on Grappler Minus Card

Hello fellow members,

A friend gave me a bare Grappler Minus board to build. I only found one BOM on the Github page.  I'm not sure if my revision corrosponds with this BOM but several capacitor values listed in this BOM don't match the silkscreening. The capacitors in question are C4 and C6.  The board has no silscreening for C7 at all and the BOM doesn't even list a C8. Can someone clarify the correct values at these locations for me so I'm not guessing. I didn't see an "issues" tab on the Github page or I would have asked directly. Hopefully someone has successfully built this revision and can clear this up for me.

Thanks.

 

 

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Joined: Apr 26 2016 - 08:36
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I built a few of these.I

I built a few of these.

I followed the silkscreen and the card worked with both a 2732 and a 2764.

 

Careful if you intend to use this with a Floppy Emu.  You will need to isolate pin 12 otherwise you'll fry the Emu.

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Last seen: 1 month 1 week ago
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Thanks. I'll follow the

Thanks. I'll follow the silkscreening on the card. Now, remember C7 doesn't have a value silkscreened.  Should I use the value from the BOM I listed?  100pf? C7 would be the only one in question now.

Thanks

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Last seen: 1 hour 16 min ago
Joined: Apr 26 2016 - 08:36
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Your card is v1.4, which

Your card is v1.4, which fixes some timing issues related to the WDrive.

With my version, v1.3, that capacitor doesn't exist, but according to this blog, the value of C7 is indeed 100pF

https://ameblo.jp/keroxiee1016/entry-12838344596.html

 

There are clearly some details missed in the published gerbers if this is the result.

 

 

 

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Last seen: 1 month 18 hours ago
Joined: Nov 19 2023 - 15:28
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Hello, This is a version I

Hello, 

This is a version I have done and that is working 

Hope it helps

V

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