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Hoffman Amps Forum image Author Topic: Dumble PCB boards project  (Read 10431 times)

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Offline frusciante89

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Dumble PCB boards project
« on: December 28, 2019, 04:09:57 pm »
Hi everyone!
Me and my friend/colleague from the ampgarage are creating a universal PCB board for Dumble clones: it will contain all the components in one single board, 2 oz Cu copper density, 3 mm traces, and 3 mm thick board (no need to use three separate boards and two auxiliary boards for the relays - it will be all together). This comes after years of building Dumble clones the old way, and from the pain of having three separate PCB boards  :sad2:
These are a couple of layouts drawn using our boards:


.

.

.

Any suggestion/addition to the board is appreciated.. we'll send the project to the PCB manufacturer early Jan, so we still have some time for minor tweaks :)
If anyone is interested let me know. PM me if you would like one (or ten :icon_biggrin: )
Cheers from London!

Offline DummyLoad

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Re: Dumble PCB boards project
« Reply #1 on: December 28, 2019, 09:02:18 pm »
where are the mount points?


--pete

Offline EL34

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Re: Dumble PCB boards project
« Reply #2 on: December 29, 2019, 07:42:16 am »
The drawings look nice
I would still do them as eyelet boards though

Just my preference   :icon_biggrin:
« Last Edit: December 29, 2019, 03:56:15 pm by EL34 »

Offline kagliostro

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Re: Dumble PCB boards project
« Reply #3 on: December 29, 2019, 11:51:41 am »
Quote
I would still do them as eyelet boards though

Or, at least PCB + Turrets, like in some VOX amp



or other cool constructions  :icon_biggrin:



Franco
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Offline SILVERGUN

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Re: Dumble PCB boards project
« Reply #4 on: December 29, 2019, 02:36:06 pm »
Hi everyone!
Thank you for sharing, these look pretty cool.
If I needed to do a quick D style build I would definitely consider.
What is the projected overall length?

Offline frusciante89

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Re: Dumble PCB boards project
« Reply #5 on: January 02, 2020, 12:35:09 pm »
where are the mount points?


--pete
Hi pete! You can find them in the picture attached. They're metric M3 sized.

Offline frusciante89

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Re: Dumble PCB boards project
« Reply #6 on: January 02, 2020, 12:39:41 pm »
And this is the board with the traces. Each traces is at least 2 mm thick, apart from the relay section that has 1.75mm thick traces (more than enough)

Offline SILVERGUN

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Re: Dumble PCB boards project
« Reply #7 on: January 08, 2020, 08:30:17 pm »
PM sent last week, no response

Offline frusciante89

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Re: Dumble PCB boards project
« Reply #8 on: May 02, 2020, 12:22:15 pm »
Hi guys! THE DUMBLE BOARDS HAVE ARRIVED!!!  :D
the manufacturing took way longer than expected because of the lockdown, but I think it was worth the wait!
The boards look AMAZING: I'm attaching some pictures below. For anyone interested, please email me at ggfabianni @ gmail.com, I can start shipping them to you as early as next week! Batch quantity is limited (had only 20 made due to the scarcity of the 3mm FR4 material), so first come, first serve  :D email your address so we can sort out shipping fees.
Final dimensions are 34.5 x 11.5 cm.

From the pictures you should appreciate the quality of the tinning and the thickness of the traces, especially in the power section. Also, to ease mounting and limit mistakes, I've indicated all of the wires coming and going from the board. On top of that, there are passthrough holes for those wires, to improve dressing and keep the build as tidy as possible (I'm a bit OCD on the details).
All the connections are detailed in the layouts I've posted some pages ago, and you can build ANY Dumble model with this board (I'm attaching an example of the layouts for the #102 model). Due to the small batch and the engineering charge for these small projects, one board is £50! Also, these are not the normal 1.2mm, but 3mm thick... in addition, it's 2oz/m^2 copper density, compared to the standard 1oz/m^2. They're basically bullet proof  :D









« Last Edit: May 02, 2020, 12:26:06 pm by frusciante89 »

Offline frusciante89

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Re: Dumble PCB boards project
« Reply #9 on: May 06, 2020, 06:34:02 am »
My #102 is coming to life!  :icon_biggrin:


Offline kagliostro

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Re: Dumble PCB boards project
« Reply #10 on: May 06, 2020, 09:10:12 am »
Are the holes on the PCB larges enough to permit to use turrets on it ?


Franco
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Offline Madkrafter

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Re: Dumble PCB boards project
« Reply #11 on: July 27, 2020, 02:33:45 pm »
I just talked to my buddy who helped me with my AB763 build about building a Dumble 102 (Robben Ford) last night. Are any of these still available?

Offline SILVERGUN

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Re: Dumble PCB boards project
« Reply #12 on: July 27, 2020, 02:36:00 pm »
Try to reach him at his email which is in Reply #8

Offline Madkrafter

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Re: Dumble PCB boards project
« Reply #13 on: July 28, 2020, 09:21:07 am »
I did. Just thought that I would double up and post here too.

Offline sluckey

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Re: Dumble PCB boards project
« Reply #14 on: July 28, 2020, 09:34:55 am »
He's more active over at the amp garage.
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline DummyLoad

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Re: Dumble PCB boards project
« Reply #15 on: July 28, 2020, 12:04:59 pm »

Offline Madkrafter

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Re: Dumble PCB boards project
« Reply #16 on: July 28, 2020, 11:14:52 pm »
Thanks sluckey and Dummyload. I think I've changed my mind and would much rather do an eyelet board.

Offline frusciante89

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Re: Dumble PCB boards project
« Reply #17 on: November 04, 2020, 09:53:07 am »
Hey Madkrafter, the boards doesn't allow turrets

Offline smilch

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Re: Dumble PCB boards project
« Reply #18 on: November 12, 2022, 08:46:04 am »
hello to anyone out there I just purchased one of these boards and I was wondering where you got the chasis from . I am having a hard time finding a pre drilled one

Scott.

Offline sluckey

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Re: Dumble PCB boards project
« Reply #19 on: November 12, 2022, 08:52:07 am »
hello to anyone out there I just purchased one of these boards and I was wondering where you got the chasis from . I am having a hard time finding a pre drilled one

Scott.
You  can probably find a chassis at The Amp Garage.
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline acheld

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Re: Dumble PCB boards project
« Reply #20 on: November 12, 2022, 09:56:29 am »
Quote
I was wondering where you got the chasis from . I am having a hard time finding a pre drilled one

I built one of these in the past.  The board quality is excellent, but you really have to pay attention to the schematic with regard to options you have.

This is a complex build, despite the PCB.  The PCB is large, and there are lots of components off the board.

My recommendation is that you plan your build carefully, laying out your components and seeing what kind of space you need --- and then order a custom chassis (undrilled or drilled according to your specs). 

Planning is key here.  The amp sounds good, but I had to deal with some noise issues -- and that, of course, is part of HAD's craft that his amps were quiet, yet high gain.

Sluckey is correct about TAG. That is where most of these builders hang out, it seems.

 


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