[sdiy] PCB size

[Veronica Merryfield]

David

My personal opinion would be to make one PCB. Mount the pots and rotary (if any) switches directly to the PCB. Use stand offs to hold it to the panel. The shaft holes are made a little bigger than the shafts and the knobs cover the gaps. You can mount the pots to the PCB by using a hole in the PCB to pass the pot through. If you pick the right switches (slide say), these can be PCB mounted as well and can poke through the panel. However, if you want to use panel switches, like the original, which all appear to be towards the bottom, set the PCB lower edge to be just above the switches. Mount the pcb then use short wires to the switches - you can bring the pads on the pcb to be in the right places for the switches.

I would also suspect that if you don't mind using links, you can probably do this as a single sided board. I would use a thicker board. If you don't want to use stand offs, use some aluminium angle along the edges or a bar along the middle with washers to hold it away from the board on the solder side unless you place components to allow it on the component side. Have the components away from the panel so you can get to them with the panel on. Make sure you mark the pot control names on component silk so you know what they are if you need to debug. 

You might not be able to find a PCB house to do a wide board but you could do it in 2+ sections. The biggest standard I have found so far in north america is 16" by 12" although I had a place in the UK that did 20" by 20" panels.

I'd also use a separate PSU pcb. The sockets in the rear could be wired.

But, like I said, this is my preference and not the only way to make it.

Veronica

On 2009-12-28, at 2:22 PM, David Ingebretsen wrote:

> I'm not quite sure how to explain my question...
> 
> I'm looking for opinions regarding making one bigger PCB versus several
> smaller PCB's for my Synthacon project.
> 
> I'm not so worried about cost difference, more about wiring and assembly
> efficiency.
> 
> Looking at the schematics and panel layout, it looks like there were several
> individual boards, VCO's on one, EG on another, etc. and flying wires were
> used to interconnect them. I want to keep the same basic look and feel of
> the original; single panel, no patch cords except to the keyboard, etc.
> 
> In some ways, it just seems so much simpler to make one large PCB and use
> PCB mounted switches, pots, etc where possible.
> 
> But, the complexity does increase and while cost isn't that big a factor, I
> can see the cost going way up because there would be a lot of blank space on
> the bigger PCB.
> 
> I guess I'd just appreciate any thoughts on the matter as I'm sure there are
> many of you who have done far more PCB designs than I have and much more
> complex ones that the Synthacon designs.
> 
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