[sdiy] PCB size for euro-rack format

[Seb Francis]

Laurie Biddulph wrote:
>
> So, 2 holes for mounting will be fine. Remember that mounting the 
> board on to the bracket will require some horizontal height (unless 
> you are providing a clear area on the pcb where the bracket would be 
> mounted) and this has to be factored in to the panel width. So, for 
> example, if mounting the board behind a column of jacks or toggle 
> switches, you will probably find that the pcb will be sitting 
> somewhere central to that column and so you may have to consider any 
> tall components such as electrolytics and where they will be extending 
> in to.
>
> This bracket approach was used on the ETI 4600, Maplin 3800/5600 
> synths. In there case, the pcb had a whole side left blank so that the 
> pcb could be mounted directly on to the bracket. This results in the 
> pcb sitting to one side of the column of components based on the 
> dimension of the bracket. This is quite wasteful in pcb real estate so 
> you may need to consider just defining a small area around the 2 
> fixing points to allow for a small spacer to be inserted between the 
> pcb and bracket. This will maximum the available pcb space for 
> circuitry but reduce the maximum height of components by the height of 
> the spacer. Given that a good thru-hole solder connection should be 
> between 1mm and 2mm below the pcb, you will need to be looking at a 
> minimum of a 3, probably, 4mm spacer.
>

There's actually no thru-hole components at all on the edge where the 2 
mounting holes are, so a bracket could fit flush to the PCB.

But anyway in the case of this module I think the panel is always going 
to be on the wide side as there is much possible I/O (up to 12 CV pots 
and/or CV inputs, up to 8 Gate inputs and/or buttons, up to 10 switches, 
MIDI, ICSP ... you get the idea!)

My current draft control specification is:
http://burnit.co.uk/sdiy/stuff/Digi-Mod-Controls.html

'CV' means CV pot and/or CV input
'Gate' means a button and/or gate input
'Switch' means a toggle switch
'2-bit rotary' means a 4 position rotary switch


Seb