[hpsdr] [ATLAS] Gerbers posted...

[Philip Covington]

On 3/10/06, vk4str <vk4str at netspace.net.au> wrote:
> I forgot to mention in my previous mail that the ATX PS connector needs
> special attention, in particular to the inner layer pads. The pads
> should be layed out as thermal pads type (that is a pad with a cross
> through it that connects to surrounding copper), so the  copper cannot
> draw all the heat away during soldering. This could also be problematic
> on the DIN41612 connectors, so a 'strong' soldering iron is required to
> produce a reliable solder joint.

Yep, I am aware of what thermals are.

I would agree with you on the ATX connector and DIN41612s if we never
intended to build a radio with the Atlas board.  I think it is more
important in this case to have as much uninterrupted ground plane as
possible on the top of the board.  There are so many ground pins on
the DIN41612s that thermals subtract a significant amount of the
ground plane right where we need it.  Remember, also, that the
DIN41612s will be soldered on the bottom layer which is a whole lot
easier than trying to solder on the top ground plane side with no
thermals.  For components that have to be soldered on the top side,
you will see that there are thermals.

I have no problem getting good solder joints on DIN41612s or MOLEX
type connectors with the same soldering iron I use for SMT.  A little
more flux than normal is needed when you have no thermals, but no
special "high power" soldering iron is needed.

If someone makes a convincing argument in the next two days about why
we absolutely need thermals on the pads you mentioned I will add them.
 Otherwise, I would like to keep the top ground plane layer as intact
as possible, especially in the area of the bus signals.

> I'm aware that my postings have been mainly critical in the past, but
> they should be seen as a positive contribution and not as personal
> nit-picking. I apologize for any ill-feelings in advance, just trying to
> contribute something useful at this stage.
>
> 73, Helmut

73 de Phil N8VB

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