[hpsdr] Some thoughts on plug-in board layout

[Philip Covington]

Please ignore the link at the very bottom.  I am in the process of
changing domain registrars so my website is not available right now.

Instead use:

<http://hpsdr.gotdns.org/> for the REVXA.5 PDF

73 de Phil N8VB



On 5/25/06, Philip Covington <p.covington at gmail.com> wrote:
> Hi Group,
>
> Current Form Factor:
>
> The current plan is a 100x100mm plug-in board format with a 96 pin
> DIN41612 on the bottom side and  the board specific external
> connectors on the top side.  It is loosely based on the Eurocard
> format.  There is the option of increasing the length of the card
> beyond 100mm, for example it could be 100x160, 100x200, etc...  The
> external connector area does not increase when we go to these longer
> boards.  There is a pretty good reason to no put connectors on the
> perpendicular (left and right) sides of the board:  If we allow longer
> boards than 100mm we will have to provide for board guides on those
> sides.  I put some longer (100x160 and 100x220) eurocard format boards
> that I had at work into the ATLAS.  With external connections those
> boards can put a lot of stress on the ATLAS connectors.  If we allow
> different board lengths it will make it very hard on those trying to
> use an ATX case for an enclosure.
>
> Proposed Form Factor (Alex):
>
> I am not sure we would have to stick with one board size here.  I
> looked at the ATX spec as well as the PCI card spec to determine the
> maximum board dimensions we could use.  It appears that we could allow
> 100x120mm, 100x160mm, 100x185mm (Alex's proposal), and 100x220mm.
> With 100x220mm we would be just inside the ATX motherboard footprint
> so we could use ATX cases for all sizes from 120 to 220mm length.  The
> longer boards in this configuration do not put as much stress on the
> ATLAS.  The DIN41612 takes up a good amount of the fixed 100 mm
> dimension.  There isn't this problem with PCI cards since they use
> gold fingers.
>
> Here is a PDF drawing of the proposed form factor:
>
> <http://www.hamsdr.com/personaldirectory.aspx?id=261>
>
> I added some the possibilities of the longer cards besides the
> proposed 100x185mm.
>
> I see pluses and minuses to each form factor.  I don't have any
> problem changing it or redoing the OZY layout (since it isn't too far
> along).  Lyle is further along on JANUS and he makes some good points
> about signal flow in a previous post.  It matters less with the OZY
> board since it is pretty much all digital signals (other than the USB)
> and there are not the concerns of separating the analog and digital
> sections like there is in the JANUS.
>
> Take a look at the drawing about and please comment.  We need to get
> this resolved soon so we proceed with the JANUS and OZY.
>
> 73 de Phil N8VB
>
> P.S.  Please take a close look at the OZY schematic REVXA.5.  If it
> looks good it will be the basis of the OZY alpha.  Very few made
> comments but I posted it right before Dayton.
>
> <http://www.philcovington.com/HPSDR/OZY/REVXA.5/>
>

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