Custom calypso board

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Harald Welte laforge at
Wed Jul 11 10:21:47 UTC 2012

Hi Mathias,

On Wed, Jul 11, 2012 at 11:39:21AM +0200, Mathias K. wrote:
> On 11.07.2012 10:26, Harald Welte wrote:
> >the core modem design is 40 x 29.8mm in size, but that of course
> >excludes things like the sim card reader, or any other new components we
> >may add.
> So it looks like the MiniPCI Express Card on this picture
> ?

I was thinking of a full-size PCIe connector like in desktop PC use.
This allows the modems to be 90degree angle from the main board.  The
miniPCIe or miniPCI connectors require the modem to be flat on top of
the base board, reducing the density and increasing PCB size of that

> > There are some signs that the supply of Motola C1xx phones is not
> > endless, after all.
> And this include the cases as well.

no, not neccessarily.  the cases are still being manufactured for spare
part / re-work.

> >undoubful great connectors, but I really wanted to keep it low cost,
> >thus the proposalf of using PCIe connectors on the backplane.  Needs no
> >connector on the board itself, just a bit of board footprint.
> Yes but that's only simple on one site and the board price increase
> because the extra milling ways but maybe for a 6 plane pcb it's not
> that much.

I think the 6-layer PCB will be espensive anyway, the milling of the
connector is probably not a big impact, as you indicated.

> I think the initial hurdle to get it run on the table is really high
> with this kind of connector.

Well, we can always make a simple PCIe break-out board that you can plug
the modem into.  That break-out could then provide you with a 2.54mm
pitch standard header.  Would that work?

> How a developer or backplane board should looks like and whats the
> estimated price relative to the modem price?

There's no thought about that so far, first we want to get the modem

- Harald Welte <laforge at> 
"Privacy in residential applications is a desirable marketing option."
                                                  (ETSI EN 300 175-7 Ch. A6)

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