[hpsdr] Mercury

[Philip Covington]

On 9/24/06, Lyle Johnson <kk7p at wavecable.com> wrote:
> Hello Phil!
>
> > To do what we want we would need a larger FPGA, yes.  The larger FPGA
> > and configuration device exceeds the cost of using the AD6636.
> >
> > Unless we are going to build everything out of 2N2222s then we are
> > always going to have the problem of chips becoming obsolete.  I doubt
> > the AD6636 is going to become obsolete too soon.  What about the ADC?
>
> How about 2N404s?  :-)
>
> > I am not afraid of BGAs.
>
> Nor am I, I just want to avoid them :-)
>
> But clearly for this product we can't.
>
> We do need a way to put down BGAs for prototyping.  I'm trying to talk
> AMSAT into getting a BGA placer-downer (techno speak, I know) to support
> this kind of activity.  It would mean the volunteer with the BGA tool
> would have to agree to place BGAs for a reasonable number of prototypes
> for the HPSDR and AMSAT projects.  Meanwhile, we can pay $200 or so per
> BGA to have them placed until we get such a machine.

Here at work we are looking at a Zephyrtronics system.  At least I
hope the department head approves it.  Otherwise I will continue
placing them using the oven.

> So, since we're going to have the AD6636 on here anyway, why not put a
> larger-capacity FPGA on as well and not worry if it is also BGA or not?
>
> Lyle

Certainly we could and maybe should, but the cost of the larger FPGA
and configuration device is going to push the cost of the whole board
even higher.  We don't need the IO for the Mercury, we need the LEs.
I guess maybe that shouldn't be a worry since it will be an expensive
board anyhow.

73 de phil N8VB

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