FreeCalypso status update

Mychaela Falconia mychaela.falconia at
Tue Sep 4 00:28:54 UTC 2018

Hi DS!

> Just to understand a bit better the costs of fabrication of V2:
> does the PCB fabrication include the pick and place of the various
> components, or is it just the raw PCB?

The PCB fabrication cost which is expected to be somewhere in the $2600
to $3000 USD range is just the bare PCB panels.  We need to use the
same PCB fab ( that was used for FCDEV3B V1 (the precise
stackup and choice of specific dielectric materials matters a lot, we
went through a lot of work to settle on a good stackup in the previous
round that produced perfect RF tract performance on our V1 boards, and
I am NOT willing to disrupt all that delicate balance just because
someone else who is not in my shoes thinks another fab would be
cheaper), and I am also keeping the same panelization structure: 4
boards per panel.  If I am going to be paying for it on my own (in
however many more months it will take before I can afford it), I will
be ordering 5 panels this time, enough to make 20 boards, for me to
subsequently sell or give away in the subsidy program as I see fit.

> If so, what is the added cost
> of the components plus soldering them on each board?

The cost of components is not a factor because I have already bought
all of the necessary parts (enough for 20 boards), they have already
been paid for two months ago, and the physical parts are right here
in my hands at FreeCalypso HQ.

The final required step will be assembly; it is the step in which all
of the components are populated and soldered onto the PCBs in a highly
automated manner.  It has to be done in a highly automated manner,
using a laser-cut solder stencil and a pick-and-place machine because
the components are far too small and fine-pitched to be placed by
hand.  Anyone who claims to be able to solder 0.5 mm pitch micro-BGAs
by hand is deluding themselves.  I have an established working
relationship with Technotronix, an assembly shop here in Southern
California, and I will NOT entrust this job to anyone else.

The assembly at Technotronix is done on the granularity of panels, not
individual boards: a panel that will eventually yield 4 boards is
subjected to solder paste depositing (the laser-cut solder stencil
covers a 4-up panel, not a single board), populated with components
via the pick-and-place machine, and passed through the reflow oven
before being split into individual boards.  They do both visual and
X-ray inspection to make sure that their assembly is correct.

Because the pick-and-place machine has to be programmed specifically
for our boards and the production line has to be tied up for the
duration of our assembly run, doing larger quantities at a time is
always appreciated.  Doing just one panel at a time raises the cost,
thus I strive to do at least two panels at a time (yielding 8 boards)
whenever possible.  I plan on ordering 5 panels from the PCB fab and
then doing two assembly runs at Technotronix: first a run of two
panels, then the remaining 3.  The intent is to reduce the risk of
losing all of the PCBs and all of the parts if someone makes a mistake
somewhere: the machines are all automated, but someone has to program
them manually, specifically for our board production.

Cost-wise, after the initial $2600 to $3000 USD for the PCB fab run,
we will need about $1100 for the first Technotronix assembly run ($300
for the stencil + $800 for the 8 boards) and about $1200 for the second
assembly run (12 boards, no stencil cost).  The laser-cut stencil is a
one-time cost, but it will have to be repeated for FCDEV3B V2: we
won't be able to reuse the one from V1 because the V2 change adds one
fine-pitch SMT component (the 74AXP1T34 voltage level translating
buffer), and the SMT pads for this component need to be added to the

However, my main concern is getting the money for the PCB fab run
($2600 to $3000), not the subsequent assembly runs.  Once the PCB fab
order is placed, it will be another month and a half before we'll have
the PCBs to take to Technotronix, and the amount needed for the first
run at Technotronix ($1100) is small enough that I hope to be able to
cover it on my own during that month and a half of waiting for the PCB
fab to deliver.

If anyone here would like to see FreeCalypso progress unblock and see
FCDEV3B V2 become a reality, paving the way for further developments
to follow, and is interested strongly enough to put forth some money,
I make the following offer: if you donate $3000 right now and then
another $1100 a month or two later (after the PCB fab successfully
delivers the PCB panels), you can get two boards from my first
assembly batch.  Yes, I know full well that this deal is not fair at
all in static (time-independent) terms: you would be paying a total of
$4100 and getting only two boards for all that money, two boards which
would regularly cost only $1000.  However, the alternative is to wait
an indefinitely long time for me to cover the upfront costs on my own.
If no one donates and I have to cover the costs on my own, I *will* do
it on my own, and once I have the first batch of boards produced, they
will become available for retail sale for $500 each - however, the
timeframe is completely indefinite in that case, and it could be many,
many months from now.


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