README
Copyright 2012 - 2016 Great Scott Gadgets

These files are part of HackRF.

This is a free hardware design; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.

This design is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this design; see the file COPYING.  If not, write to
the Free Software Foundation, Inc., 51 Franklin Street,
Boston, MA 02110-1301, USA.


Opera Cake is an RF switching add-on for HackRF One.

hardware notes:

Schematic and layout files were designed in KiCad, an open source electronic
design automation package.

order of copper layers:
    Copper 1:  C1F (front)
    Copper 2:  C2
    Copper 3:  C3
    Copper 4:  C4B (back)

PCB description: 4 layer PCB 0.0646 in
    Copper       1:  1 oz copper (1.4 mil)
    Dielectric 1-2:  6.7 mil prepreg
    Copper       2:  0.5 oz copper (0.7 mil)
    Dielectric 2-3:  47 mil core
    Copper       3:  0.5 oz copper (0.7 mil)
    Dielectric 3-4:  6.7 mil prepreg
    Copper       4:  1 oz copper (1.4 mil)

FR408 or similar substrate with Er=3.66 (+/- 0.1)
double side solder mask green
double side silkscreen white
6 mil min trace width and
6 mil min isolation

PCBs of this specification are available from OSH Park.