Great Scott Gadgets HackRF - Jawbreaker P31 BANK1_AUX Header; Jawbreaker External Clock Setup; Jawbreaker P2 CLKOUT Header; Jawbreaker P16 CLKIN Header

CHAPTER
TWENTYONE
JAWBREAKER
HackRF Jawbreaker is the beta test hardware platform for the HackRF project.
21.1 Features
• half-duplex transceiver
• operating freq: 30 MHz to 6 GHz
• supported sample rates: 8 Msps to 20 Msps (quadrature)
• resolution: 8 bits
• interface: High Speed USB (with USB Micro-B connector)
• power supply: USB bus power
• portable
• open source
21.2 Set your Jawbreaker Free!
Jawbreaker has an SMA antenna connector but also includes a built-in PCB antenna intended for operation near 900
MHz. It isn’t a very good antenna. Seriously. A paperclip stuck into the SMA connector would probably be better.
You can free your Jawbreaker to operate with better antennas by cutting the PCB trace to the PCB antenna with a knife.
This enables the SMA connector to be used without interference from the PCB antenna.
A video that demonstrates the antenna modification is on YouTube: HackRF Antenna Modification
The trace to be cut is between the two solder pads inside a box labeled R44 in the assembly diagram. There is an arrow
pointing to it printed on the board.
Due to a manufacturing error, there is solder on R44. R44 may appear as a single solder blob. If you have a soldering
iron and solder wick/braid, use a soldering iron and fine solder wick to remove as much solder as you can from the
two R44 pads. Then, use a pen knife to gently cut away the area between the two R44 pads. Make multiple, gentle
cuts, instead of one or two forceful cuts. As you cut, you’ll break through the black solder mask, then the copper trace
between the pads, and stop when you reach fiberglass. Remove the copper trace completely, so just the two R44 pads
remain. Use a multimeter or continuity tester to verify that the two R44 pads are no longer connected.
If you don’t have a soldering iron, you can cut through the copper trace and the solder blob all at once, but it requires
a bit more effort.
The only reason not to do this is if you want to try Jawbreaker but don’t have any antenna with an SMA connector (or
adapter).
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