Introduction: HackerBox 0042: Worlds of WiFi

Greetings to HackerBox Hackers around the world! HackerBox 0042 brings us the Worlds of WiFi, Antennas, Networking Scanning, and much more. This Instructable contains information for getting started with HackerBox 0042, which can be purchased here while supplies last. If you would like to receive a HackerBox like this right in your mailbox each month, please subscribe at and join the revolution!

Topics and Learning Objectives for HackerBox 0042:

  • Understand RF Interconnects
  • Explore WiFi Networks
  • Test 2.4GHz and 5GHz WiFi Antennas
  • Measure Antenna Performance
  • Assemble and Program a WiFi Scanner Kit
  • Descend into the Circuit Cellar

HackerBoxes is the monthly subscription box service for enthusiasts of electronics and computer technology - Hardware Hackers - The dreamers of dreams.


Step 1: Content List for HackerBox 0042

  • Exclusive HackerBox WiFi Scanner Kit
  • USB WiFi Adapter Dual Band 1200Mbps
  • USB Dock Stand
  • 5dBi Dual Band PCB Antenna with IPX Connector
  • IPX to SMA Adapter Coupling
  • TTL-USB CH340 Module with MicroUSB
  • 1/4 Wave Dipole Antenna Measurement Kit
  • Circuit Cellar Free Subscription Card
  • Circuit Cellar Decal
  • Bitcoin Decal
  • Exclusive Dual-Ended HackerBoxes Lanyard
  • Exclusive "Hack Life Phreak Club" Iron-On Patch

Some other things that will be helpful:

  • Soldering iron, solder, and basic soldering tools
  • Computer for running software tools
  • Wireless Networks to explore
  • Three AA Batteries

Most importantly, you will need a sense of adventure, hacker spirit, patience, and curiosity. Building and experimenting with electronics, while very rewarding, can be tricky, challenging, and even frustrating at times. The goal is progress, not perfection. When you persist and enjoy the adventure, a great deal of satisfaction can be derived from this hobby. Take each step slowly, mind the details, and don't be afraid to ask for help.

There is a wealth of information for current and prospective members in the HackerBoxes FAQ. Almost all of the non-technical support emails that we receive are already answered there, so we really appreciate your taking a few minutes to read the FAQ.

Step 2: Radio Frequency SMA Connections

There are many types of RF (Radio Frequency) Connectors.

SMA or "SubMiniature version A" connectors are precision coaxial RF connectors with a small screw-type coupling mechanism. The connector has a 50 Ohm impedance. SMA is designed for use from DC (0 Hz) to 18 GHz, and is most commonly used in microwave systems, hand-held radio and mobile telephone antennas, and more recently with WiFi antenna systems and USB software-defined radio dongles. It is also commonly used in radio astronomy, particularly at higher frequencies (5 GHz+).

SMA connectors actually have four "polarities" as shown in the image. Reverse-polarity SMA (RP-SMA or RSMA) is a variation of the SMA connector specification which reverses the gender of the central contact pin. The female RP-SMA connector has the same external housing as a standard or conventional female SMA connector, which consists of an outer shell with the threads on the outside; however, the center receptacle is replaced by a male pin. Similarly, the RP-SMA male has threads on the inside like a conventional male, but has a center receptacle instead of the male pin in the middle.


Step 3: WiFi and Antennas

Dual Band WiFi systems, like the USB WiFi 1200Mbps device, operate at both 2.4GHz and 5GHz frequencies. Antennas may be tuned to one of these frequencies, or in some cases both (Dual Band). WiFi antennas generally have a Male RP-SMA connector to couple to the WiFi Device.

The included antennas shown here:

  • 5cm 2dBi 2.4GHz Dipole Rubber Duck Antenna
  • 17cm 5dB1 Dual Band Dipole Rubber Duck Antenna
  • 5dBi Dual Band PCB Antenna with IPX Connector

Note that an adapter connector may be used to convert the IPX Connector for SMA use.

For background on comparing the performance of different types of WiFi antennas, it might be helpful to review the materials for Digital Airwaves HackerBox 0023.

The USB WiFi 1200Mbps Dual Band device is based on the RTL8812BU Chipset.


WiFi Adapters for Wireless Hacking

Hak5's Wi-Fi Hacking Workshop Part 1.1 (and so on through Part 3.3)

Antenna Theory.

Kali Linux is an open source Debian-derived Linux distribution designed for digital forensics and penetration testing. It is maintained and funded by Offensive Security.

Cypress whitepaper on PCB antenna designs.

Texas Instruments whitepaper on 2.4Hz PCB antennas.

Silicon Labels whitepaper on Inverted-F PCB antennas.

Dropout’s Guide to PCB Trace Antenna Design.

Ceramic Chip Antennas versus PCB Antennas.

Step 4: Antenna Performance Measurement

The science of antennas is complex. But the article by Robert Lacoste from Circuit Cellar Magazine shows how the task of measuring an antenna’s performance is less costly and exotic than you’d think. Using a right angle SMA coupler, a Male SMA PCB edge connector, and some 14G wire, you can experiment with a 5GHz version of the 1/4 wave measuring dipole shown in Photo 2 of the article.

Step 5: WiFi Scanner Kit Assembly

WiFi Scanner Kit Components:

  • Exclusive HackerBoxes WiFi Scanner PCB
  • ESP8266 Based ESP-03 Module
  • 128x64 OLED Display
  • 5cm 2dBi 2.4GHz Dipole Antenna
  • Female RP-SMA PCB Edge Connector
  • 3AA Battery Housing with PCB Mount
  • HT7333A 3.3 Voltage Regulator (TO-92 Package)
  • Three pin slide switch
  • Tactile Pushbutton
  • Programming Header (6 pins)
  • Five 4.7K Resistors
  • Two 10uF Ceramic Capacitors

WiFi Scanner Kit Assembly Notes:

  • Observe the placement diagram for component positions
  • Note orientation for the regulator and the ESP-03 Module
  • Gently slide the black plastic spacer off the pins of the OLED
  • Solder ESP-03 module first
  • Solder remaining top components next
  • Closely trim leads on rear of board (wear safety glasses)
  • Lastly, solder battery housing through rear side of board
  • Anchor the battery housing with double sided tape, hot glue, etc.

Step 6: WiFi Scanner Kit Programming

  1. Install Arduino IDE
  2. Install ESP8266 Board Support for the IDE
  3. From the IDE Library Manager, install esp8266-oled-ssd1306 (v 4.0)
  4. Wire up TTL to USB module as shown here (3 wires only)
  5. Supply WiFi Scanner with AA Batteries (not USB)
  6. Open the WifiScanOLED.ino example code in the IDE
  7. Select Arduino IDE Settings as shown here
  8. Power OFF WiFi Scanner (Slide Switch DOWN)
  9. Hold Down Tactile Pushbutton
  10. Power ON WiFi Scanner (Slide Switch UP)
  11. Release Tactile Pushbutton
  12. Hit ARROW BUTTON on IDE to compile and upload
  13. SCAN ALL THE NETS (all the 2.4GHz nets anyway)

Holding down the pushbutton during power-up will put the ESP8266 in bootloader mode allowing it to be programmed by the IDE.

Step 7: Circuit Cellar Magazine - Free Digital Subscription

Circuit Cellar is a premier media resource for professional engineers, academic technologists and other electronics technology decision makers worldwide involved in the design and development of embedded processor and microcontroller-based systems across a broad range of applications. Produced monthly (print and digital), Circuit Cellar provides critical information on embedded, electronics technology and does so at level of depth and detail tailored specifically for advanced professional readers. Their mission is to tackle the key issues of technology to help readers make smart choices with their engineering projects - all the way from prototype to production.

Step 8: Livin' the HackLife

We hope you have enjoyed this month's voyage into electronics and computer technology. Reach out and share your success in the comments below or on the HackerBoxes Facebook Group. Certainly let us know if you have any questions or need some help with anything.

Join the revolution. Live the HackLife. You can get a cool box of hackable electronics and computer tech projects delivered right to your mailbox each month. Just surf over to and subscribe to the monthly HackerBox service.