Adding an antenna to the Cheap Yellow Display the easy way

You can exchange the stock ESP-WROOM-32 for the WROOM-32U with a built-in ipex/u.fl connector.

Materials

• WROOM-32U Module
  • Available on AliExpress or Amazon
• SMA Antenna
  • Suggested: Amazon Link
• UFL to SMA Adapter
  • Available on Amazon
• Flux
  • I like Amtech
• Solder Paste
  • I use Mechanic
• Hot Air Station

  Procedure

Step 1: Preparation

1. Setup: Clean your workspace. Secure the board to prevent movement during the process.
2. Flux: Liberally apply flux around the ESP-WROOM module. Struggling? Use more flux.

Step 2: Module Removal

1. Heat Application: Set the hot air station to approximately 350-400°C. Apply heat evenly across the module to avoid damage to adjacent components.

   

2. Remove the Module: Once the solder is molten, carefully lift the ESP-WROOM module using tweezers. If it resists, apply additional heat as needed.

   

3. Clean the Pads: Add solder to the esp pads on the CYD, use solder braid to remove it, clean with IPA, and then lay down solder paste.

   

Step 3: Install the WROOM-32U

1. Position the Module: If you don’t use solder paste simply ensure correct alignment and solder a pin at each corner.
2. Hot Air: If you chose the hot air route, apply heat evenly until the paste flows. After the initial set, apply more heat and give the module a tap with tweezers ever so slightly for it to seat fully.
3. Inspect the Joints: Thoroughly inspect the solder joints for any defects such as cold joints or bridges. A microscope is invaluable for this and many other challenges you’ll face.

Step 4: Reflash Marauder

1. CYM WebFlasher: https://fr4nkfletcher.github.io/Adafruit_WebSerial_ESPTool/

Step 5: Attach the Antenna

1. Select an Antenna: Choose an appropriate antenna for your application. Recommended options are available on Amazon.
2. Connect the Antenna: Attach the UFL to SMA adapter to the WROOM-32U, then connect the SMA antenna.

3. Test the Board: Power on the board and have fun. Don’t be a dick!