Note:   This product has built-in antenna,if you need to use external antenna, you should resoldering resistance with soldering iron by yourself.  Step 1: To weld this two parts in blue box.  Step 2: To Fuse the two position selected by the green boxes in the picture.  Step 3: to weld a Resistor.     The results are as follows:  2.4G WIFI Antenna:  SMA connector 2.4GHz 2dBi Wireless WLAN Antenna Aerial.  Gain: 2dbi.  Connector: RP SMA Male (female pin) Connector.  Color: black.  Antenna length: 11cm.     ESP32-CAM-MB Introduction:  The HK-ESP32-CAM-MB module is a small camera module with a size of 39.8*27. This module can work independently as the smallest system. A new WiFi+Bluetooth dual-mode development board based on ESP32 design, using PCB on-board antenna, with 2 high-performance 32-bit LX6CPU, using 7-level pipeline architecture, main frequency adjustment range 80MHz to 240Mhz. Ultra-low power consumption, deep sleep current is as low as 6mA. It is an ultra-small 802.11b/g/n Wi-Fi + BT/BLE SoC module.  HK-ESP32-CAM-MB adopts Micro USB interface, convenient and reliable connection method, convenient to apply to various IoT hardware terminal occasions.     Parameter:  Use low-power dual-core 32-bit CPU, which can be used as an application processor.  The main frequency is up to 240MHz, and the computing power is up to 600 DMIPS.  Built-in 520 KB SRAM, external 8MB PSRAM.  Support UART/SPI/I2C/PWM/ADC/DAC and other interfaces.  Support OV2640 and OV7670 cameras, built-in flash.  Support picture WiFI upload.  Support TF card.  Support multiple sleep modes.  Embedded Lwip and FreeRTOS.  Support STA/AP/STA+AP working mode.  Support Smart Config/AirKiss one-click network configuration.  Support secondary development.     Application scenario:  Home smart device image transmission.  Wireless monitoring.  Smart agriculture.  QR wireless recognition.  Wireless positioning system signal.  And other IoT applications.  Specifications:  Working voltage 4.75-5.25V.  SPIFlash default 32Mbit.  RAM internal 520KB + external 8MB PSRAM.  Wi-Fi 802.11b/g/n/e/i.  Bluetooth Bluetooth 4.2BR/EDR and BLE standard.  Support interface (2Mbps) UART, SPI, I2C, PWM.  Support TF card, maximum support 4G.  IO port 9.  Serial port rate default 115200bps.  Spectrum range 2400 ~2483.5MHz.  Antenna form Onboard PCB antenna, gain 2dBi.  Image output format: JPEG (only OV2640 support), BMP, GRAYSCALE.  Packaging method DIP-16.  Transmit power 802.11b: 17, 2dBm (@11Mbps).  802.11g: 14, 2dBm (@54Mbps).  802.11n: 13, 2dBm (@MCS7).  Receiving sensitivity CCK, 1Mbps: -90dBm.  CCK, 11Mbps: -85dBm.  6Mbps(1/2BPSK): -88dBm.  54Mbps (3/464-QAM): -70dBm.  MCS7 (65Mbps, 72.2Mbps): -67dBm.  Power consumption Turn off the flash: 180mA@5V.  Turn on the flash and adjust the brightness to the maximum:310mA@5V.  Deep-sleep: The lowest power consumption can reach6mA@5V.  Moderm-sleep: the lowest can reach20mA@5V.  Light-sleep: the lowest can reach6.7mA@5V.  Security WPA/WPA2/WPA2-Enterprise/WPS.  Working temperature: -20~ 70 degree.  Storage environment: -40~ 125 degree, <90%RH. Weight: 10g/pcs.