Download New Windows USB Texting Application

A private texting unit is a small companion radio for a smartphone that allows you to communicate when you have no service or you wish complete privacy and independence from a cellular network. Great for outdoor activities when there is no cellular service, like camping in remote areas or hiking, or when the networks are too congested. They even work onboard a large passenger ship with family members and friends.

Quick Video Demo

• Units available in 915Mhz and 433Mhz versions
• Message received confirmation with automatic retry until message is received or cancelled
• User can select a custom encryption key
• Front panel indicates when message has been received so the phone does not need to remain paired with the PTT
• User can assign any unique telephone number to each unit
• Broadcast message to all nearby units capability
• On screen RSSI shows received signal strength after each text
• ESP8266 32-bit Wi-Fi microcontroller
• Rechargeable 3.7 volt LiPo battery rated at 1200mAh
• 915MHz or 433Mhz high gain 2.0dBi omnidirectional antenna
• The RFM95 transceiver features an integrated +20 dBm power amplifier
• New Extended Range (XR) feature will increase the message range by 20%-30%. Limits bandwidth to only 62 KHz (regular mode is 125 KHz) to achieve longer range and slower speeds
• Attractive black case L 2.3 in W 2.0 H 1.8 in
• Over the air (OTA) firmware updates

This is an open-source ESP8266 application developed using the Arduino tool chain that also utilizes the RFM95 LoRa radio. Owners are free to modify and enhance the ESP8266 application code through the easy to use USB micro connector.

The units provide the same basic functional texting capabilities as several popular commercial products including Beartooth and goTenna, however this is not a Mesh communication technology.

The device functions as an Access Point. You will use your phone’s Wi-Fi capability to connect to the radio (using a customizable password) and then just enter “http://192.168.4.1” into the browser. No need to download a special Bluetooth application.

Specifications

• Compatible with any device with Wi-Fi and browser capability
• LOS (Line of Sight) Range: 2 Miles for Text
• 900 MHz or 433 MHz Digital Transceiver (US Spec: 902MHz - 928MHz)
• LoRa RFM95 Radios
• 2 Day Battery Life
• USB Micro Port With Fast Bi-Directional Charging (2.1A)
• User panel two programmable LEDs, reset button and ON/OFF

Background

This project was a collaborative effort between David Whitney and Michael Phillips (Tindie Sensible Living). Michael was Silicon Valley design engineer who is now retired and living in Sequim Washington. David Whitney lives and works in San Francisco.