HamShield Mini Pinouts

Looking for HamShield Mini? You can buy it here.

The HamShield Mini is our smallest HamShield yet, and is 100% compatible with the HamShield Library. It can transmit at 200mW, its small, can work at 3.3V, and has lower power consumption compared to HamShield 1.0 -- making it ideal for portable operation or CubeSats!

The HamShield and HamShield Mini feature a special serial bus used to communicate with the AU1846S radio transceiver IC. The pinouts are as follows:

Communication Header (shorter header)

This is the most important header on HamShield Mini. It provides power, audio connections, and a serial data connection for controlling the radio IC.

 Pin Number Function Description
1 SPKR Connect to analog input on microprocessor
2 MIC Connect to analog output or PWM if microprocessor
3 CLK Serial Clock
4 CS Chip Select
5 DAT Serial Data In / Out
6 GND Ground connection
7 VCC Power between 3.3V and 5V


GPIO Header (long header)

This optional header provides access to a variety of useful functions on the AU1846S. It is directly tied to each of the GPIO lines. They are not level shifted, so please keep logic levels at 3.3V. The AU1846S can provide COR functionality, signal reception and transmission indicators, valid CTCSS tones, and more. Be sure to check out the HamShield library for more detail on some of these functions.

 Pin Number Function






10 GND


Additional Audio Connections

A small 4 pin header offers direct access to the TRRS port. You can plug an optional TRRS Crossover Kit in this header to connect HamShield Mini to another audio source (ie: putting the speaker into the microphone and vice versa of a phone, computer, or another HamShield), connecting to a loudspeaker, or you can come up with your own applications!

Pin Description
 1 Microphone In to radio
2 Left speaker (disconnected by default)
3 Right speaker (audio from radio)
4 Ground


Pro Tip: Shorting pin 2 and 3 can provide monaural output, for HamShield audio on both headset speakers. This will reduce volume slightly, as the amplifier will have to drive both speakers.

Additional Resources

HamShield Mini Hardware Design on Github

HamShield Mini Schematic

HamShield Library

HamShield Mini on the Enhanced Radio Devices Store

The Original HamShield 1.0 on the Enhanced Radio Devices Store