What is it?  
This is a breakout Printed Circuit Board for a SA818 transceiver module.  
Why did you make it?  
I am a licensed Radio Amateur and building electronics is part and parcel of the culture. I have wanted to construct a radio using this module for some time and successfully built the shield for an OrangePi zero published by VoltNode. A great design but designed exclusively for the OrangePi. I wanted to be able to interface any MCU to make programming the module easier, hence the PCB here. If you are interested in purchasing this PCB, please visit my Tindie store.  
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What makes it special?  

It is a very simple low cost design, that can be controlled by RaspberryPis, Arduinos and Pico's etc.

 
   
   
 

Connections are:
Pin 1 [.] 5V
Pin 2 3.3V
Pin 3 GND
Pin 4 UART TX
Pin 5 UART RX
Pin 6 PTT
Pin 7 SQ
Pin 8 Audio Out !Marked AIN on PCB!
Pin 9 Audio In. !Marked AOUT on PCB!
Pin 10 GND
Pin 11 GND
Pin 12 GND

 
 
There is an updated version of this PCB which allows provision of a PTT Button and better connection labelling.  
 

The below image shows a populated PCB with an SA818V module.

 
 

The below image shows a PCB connected to a Pi 3 A+ and with an audio out socket.

 
 

Parts needed are:
1 x SA818 Module (or DRA818) U or V.
1 x SMA antenna pcb connector.
1 x SMD Filter 0500LP15A500E.
1 x SMD BC847 Transistor.
1 x SMD BC857 Transistor.
1 x Red LED.
1 x Blue LED.
1 x Green LED.
1 x IN4001 Diode.
3 x 470nF Capacitor.
1 x 0.1uF Capacitor.
2 x 330R Resistor.
1 x 470R Resistor.
4 x 2.2K Resistor.
2 x 1K Resistor.
3 x 10K Resistor.
2 x 47K Resistor.
1 x 4.7K Resistor.
1 x 12 way connector strip.
1 x 3 way connector strip.
1 x bridging link for above.

 
I sell on Tindie  
(c) 2021,2022,2023,2024 Paul Bartlett