Out of stock !   Caused by Microchip shortage.

The Microcontroller ( STM32F103C8T6 ) is not available anywhere at this time.   Now that all of the duplex stock is gone,  there will be no more duplex boards until this microcontroller becomes available again.    When this will be only GOD himself knows.  

This is a Duplex Multiple Mode Digital Voice Modem in a Raspberry Pi Zero HAT form factor. While there are other versions of this type of Duplex board on the market this is the ONLY one which keeps the Pi Zero form factor that has become so popular. This will enable you to keep the portability of the MMDVM_HS_HAT while at the same time allows you to enjoy the benefits of a DUPLEX board. For DMR this means it can have QSO's happening on both time slots.

Note: The photos show the board with u.fl connectors installed.   These are a user installed option.   The pads are there but it is up to the customer to install these connectors. 
  Feature Upgrade :  All boards now have u.fl installed for free!  

Antennas: Two short stubby antennas come with each board.  I also have longer antennas with about 2dB of gain available on the accessories portion of my site.    If you want your board to be supplied with the long antennas,  just order the no antenna option for the board and then add the long antennas as a seperate item.    You will need to order 2. 

Questions? :   Please follow the link in the DOCUMENTATION section.

Note:   This board was designed to be mated to a raspberry PI Zero.   It will work with ALL raspberry PI boards,  however there is a mechanical interference between the right hand SMA connector and the USB connectors on the PI.   There is an easy work around.   Put what is called a stacking header on the PI board first.   You can find right here under Accessories

Additional INFO can be found on the right hand side by expanding that section by clicking on the + symbol.

MMDVM Duplex

  • All the features of a duplex board without having to sacrifice the convenience of the Pi Zero form factor