SM3WMV SO2R Deluxe


After my old SO2R box got ruined by lightning I thought it was time to make a real SO2R box that would fulfill all my needs. I desided to make a box with a LCD on it and a menu system so you can change all the settings etc directly on the box. The only switches visible on it would be for chosing Microphone in manual mode and to switch the audio between the rigs. If one want to change for example the receive mode that is simply done via the menu system. Its based on a ATMEL AVR AT90MEGA128 8-bit RISC processor running at 8 MHz.


USB Either used to control the box from the computer, like W5XD box or if you jumper the box inside you can use it as a simple USB->RS232 converter to control for example a rig.
COM port Used to control the SO2R box externally from the computer, like the W5XD box.
LPT port Used for PTT, Rig A or B automatic selection and CW keying.
RX Audio

  • Auto Headphones follow the radio selected by the computer

  • PTT Allows listening to second radio while first radio is transmitting or the other way around

  • Manual Provides full manual control of headphone audio
  • TX Mode

  • Manual Manually control the microphone/keying with a switch on the box

  • Auto The microphone/keying follows the computer
  • I/O ports
  • Phone input
  • Mike input
  • Key input
  • Paddle input (for LPT keying in the log software)
  • Band data output (from LPT port)
  • 8-pin outputs to each radio containing mike, key,     audio (L&R) and PTT line
  • COM Port to computer
  • Aux COM Port - for conversion
  • USB
  • Line in - Used when voice keying etc with the     computer
  • Line out - Used when recording audio from the radio     (L&R channel)
  • PTT A - Used to identify which radio that does PTT     when using VOX control
  • PTT B - Used to identify which radio that does PTT     when using VOX control
  • Footswitch input
  • DC input - Up to 30V DC voltage is accepted
    Other specs
  • 6 function buttons - Used in the menu system
  • Saves all settings in a EEPROM with a button
  • LCD that is used for the menu system. Menus is made     for example mode switching, baud rate settings etc.
  • USB interface that handles up to 2Mbit
  • USB conversion avaible by jumpering the box and     using the aux COM port
  • Boot loader so firmware upgrading can be done     uthrough the USB or COM Port
    Supported softwares
  • Writelog by W5XD
  • CT by K1EA
  • TR Log by N6TR
  • NA bv K8CC
  • Win-test (Planning on fixing "smart" SO2R support too)
  • And all other softwares that can do A/B selection, PTT     and CW on the com port
  • I will also do softwares for controlling it like the W5XD     box via either the USB or COM port

  • Schematic (All functions aren't tested)

    Preview pictures of the box

    This is the box used in WPX SSB with the main functions implemented. It is a lot of programming to be done before all functions are implemented.

    Inside view of the box taken with a simple webcam

    Inside view of the box taken with a simple webcam

    Picture of the microprocessor, an ATMEGA128 8-bit RISC

    Schematics and PCB layouts will be published as soon everything is tested and works properly. Even the gerber-files will be published.

    To be continued...

    © Copyright 2004. All rights reserved. Contact: SM3WMV Mike
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    Band decoder 1
    SO2R deluxe

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