An Yaesu FT-897, FT-857 and FT-817 transceiver - PC Interface (YFPI)

                                                                                

  1. Foreword
  2. Project schematic, PCB layouts and data sheets
  3. Software for Amateur Radio digital modes
  4. Pictures

 

A picture of my YFPI project will be coming soon

 

Foreword

This YFPI interface is used to fully control a transceiver from a personal computer. It is used to transfer sound between a transceiver and a personal computer and vice versa too, when operating Amateur Radio digital modes as BPSK31, SSTV, CW, JT6M, RTTY and many more. The related software has to be loaded and running on a personal computer.

The YFPI interface can be used to handle all kind of transceivers having a TTL interface (0 and 5V) and wants to be controlled by an ordinary RS-232 interface from a COM PORT on a personal computer.

The YFPI interface has just one galvanic grounding wire between the used transceiver and the personal computer. The advantage of this is completely elimination of 50Hz/60Hz hum - coming from the main power system. The 50Hz/60Hz hum is a well known LF-problem when more then one grounding wire is connected between two pieces of equipment.

How is it possible to use just one grounding wire:

  • Sound from the transceiver to the personal computer is galvanic isolated by a transformer (second hand from an old 56k modem)

  • Sound from the personal computer to the transceiver is galvanic isolated by a transformer (second hand from an old 56k modem)

  • Activating of the PTT or CW, from the personal computer, is galvanic isolated by a CNY17 optocoupler.

  • The single grounding wire is used in the handling of the very simple CAT data interface.

Project schematics, PCB layouts and data sheets

Software for Amateur Radio digital modes

Pictures

Pictures of my YFPI project will be coming soon