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Connection to the radio


The Links page of the website lists sources of ready-made cables that can be ordered over the Internet as well as several DIY circuit designs. 

If you already have a programming cable for a Yaesu radio that uses a 2-wire circuit you can make an adapter to plug into the microphone socket. Pin 4 is ground and pin 6 is data (see page 48 of the user guide).

Direct USB port attachment

Cables that connect directly to a USB port are available from a number of sources in the USA, UK and Europe. This type of cable is directly powered from the USB port and is the recommended means of connection.

9-pin serial port attachment

Connection to a 9-pin serial port can be achieved using a cable such as the RT Systems CT-29F. This is the cable supplied with the ADMS programming software for the FT-1500.  

The CT-29F cable incorporates a voltage level converter to convert between the +/- 12V of RS232 to the +5V/0V of TTL voltage levels needed by the transceiver.  It also converts the 3 wire RS232 circuit (TX/RX/GND separate wires) to the 2 wire GND/TX+RX used by the radio. 

If your level converter takes its power from the serial port (as does the CT-29F) you may have problems in acquiring sufficient power for reliable communication - particularly with laptop computers. See here for a test you can perform on the voltage level available at your serial port.

Voltage level from the programmer

The author found that the voltage level across pins 4 and 6 had to be 3.6V or more before reliable communication could be achieved with his FT-1907. To measure the voltage on your programmer plug the cable into your PC leaving the RJ12 connector free. Run the program. Click the Read Radio button and then check the voltage.

COM port

Selection of Com port number is done using the Settings menu. The program will remember the selection you make for the next time you run. 

There are two commands available - 'COM port Detector' and a pop-out called 'COM Port'. If you are certain about your COM port number then it is quickest to use the 'COM Port' pop-out. Otherwise use the 'COM port Detector' command. The following screen is shown:

Follow the on-screen instructions to detect and set the COM port for your programming cable. Be aware that each USB socket on your PC will be allocated a different COM port number, so you may need to use this screen again if you change your usual socket.