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Connection to the transceiver


Cables

The receiver is connected to the computer using a level converter cable. 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.

Cables that connect to a Serial port incorporate a voltage level converter to convert between the +/- 12V of RS232 to the +5V/0V of TTL voltage levels needed by the transceiver.  The cable also converts the 3 wire RS232 circuit (TX/RX/GND separate wires) to the 2 wire GND/TX+RX used by the radio. Do not attempt to directly connect the radio to a RS232 Serial port just by using adapter cables - a proper level converter circuit is essential.

Most modern laptop computers do not have a real serial port. If you have one of these laptops you will require either a USB to Serial adapter to enable connection of the level converter cable, or a level converter that plugs directly into the USB socket (the recommended method). 

If you use a level converter that takes power from the Serial port you may have problems in providing sufficient power to the level converter circuit. This occurs mainly with laptop computers. See here for a test you can perform on the voltage level available at your serial port.

Attaching the level converter to the radio

The radios have a special 4-way socket that has a screw fixing at the top. The plug to fit this is a Yaesu part and is fitted to audio/mic accessories designed for the VX-6, VX-7, VX-120 and VX-170. Be sure to fully screw the cable into the socket or the connectors will not line up and you will not be able to read/write the radio.

The Yaesu CT-91 adapter cable is the recommended way to connect your level converter. The pin-out of the 4-way plug is tip is unused, ring 1 is data, ring 2 is unused, common is GND. 

The CT-91 has two sockets attached to short leads. One socket is 3.5mm and is used for an external speaker. The other socket is 2.5mm and is used for Mic/PTT and cloning. The pinout of the 2.5mm socket is: tip is unused, ring 1 is data, ring 2 is unused, common is ground.



If you already have a cloning cable for a 2-wire circuit then construct an adapter cable to use it with your radio.

Further information on plugs, adapters and programming cables including a DIY circuit can be found on the Links page of the author's website.

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.