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Connection to the radio

Ready made cables

Please refer to the Links page on the web site for current information on sources of cables. Windows XP, Vista and Windows 7 drivers for Prolific PL2303-based cables are also on that page.

DIY information

The VX-8 uses a 3-wire programming system - separate lines for TX and RX data and GND. This means that 2-wire cables such as those for the VX-7 are not suitable. Also, note that the programming voltage should be around 3V. This may make cables used with the FT-8x7 series of transceivers unsuitable. Check things first before canibalising existing cables. The FTDI cables mentioned below are available in both 5.0V and 3.3V versions - use the 3.3V ones.

The VX-8 has a proprietary 7-pin plug. This picture of the top of the radio shows the socket in the center of the radio.

The pinout of the socket on the top of the radio.

The FTDI 3.3V USB to TTL serial cable 

A dismantled female DB-9 female plug to acquire suitable connectors. You can do the same with a male plug to make matching connectors.

Half of a Yaesu cloning cable (the CT-134). The pins on the wires are from a DB9 male serial plug. Shrink sleeving used for insulation of the pins.

A TTL-232R-3V3 cable with female connections from a DB9 serial plug. Shrink sleeving used for insulation.

Connecting the TTL-232R-3V3 cable directly to the radio using insulated connectors from a DB9 plug. Black to pin 6, orange to pin 5, yellow to pin 4. Use the diagram above for the pin numbers of the VX-8 socket.

The same TTL-232R-3V3 cable as above but with half a CT-134 cloning cable added.

JA1OGS cable built using a CT-M11 and FTDI TTL-232-3V3 PCB - very neat.

To test that a cable works with your VX-8 use the program VX8CableTest which is available on the Download page next to the CommTest program. This will test both reading and writing the radio. Alternatively you can use FTBVX8J to read your radio, but you will need to register it to write.

FTBVX8J and VX8CableTest can use either real or Virtual Com Ports as well as the FTDI D2XX programming interface. This means you can use an FTDI-based cable with or without a Com port number.

COM port connection method

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 shows the result of detecting a Com port:

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. You may not see your COM port if you are running a PDA hotsync program that has acquired all of the COM ports. Stop the hotsync program and try again.

FTDI D2XX connection method

Selection of which FTDI device to use is done using the FTDI cable Detector command on the Settings menu. Use this screen to set up for using an RT Systems cable as well as other cables based on the FTDI chipset (e.g. the TTL-232R-3V3 cables refered to above).

Follow the instructions on the form to choose which device to use.