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Connection to the radio


Cables

The radio is connected to the computer using a programming cable. The Links page of the website lists sources of ready-made cables that can be ordered over the Internet as well as several USB/serial adapters and DIY circuit designs. 

If your PC does not have a real serial port and you have a programming cable terminated in a 9-pin serial plug then you can use a USB/serial adapter. 

Alternatively, cables that connect directly to a USB port are readily available.

Be aware that any device that plugs into a USB socket will also need driver software in order to work.

If you have a USB connection that uses the FTDI USB chip then you have the choice of talking to it either by a Com port or through the FTDI D2XX.dll. The D2XX drivers are available here: http://www.ftdichip.com/Drivers/D2XX.htm

The latest RT Systems USB cables have a FTDI USB chip but you need to install their driver software in order to use them. Their cable for the FT-270 is the USB-57B.

DIY information

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 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 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. 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 USB cable as well as other cables based on the FTDI chipset (e.g. the TTL2USB cable).

The screen below shows an RT Systems USB-29B cable being used with an adapter to fit into the 2.5mm socket of the Yaesu CT-91 lead. 



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