FLDIGI Users Manual  3.21
Rig Control

Table of Contents

Initial Rig Setup

CAT not enabled

Docked Rig Control

CAT not enabled, Manual Entry of transceiver frequency

Note: The same control is also used for both manual entry of the transceiver frequency or with full CAT control. When no CAT is available the control is simply a convenient way of keeping track of the transceiver USB/LSB suppressed carrier frequency, the mode and the audio tracking point. If fldigi is being used with an FM transceiver you probably should enter the simplex frequency or the input frequency of a repeater being used. This frequency value is used with the waterfall audio frequency to compute the logged frequency. The logged frequency value will only be correct for LSB and USB operation.

The frequency/mode pick list is displayed when the book button is pressed. Pressing the book button a second time will restore the original logging panel.

The pick list buttons control selecting, adding and deleting entries in the frequency/mode list.

The browser list contains frequency, sideband, modem type and audio frequency. The list is saved when fldigi is shut down.

The combo box on the left will allow the selection and control of the operating mode of the transceiver.

The combo box on the right will allow the selection and control of the transceiver bandwidth.

The frequency display is in fact a set of special buttons. Each digit may be left-clicked to increment in frequency by that digit value, or right clicked to decrement by that digit value. The leading digits will follow suit if a decade rollover occurs. You can also place the mouse cursor on a digit and then use the mouse wheel to roll the frequency up and down.

Manual entry of frequency can be accomplished by clicking on any digit and then entering the numeric value in KHz. Don't forget the decimal point if you are entering a fractional KHz value.

The mode combobox, the bandwidth combobox and the frequency display also annunciate the current transceiver status. If you change operating mode on the transceiver, that will be annunciated in the respective combobox and fldigi will adjust any internal parameters accordingly. Fldigi queries the transceiver 10 times per second to maintain a lock step with the transceiver.

Rig Configuration

Hardware PTT control

Hardware PTT control

Right Channel VOX Signal

Fldigi can generate a 1000 Hz tone for the duration of the PTT keydown period. A simple tone detector/filter and transistor switch can be used to generate a PTT signal from this sound card output. Jim, W5ZIT, has provided details on building an interface for this type of PTT control.

Serial Port using DTR or RTS

The simplest rig control is just being able to control the push to talk via an external transistor switch. You set this type of control on the first configuration tab for rig control.

You select this operation by checking the "Use serial port PTT". Select the serial port from the list (fldigi will have searched for available ports). Then specify whether the h/w uses RTS or DTR and whether a + or - voltage is required to toggle PTT on.

You can use a serial port for control with the RTS and DTR pins configured for you particular interface. The program allows you to use RTS, DTR or BOTH for the PTT signal. Press the Initialize button to start the serial port.

Parallel Port (Linux and Free BSD only)

Fldigi sets and clears the parallel port pin, PARPORT_CONTROL_INIT, pin 16 on the 25 pin parallel port connector. Keydown sets Pin 16 to +5 volts and keyup sets the voltage to zero.

μH Router (MacOS X)

Simular functionality can be achieved on the Macintosh operating system using 'μH Router' by Kok Chen, W7AY. See μH Router Website for specific details and requirements. A selectable (check box) option will be available on the Rig->Hardware PTT Configuration panel.

PTT delays

You can accommodate delays in transceiver switching between receive and transmit by adjusting the PTT delays. The control values are in milliseconds. These controls have no effect on external PTT circuits such as those implemented in the SignaLink interfaces. They rely on detecting the audio data stream. You can use a combination of macro tags in a macro key definition to achieve a resolution. For example try a macro definition similar to this to insure that the RSID is sent via a slow FM xcvr (or via a VHF repeater)


Change the idle time value (in fractional seconds) to suit your needs.

RigCAT control

RigCAT control

RigCAT is a rig control system similar to hamlib that was developed specifically for fldigi. It uses command / response definitions that are found in various rig.xml files. You can use a rig.xml file specific for your transceiver or write and test one yourself. The easiest way is to adapt an existing rig xml file for a rig that is similar to your own. ICOM almost identical command/response strings for all of its transceiver line. Yaesu rigs have nearly all used unique command/response structures until just recently. The TS-450, TS-950 and others share a similar set of commands and responses.

RigCAT commands and responses are defined in a rig specific xml file which contains all of the required queries and responses in extended markup language format. Please read the specification document rigxml to learn more about this new way of building generic rig interface definitions and how they are used with fldigi. fldigi will look for a file in the $HOME/.fldigi/rigs directory for all files with extension ".xml". These contain definitions for the transceiver indicated by the file name, ie: FT-450.xml, IC-756PRO.xml, etc. You can download the appropriate xml files from the resource directory tree http://www.w1hkj.com/xmls or from the archives web page. Place the file in your rigs directory and fldigi will find it.

You will need to specify how your PTT will be triggered. This can be using a CAT command, the RTS or DTR pins or none. None would be appropriate if you are using the rig's VOX or an outboard sound card interface such as the SignalLink SL-1+ which produces its own VOX type of PTT. In that case simply leave all of the PTT options unselected.

If you are using a transceiver or a rig interface such as CI-V that echos all serial data you check off the "Commands are echoed" box. That will suppress fldigi trying to respond to a command it just sent to the transceiver.

You may need to try various values of retries, retry interval, and command interval to achieve consistent rigcat control.

Press the Initialize button after setting all of the parameters. If the settings are all correct fldigi should start receiving frequency information from the rig and annunciating them on the rig control frequency display.

Hamlib CAT control

Hamlib is a set of standard libraries for interfacing to a large number of transceivers. The hamlib library system consists of a front end which acts on behalf of all rigs and backends which are specific to each rig.

Hamlib CAT Control

Select your transceiver from the list of supported units. Then select the serial port and baud rate. If you are familiar with the hamlib library you can send various startup sequences to the rig using the advanced configuration. PTT control can be achieved using CAT commands or via DTR / RTS on the same port as the control comms. You might also need to specifiy whether RTS/CTS flow control is uses (Kenwood rigs use this quite often) or if Xon/Xoff flow control is used.

You may need to try various values of retries, retry interval, and command interval to achieve consistent hamlib control.

Press the Initialize button after setting all of the parameters. If the settings are all correct fldigi should start receiving frequency information from the rig and annunciating them on the rig control frequency display.

Xml-Rpc CAT

Xml-Rpc CAT Control

Xml-Rpc allows third party software to control various aspects of fldigi operation including but not limited to rig control. This is the data interface that is also used by the program flrig, a fldigi companion transceiver control program.

If you are using a third party interface such as DxKeeper Bridge you might be instructed to select this method of CAT.

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