Software Generated FSK

Software-generated FSK
Updated 01/16/2010

Beginning with WriteLog version 10.58 in early 2006, a new option is available to RTTY operators to generate FSK via a USB-to-serial port adapter. This was not previously possible in earlier versions of WriteLog. With more and more PC's coming out without standard serial ports (COM ports), WriteLog users can now generate FSK via USB-to-serial devices which are generally inexpensive. The only other option is to purchase and install a standard serial port board in which to generate FSK.

Software-generated FSK is available to any COM port installed on your PC. But it's mainly used with the MMTTY plug-in for WriteLog or WriteLog's own RTTY decoder WinRTTY when used with a USB-to-serial port adapter to generate FSK on the TxD line of that port (FSK on DTR now available since this was originally written) . There are several brands and models of USB-to-serial ports adapters. Some adapters are single port while more expensive models offer multiple ports.

Software-generated FSK can be used whether you use a homebrew transistor for FSK keying or a commercial interface such as a RIGblaster Plus or Pro model. The most important step of using Software-generated FSK is installing your USB-to-serial port adapter. When you install a USB-to-serial port adapter, Windows assigns it a COM port number. In some cases, the software used to install the drivers for the USB-to-serial port adapter will inform you which port has been assigned. But in many cases, you are not informed and must find which port number has been assigned in your PC's Hardware Device Manager. And in some cases, whenever you restart your computer, it's possible Windows could assign a different port number than the one previously used. It's always a good idea to double check what port number was assigned. Go the the Device Manager in your PC.

Clicking the plus sign (+) next to "Ports (COM & LPT") will show you a list of COM ports installed on your PC. Find the USB-to-serial port in the list and see which COM port has been assigned to it.

For the purpose of example, COM 5 will be used in this tutorial. A USB-to-serial port adapter has been installed and Windows has assigned COM 5 to it.

Activating Software-generated FSK

1. In order to use Software-generated FSK, you must start WriteLog and choose a RTTY contest module to set up on. If the Rttyrite window did not open when you first started WriteLog, you must open a Rttyrite window from WriteLog's Window menu.

2. When the Rttyrite window opens, go to the Ports menu and select the COM port number which was assigned by Windows when you installed your USB-to-serial port adapter.

3. After choosing the correct port number, the Port menu will close. Reopen the Port menu and choose Software-generated FSK at the bottom of the list.

4. After selecting Software-generated FSK, a window will open asking if you want to configure this COM port for Software-generated FSK. Choose Yes. Your COM port is now configured for Software-generated FSK. To test if your Software -generated FSK port is working, use ALT-K or press one of the Writelog Message Keys (i.e. F1 thru F10) and listen for the tones to be shifting. If the tones are shifting then your COM port is now configured to Software-generated FSK. Note that the TX and TX Off buttons in the MMTTY Control Panel displayed by the Plug-In may not engage the FSK tones.

It's possible when you choose to configure the COM port for Software-generated FSK, you will get a "COM port not available" error. This could possibly be a bug in the program, but this error message can be ignored if you are confident your USB-to-serial port adapter is properly installed and you chose the correct port number in Step 2 above. One way to check to be sure the port is OK, is to go to WriteLog's setup menu and do a "Save Configuration", then save your file. Close WriteLog and then reopen it to the same contest module. If your port is properly configured for Software-generated FSK, you will not receive the error message. If you receive the error message, then it's possible there is a problem with the port such as the port is being used by another program that is running or is configured by WriteLog for another function such as radio control, CW or rotor control. To check to see if the port is being used by WriteLog go to the WriteLog Setup menu and choose "Ports". Check to make sure WriteLog is not already trying to use this port.

Turning Off Software-generated FSK

1. To turn Software-generated FSK off, open the Ports menu in Rttyrite and choose the Software-generated FSK option (if Software-generated FSK is activated, there will be a check mark next to it).

2. The Rttyrite Windows Application window will open asking if your want to configure the port for Software-generated FSK. Choose No.

3. Go back to the Rttyrite Port menu and confirm the check mark is no longer present next to Software-generated FSK. Your port is now freed from Software-generated FSK.