Introduction to FLDIGI Karl Frank, W2KBF Purpose To Provide Fair Lawn ARC members with an Introduction to FLDIGI; Demonstrate Use of FLMSG to send an errorfree text message on an ICS form. (The name stands for Fast Light Digital Modem) 1
Overview of FLDIGI FLDIGI is software that allows a PC to act as a MODEM (Modulator/Demodulator) Input from a keyboard is converted to tones, which are transmitted over Radio Tones received over Radio are displayed as text on the computer Screen A TNC or Hardware Modem is not required Many modes are supported, e.g. RTTY, PSK-31, Olivia, MT63 etc. 2
Why Use Digital Modes? PSK-31 Olivia MFSK-16 Reliable: DSP facilitates communications even during poor band conditions Works with relatively low power (e.g. 30 watts) Many modes (dozens) to choose from Emergency Communications You already have most of the equipment It s fun and interesting 3
How does FLDIGI Work? FLDIGI uses your computer s sound card to generate and decode digital signals (no TNC). FLMSG (and FLWRAP) work with FLDIGI to send and receive error-free messages. Several ways to interface radio with computer, e.g. SignaLink USB, Rigblaster, Skip Teller kit. But in an emergency, can TX with radio mic held near computer speaker and RX with radio speaker held near computer mic (brief demo). 4
Interface by Skip Teller, KH6TY March 2011 QST Provides Isolation between Computer and Radio Provides VOX keying Transformers Provide Isolation between PC and Radio 5
Data Port Mic/Spkr BC-RACES Motorola 440 MHz Mic ICOM 746 Adapted from Harry Bloomberg W3YJ 8 Aug 2012 http://wpaares.org 6
TX Audio Level Adjustment These notes pertain to SSB; FM can be set by ear USB is used on all HF bands, even 40 and 80 Meters Set radio RF output to maximum (e.g. 100 watts) Adjust audio drive to minimum Set radio to meter ALC (automatic level control) Set FLDIGI to center of waterfall display (1500 Hz) Click the Tune button on FLDIGI Increase audio drive until the ALC meter of radio begins to register, then back off until no ALC This will provide an linear, undistorted TX signal May reduce audio drive (or the transceiver power level) for the desired output level (e.g. 20 30 watts) 7
FLMSG for Formal Messages FLDIGI Fast Light Digital Modem FLMSG Automatic ICS forms FLWRAP Calculates a checksum Free software, download from W1HKJ.COM Runs on Windows, Mac and Linux MT63-2000L is relatively fast (VHF/UHF) Olivia-8-500 and MFSK32 are used for HF 8
Formal Emergency Traffic: ICS-213 Requires Pen/Pencil and Blank Message Forms Must speak very slowly and listen carefully Pen and Paper Accuracy is critical if we send: A long list of shelter residents List of required prescription medications Directions to a disaster area 9
What about Throughput? Messages sent by MT63-2000L (~140 bps, 20 characters/second) should be kept as brief as possible due to the relatively low bandwidth Still, at ~200 words per minute, this is much faster and reliable than formal voice messaging FLMSG provides assurance of error-free messaging 10
Summary FLDIGI is free and powerful software Fair Lawn ARC has two HF and one UHF station that can run FLDIGI FLDIGI handout has been circulated with setup information For more information and downloads: http://www.w1hkj.com Demo will follow 11
FLDIGI TIPS BC-RACES Configuration. April, 2015 First download FLDIGI setup from W1HKJ.COM (return later to download FLMSG). Your web browser may issue a warning about the site not being trusted. You may safely ignore this warning. The companion file FLARQ will be installed also. Run the FLDIGI setup wizard (for Windows) -- Fill in requested info, e.g. Name, Call, QTH, etc. When FLDIGI is installed and running, click on the CONFIGURE tab: Operator: You should have this info already from the installation step. Modems: Select MT63 tab. Check 8-bit extended characters (UTF-8) ; Check long receive integration; Check both Transmit Upper and Lower start tones Add a few seconds Tone Duration (e.g. 4 seconds) Check Allow manual Tuning; SAVE these changes, then close. Rig Control: There is no need to enter anything if you are using audio-derived VOX (e.g. SignaLink) or manual PTT to key the radio. If you use serial port PTT (e.g. Rigblaster), then select Hardware PTT and check the Use separate serial port PTT box and select appropriate com port # in the Device box. Sound Card: Select Audio tab. Under Devices, select Port Audio checkbox, then select appropriate Capture and Playback devices, e.g. internal microphone and speakers OR USB sound card (SignaLink or USB dongle). SAVE changes, then close. IDs: Under CW, select Transmit Callsign. BCFMA requests that you send this morse code audio ID when you use the 444.100 repeater. SAVE changes, then close. That covers the basics. If set up properly, FLDIGI will key your rig when you click the TUNE button at the upper right hand corner of the screen. Once you have FLDIGI working, proceed to download and install FLMSG. This co-application works with FLDIGI to ensure error-free exchange of formal messages. MISC: Once FLMSG is installed, start FLDIGI and select MISC tab, then: CPU Tab: If you have a really slow computer (< 700 MHz), click the Slow CPU box. NBEMS tab: Under NBEMS datafile interface, check both Enable and Open Message Folder. Under Reception of FLMSG file, select both Open with flmsg and Open in Browser. Click on Locate FLMSG box and navigate to folder containing flmsg.exe. It probably was installed in C:\Program Files(x86)\flmsg-2.x.x\flmsg.exe. Click on flmsg.exe when you find it... this will update the Locate flmsg box. Then SAVE and close. To operate, select Op Mode, MT63-2000L, then click on 1500 Hz at center of waterfall. The blue T/R button at bottom of screen is used to toggle between TX and RX. If you make a configuration mistake, just restore defaults and start over. Or, you can uninstall FLDIGI, download again, then reinstall. 12