Q: What is the short tone sent before some transmissions?

A: Pre-Tones are important to digital networking.  Pre-Tones help prevent doubling.   A Pre-Tone is sent before your message with a brief activation of the fldigi TUNE button in the upper right corner. A brief tone alerts other Ops that you are about to TX.  Wait a second or so after the tone to be sure the frequency is clear. This simple convention will eniminate most doubles.  Doubles are more troublesome in the data modes because both signals are usually garbled.  On CW and Phone, you can often catch enough of the signals to understand some of each.  Not so in the data modes.  Doubling stations must resend and often double again.  Always send a brief pre-tone when doubles are likely.

Q: When keyboarding, I like to compose my message before sending. Isn't this best?

A: Some digital Ops compose their thoughts in the TX buffer before sending.  This insures the message is clear concise and spelled perfectly.  It looks great and sends our thoughts in their best form.  But, it significantly slows the exchange .   While you compose and edit, the other Op or Ops are idle.  On a busy net, these long pauses add up quickly.  Better digital comm strategy is typing into the TX buffer with the transmitter hot.  We all make typos and mis-spell words now and then.  Radio Operators can read around typos and mis-spelling.  Easily.  Or, they’ll question what they can’t copy.

If you’re not doing this now, try it in QSOs with your friends.  They’ll appreciate the brisker pace of the QSO.  Soon, you’ll be comfortable with the tactic.  We don’t like the entire net to see us back up and correct, but it’s more efficient than pre-composing and polishing each transmission.  Soon, your typing and confidence will increase and the skill will become subconscious.  Even though you may type slowly, you will reduce dead-air time. Your digital colleagues will appreciate you (-:

Q: How do I get into the net when I've missed check-in?

A: When you miss check-in, it’s best to monitor until NCS calls for Late Ck-ins.  NCS calls for Late check-ins after the FLAMP exercise and before the Comment round.  NCS also calls for Early Ck-Outs before the Comment round.

Q: What kind of messages are expected?

A:  Message content is not our primary interest.  We practice digital traffic handling; that process is primary.  Messages should be relevant to the Amateur Radio community.  Information about  you, your rig, antenna, projects, and relevant radio experience is useful and welcome.  Again, we’re learning and practicing digital traffic handling.

Formal traffic is normally passed off the net frequency.  For training and practice, we also pass formal traffic on the net frequency during regular net sessions.  In emergency conditions, we would follow the normal traffic net convention of passing traffic off the net frequency.

ORCA passes traffic with the FLDIGI modules, FLMSG & FLAMP.  Both are easy to configure and operate.  We also communicate by keyboard and you are welcome to keyboard during the Comment Round.  Including your station information (QTH,PWR,ANT) in message headers helps others evaluate your signal and current band conditions.

Short messages (<1min) are best, but some messages can be longer.  A good practice is to prepare two messages before net, one short and one longer.  If the net is large or band condx are difficult, send a short message or QRU.  Actual emergency traffic will likely entail long lists and reports.  These files will be segmented into packets by FLAMP, so fills won’t always require sending the entire file.

Small grayscale images are OK for practice traffic if they print in 30-50sec.  Check with NCS before sending color images in the Traffic round.

Keep the mode in mind. Changing from MFSK-32 to MFSK-16 doubles transmission time.  When ORCA is busy, you can skip your traffic for that session and send QRU.

Q: How do I know my place in the rotation order?

A:  NCS transmits the rotation list following check-in.  This is a directed net; NCS calls each station in order.  Please keep the rotation list handy and track your position in rotation.  No Traffic? Send ‘QRU’ in Traffic Round.  Late check-ins are added to the end of rotation.   Monitoring (in&out) stations are not called during net.

Q: What is FLMSG?

A:  FLMSG is a simple forms management editor for the amateur radio supported standard message formats.  It’s data files are pure ASCII text that can be sent from point to point using the internet, amateur radio, or other electronic link. The data files are designed to minimize the transfer size. This is particularly important on amateur HF. The data file and the transfer file are one in the same. The transfer file is encapsulated using a process that is compatible with flwrap. Encapsulation allows the program to confirm the received file integrity.

Q: What is FLAMP?

A:  FLAMP is a program for AMP or Amateur Multicast Protocol.   An FLAMP session will transmit one or more files with one or more iterations of the transmission. Each file is broken into blocks, each of which has a check sum.  The receiving station saves the blocks that pass check sum. Successive transmissions will fill in the missing blocks provided that the new blocks pass the check sum. After the transmission sequence, the entire file is assembled and may be saved.  “Fills” may be provided by resending the entire file or by  sending only the missing blocks.



  • Easy to configure and operate
  • Easy to modify and standardize
  • Operates on Windows, Linux, & OS/X systems
  • Has no need for additional/complex/expensive hardware
  • FREE! Developed and supported by open-source Amateur programmers, for Amateurs
  • Dave W1HKJ, the main programmer, is a dream to work with. He’s added two major features at our request

Q: FLDIGI has been working as configured, but now it's just printing gibberish or not printing anything. Any ideas?

A:   Are you in upper sideband?  Most digital modes use upper sideband and require precise tuning and timing.  Sometimes, within the software and the operating system, a byte or two become corrupted and decoding fails.  Always reboot your OS and then open FLDIGI before the net.  If you are printing gibberish and FLDIGI is configured correctly, try restarting FLDIGI.  If this doesn’t help, try switching to another mode and back to MFSK-32.  Also check your REVERSE setting, squelch, and audio drive.

Q: My SignaLink USB was working perfectly, but now doesn't transmit. I haven't changed anything!

A: This common problem is usually due to the software volume controls being reset by Windows.  This can happen if you unplug the USB cable, or Windows has changed the audio settings while managing other applications.  Other things can cause this to happen as well, so check the soundcard controls carefully.  If Windows has changed the settings, they will likely be set opposite to SignaLink settings, but may appear correct at a glance.  The ‘Speaker’ control should be at 100% (max) and the ‘Wave’ (or “Application” control in Windows Vista and Windows 7) control should be at 50%.  Be sure that your volume control panel shows “USB Audio Codec” or you will be adjusting the PC soundcard.  The SignaLink manual covers this in detail.




International SATERN Digital Net

International SATERN Digital Net transmits digital text, images, and FLAMP files via remote HF station. NCS and Net Manager is Ken Standard AD5XJ.

International SATERN Digital Net

12:00 NOON CT Sat
14.065 MHz USB
OLIVIA 8/500

FEMA Region X HF Interoperability Testing (60m)

FEMA Region X Monthly Interoperability NET, which comprises Alaska, Idaho, Oregon, Washington, conducts a monthly interoperability communications exercise on the 60-meter band. This exercise often includes a voice portion and a digital portion.

FEMA Region X uses the call sign of WGY910. The COMMEX occurs on the third Wednesday of the month from 1730 to 1900Z. Primary check-in is usually on 60-meter channel 1.

FEMA Region X Monthly Interoperability NET

3rd Wednesday 1730Z - 1900Z
Channel 1: 5330.5 kHz
Channel 2: 5346.5 kHz
Channel 3: 5357.0 kHz
Channel 4: 5371.5 kHz
Channel 5: 5403.5 kHz
1730Z Open net, delay check-ins
60M - CH1
1735Z NCS sends 1st dig msg
60M - BPSK31 - CH 2
1740Z NCS repeats 1st dig msg using alt mode
60M - MT63-2KL CH2
1745Z NCS calls for check-ins and reports
60M - CH1
1815Z NCS TX 2nd digital msg
60M - BPSK31 - CH 2
1825Z NCS reTX 2nd dig msg using alt mode
60M - MT63-2KL - CH 2
1827Z NCS calls for reports
60M - CH 1
1850Z NCS closes the net
60M - CH 1

World Clock


Shortwave Radiogram transmits digital text and images on an analog shortwave broadcast transmitter. The program is produced and presented by Dr. Kim Andrew Elliott KD9XB. Shortwave Radiogram continues VOA Radiogram's tradition testing new modes and is an interesting source for Digital Ops wishing to practice more with FLDIGI & FLAMP.

Shortwave Radiogram Transmission Schedule (AM)

Fri 2030-2100 UTC
7780 kHz
9455 kHz
WRMI Florida
Sat 1600-1630 UTC
9400 kHz
Space Line, Bulgaria
Sun 2330-2400 UTC
7780 kHz
WRMI Florida
Mon 0800-0830 UTC
7730 kHz
5850 kHz
WRMI Florida

World Clock