Introduction
FSQ is a Fast Simple QSO mode for MF/HF. It works well under NVIS and sunrise/sunset conditions on the lower bands, and also works well for short skip on higher bands. It can also be used on VHF FM, and clearly has a much
wider useful range of operating conditions that other more conventional digital modes. Some of the unique features of FSQ are described below.
FSQ is fully open source: the protocol and coding are publicly disclosed. Contact the authors for more information.
Incremental Keying
FSQ uses Offset Incremental Frequency Keying (IFK+), a type of Multi-Frequency Shift Keying (MFSK) with properties which
make it moderately drift-proof and easy to tune. IFK+ also has excellent tolerance of multi-path reception. The symbol rate
(keying speed) is modest (typically about six tones per second), but each
individual tone transmitted carries a surprising amount of information, resulting in a typing speed of better than 60 WPM
in the default configuration.
Very Low Symbol Rate
By using very slow-changing tones, several advantages accrue. The bandwidth required to receive each tone is reduced, increasing the sensitivity and
reducing interference, especially the effects of impulse noise (QRN); the overall transmission bandwidth is reduced, or to put it another way, more tones
can be used in a given bandwidth; and the effect of ionospheric timing changes is much reduced. Special techniques are required to transfer data quickly
at low symbol rates.
Efficient Alphabet
Such a high typing speed at modest symbol rate comes about because the alphabet coding is very efficient. Each lower case
letter and the most common punctuation can be sent in just one symbol, and all others (the total alphabet contains 104 characters) in just
two symbols. This is a simple example of a Varicode, where it takes less time to send the more common characters, which also tend to have fewer errors.
The default character rate is close to six per second, the same as RTTY, but at only 1/8th of the symbol rate (6 baud vs 45.45 baud).
No Sync
Another important factor in the design of FSQ is that no synchronising process is required to locate and decode the received characters.
Lack of sync means that reception is much less influenced by propagation timing changes that affect almost all other modes, since timing is quite unimportant;
and it also contributes to very fast acquisition of the signal (decoding reliably within one symbol of start of reception),
which removes the need for padding idle characters at start of transmission, and leads to a very slick system. Add high
resistance to QRM and QRN, thanks to the low baud rate, and you have a system so robust that it does not need error correction.
Arbitrary Sending Speed
Unlike all previous modes (except perhaps JASON), the FSQ receiver uses no sync process, and operates without needing any information about the sending speed. It will operate from 2 baud
to 6 baud, and anywhere in-between, with no changes to settings. This is completely unique to FSQ, and gives operators great flexibility. The slower
speeds are more robust and slightly more sensitive. Four sending speeds are provided, and the same receiver copies them all!
Chat Operation
FSQ is designed for simple but effective 'Chat' operation, rather like phone text messaging or Skype™ chat: fast and easy to use. This will appeal
to young people used to 'TXTing'. You don't use 'overs' as you would with a conventional digital or voice mode. It is
highly suited to net operation, and operation is very 'slick' (very responsive, with no delays). You just type a sentence and press Enter.
Technical Details
FSQ is like a speeded-up version of the weak-signal mode WSQ2, introduced in 2013. It also uses 33 tones, in this case spaced 9Hz apart (exactly 1.5 x the
default baud rate), resulting in a signal bandwidth of 300Hz, including the keying sidebands (bandwidth assessed according to ITU-R
SM.1138). The ITU Emission Designator is 300HF1B. The modulation is constant amplitude, phase coherent MFSK,
using IFK+1 coding with 32 frequency differences, yielding 32 unique alphabet codes.
This means that each symbol carries enough information for all lower case letters to be expressed in just one symbol, which greatly enhances
the speed.
IFK+ coding means that the character numbers from the alphabet table are added to the most recent transmitted tone number, and ONE is added
as well. The purpose of this added ONE is to force a continual rotation of the tones. This markedly improves tolerance of multi-path
reception (reduces inter-symbol interference), assists the sync-less detection since no tone is ever repeated sequentially, and also assists in reducing the effect of carrier interference. When the resulting tone number
exceeds 33, to keep the tones within range, 33 is subtracted from the tone number before transmission.
There is no 'idle' process in FSQ. Transmission starts with no padding, sends all the available characters, and stops when the buffer is empty.
The receiver can lock to the signal from the first tone, as it measures the distance to the next tone.
Thus the receiver detects and starts receiving the first character in under 200ms from the start of transmission.
The receiving process is a DSP emulation of the familiar 'integrate and dump' detector developed for Piccolo in the 1950s, and uses a high-speed FFT process.
At the receiver, the tones are spaced three FFT bins apart, which gives accurate rounding of the differences when the tone numbers
are decoded and divided by three. This division also reduces the effect of drift and Doppler on the decision process by a factor of three.
There are four alternative speeds (6, 4.5, 3 and 2 baud), although the tone spacing remains the same.
(Default values are shown BOLD).
Unusually for any digital mode, the receiver settings need not change when you change baud rate! Sensitivity is believed to be
about -13 dB SNR at 6 baud, and -16 dB SNR at 3 baud. That's about 10dB better and several times faster than 12 WPM Morse.
Automatic Preamble
Every transmission is automatically identified by the preamble callsign:, so the operator never needs to identify manually.
At the receiver, whatever the sender types appears after the callsign preface.
Character Coding
High typing speed for a given symbol rate is achieved through the use of a highly efficient character coding scheme using Varicodes.
The FSQ alphabet has 29 characters that can be sent as a single symbol (all the lower case letters and frequently used punctuation)
and a further 75 characters using two symbols, encompassing 104 ASCII characters in total.
Lower case should be used wherever possible, as not only are these characters twice as fast as upper case, the probability of errors
in their reception is also halved.
Click the image to view the FSQ Alphabet and Varicode.
It's the same as used in WSQ.
Guided Tour
In keeping with all ZL2AFP designs, the program is uncomplicated to use, clearly laid
out, and devoid of unnecessary features. The software has been thoroughly tested using a team of intrepid enthusiasts, mostly on the 80m and 40m bands,
over 10km to 2500km paths. In this default mode of the program, the simple FSQ protocol is used.
Some menu items describe functions which apply in both FSQ and FSQCALL (Selective Calling) modes, and so are described here. Specific FSQCALL use is described separately in
FSQCALL Help.
Screenshot of the ZL2AFP FSQCALL software with FSQCALL turned off
(Click on image for a bigger view)
Start the program, using the shortcut you made, and after checking the PTT/CAT dialog, you will be able to
see each of the features described
here. At the very top, under the banner, is a comprehensive menu system. It provides the various controls
and setup options, and also allows you to turn FSQCALL on. Here is a description of each Menu item.
File
File/Open Heard station Log
Lets you view a list of the stations heard, in chronological order. The file lists callsign, date, time and SNR.
It is in the form of a CSV file, so you can open it as a spreadsheet if you wish. Logging only occurs while operating in FSQCALL mode.
File/Archive Heard station Log
Lets you archive the Heard Log by automatically changing its name to a timestamped format: Heardlog_YYYY.MM.DD.HH.MM.txt.
The program will then start a new log called Heardlog.txt.
File/File to send
Lets you open a text file to be sent. When you do so, the whole contents of the file is placed in the transmit buffer. Only part of it will be visible
in the TX pane. The maximum file size is 20,000 bytes, and ONLY standard ASCII text files or HTML can be sent. You should not attempt to send extended
ASCII files, word-processor files or any other file types. Once the file is loaded, press ENTER or the TX button to transmit the file. You can stop
(abort) file transmission using the Esc key or by pressing the RX button. Clear the TX buffer by right-clicking in it, choosing 'Select All'
then pressing the Delete key.
You may be able to send word-processor or other files by opening them in their normal application, then copying the text to the clip-board, and pasting directly
into the TX pane. However, the file formatting will usually be lost, and some (unsupported) characters may be omitted on transmission. Many programs cannot be used
in this way, as the pasted versions include control characters, binary data, and/or extended ASCII. For example, you cannot send a PDF document.
In FSQCall mode, you must type the file direction and optionally edit the file name to save in (e.g. zl1xyz#[123]) when you open the file with this function.
20k might seem a fairly paltry file size restriction, but bear in mind that it would take at least 56 minutes to send a file that size! So limit
the transmissions to small text (.txt or .htm) files.
File/FSQCALL Text Files...
Lets you browse the folder containing the text files sent and received using the '#' an '+' triggers.
File/FSQCALL Log Files...
Lets you browse the folder containing the Heard Stations log and FSQCALL traffic logs.
FSQCALL
FSQCALL/FSQCALL On/Off
This is where you turn FSQCALL on and off, obviously. When you turn it on, many internal changes are made to the
program, and the waterfall size is reduced to allow the Options Pane to be displayed. Extra buttons appear.
FSQCALL is a Selective Calling, Linking and Net Management application based on FSQ. Operation of FSQCALL is described separately. See FSQCALL Help for more information.
FSQCALL/SOUND interval
The SOUND function makes periodic brief transmissions (only in FSQCALL mode). This menu item allows you to select 1, 10 or 30 minute sounding intervals.
Under most circumstances you should leave this at the default (30 minute) setting. Sounding allows stations in FSQCALL mode to build a list of active stations, and record propagation and activity information in a log. All
transmissions heard (and verified) are logged.
Suppress TX text when Sounding
Check this to prevent transmitted text from appearing in the TX pane when Sounding is enabled.
FSQCALL/CQCQCQ print ON
Enables messages addressed to 'cqcqcq' to print, just as they would if addressed to 'allcall' or the station callsign. The default state is ON. When disabled,
'cqcqcq' addressed messages are ignored, but those addressed to 'allcall' still print. This applies only in FSQCALL mode. In FSQ mode, everything prints.
FSQCALL/Traffic Log Settings...
Lets you configure the traffic log options. The name of the log file and its format is specified here, and logging enabled or disabled. Logging only occurs if enabled and only while operating in FSQCALL mode.
FSQCALL/Open Traffic Log
Lets you view the traffic recorded in the log, with entries in chronological order. The entries include:
Dir (direction in/out), Date, Time, From (origin callsign), SNR/Speed, Trigger, Message (quoted message, truncated to 250 bytes if necessary).
If the CSV file format was chosen, you can open it in a spreadsheet if you wish.
FSQCALL/Archive Traffic Log
Lets you archive the current Traffic Log by automatically changing its name to a timestamped format: log_name_YYYY.MM.DD.HH.MM.ext where log_name is the current log file name, and ext is its extension.
The program will then start a new log with the file name specified in the Traffic Log Settings dialog.
Options
Options/Callsign...
Sets the user callsign which prefaces each transmission. This is free-form, so could be shortened to 'Ted' or 'Joe' if you wish, and it
can be a mix of upper and lower case. For emergency and event communications use, convenient location or
functional names can be used as callsigns. If the callsign
used is not your licenced callsign, you will need to manually append the
callsign to transmissions every now and again in the usual manner. ID requirements vary according to jurisdiction. Be aware that some countries do not accept
in-mode digital ID, so you may need to add periodic voice or Morse ID. The program does not offer Morse ID.
Preferably, the callsign used and stored here will be in lower case. Not only is this simpler
for other users addressing you to type, and faster to transmit, but lower case text has a lower error rate than upper case.
Options/Location...
Allows you to set your location sentence. This is free-form text, and could be a GPS position, a geographical location,
Maidenhead Locator, street address, or a mixture of all of these. The sentence can only be entered manually (i.e. not directly from a GPS receiver).
This sentence forms the reply to the FSQCALL callsign@ request.
Options/AGC
Allows the automatic AGC in the receiving software to operate in an Off, Fast or Slow
manner. 'Fast' should be better if there is fast fading. 'Slow' is the
default mode, as this best suits rejection of lightning pulses. The AGC affects
the brightness of the waterfall display (keeps it constant), and also
enhances the reception process. 'Off' may be useful when there's ignition or other repetitive pulse noise.
Note: If you can, it is best to operate your transceiver with its AGC OFF or at least FAST, so that
lightning pulses don't disable the receiver any longer than necessary. Don't worry - the software will reject the QRN.
Options/Symbol Averaging
Affects how quickly the FFT data in the receiver decoder is updated. The default is Fast, and that's probably best.
Slow might be helpful when the band is noisy, but may make copy worse except at 2 and 3 baud. We're still working on this aspect.
Options/Peaks "hit parade" count
Select 3 (default) or 6 FFT cycles over which to decide whether there's a new symbol. This mode has no sync -
3 is the default value, suitable for most conditions, while 6 may help when it's particularly noisy or when receiving at 2 and 3 baud.
Display
Display/Symbol marker
This feature 'tags' the received signal symbols on the waterfall with a yellow line as
they are detected. This makes seeing the signal easier when it is weak.
The default state is ON, and you can select the markers ON or OFF. You
may not see the markers when the signal is strong or the Brightness is
high.
Display/Waterfall speed
Allows a choice of waterfall speed; fast or slow (default). More processor power is used by the receiver when this is at the Fast setting.
Display/Waterfall colour
Obvious! Cool blue (default) or bilious green waterfall display.
Display/Text colour
ON means RX text is green, Selcall received text blue, TX text is red, and timestamps are grey, as seen in the RX pane. Off means all text in the RX pane is
black. In the TX pane, text is always dark blue.
Monitor pane text is always black.
Display/10 minute timestamp
This feature is useful if you want to know when someone called or when some test stopped working. It puts a timestamp
in the receive pane every 10 minutes. If reception is happening at the time, it may appear in the middle of
the text. If this annoys you, turn it off and check for the station in the log (Menu File/Open Heard station Log).
Display/Time display
Use this to choose whether timestamps are displayed in UTC or Local time formats.
Soundcard
Soundcard/Audio devices
Allows you to set the audio resources (source, destination, levels) used
for recording (RX) and playback (TX). If you change the audio source
here, it is best to close the program
and restart afterwards, as the program may not notice the change in the
operating system.
To adjust your actual transmit power, use the little applet which pops up when you click on the speaker symbol
on the Tool bar. You may need to enable this from the Windows Control Panel.
Soundcard/Select soundcard...
Allows you to select which sound card is used for reception and transmission. You can change this OK while the program is running.
These settings are remembered for the next session.
PTT/CAT
PTT/CAT
This dialog box sets the COM port used for PTT commands using the RTS and DTR lines, and also for CAT commands.
The default value is that set in the FSQCALvnnn_setup.txt file. This dialog allows you to change port and control method.
For CAT operation, set the COM port to be used here, and select the appropriate transceiver definition. This version supports only a limited range of transceivers. If you have a newer unlisted rig with CAT, follow the instructions
listed under Installation.
Because the same COM port is used for hardware PTT and CAT, when you select CAT, the hardware PTT (RTS and DTR) continues to operate, but will (probably) be ignored by your transceiver.
Speed
Selects transmit symbol rate. The default is 4.5 baud, although under some circumstances
the next highest speed will be usable. The other choices are 6, 3 and 2 baud. The lower speeds are increasingly more robust, and should be used around sunrise and sunset, when signals are more disturbed.
The lower speeds are also more sensitive and handle static much better. You can use 'Options/Peaks/At Least 6' to advantage at 2 and 3 baud. The typing speeds (WPM) in all modes are about 10x the symbol rate (baud).
By the way, the tone spacing is the same in all modes, three FFT bins or about 9 Hz. The transmission is
about 300 Hz wide.
Note: Speed change does NOT need to be matched by any setting changes at the receiving station, which is a remarkable
feature of this mode. Similarly, no changes are made to the receiver by this control.
In FSQCALL mode, the transmit speed can be changed remotely.
Image
Image/Send Image...
Opens the Send Image window used to send and image file to another station.
See IMAGE Help for more information about FSQ image mode operation.
Image/Receive Image...
Opens the Receive Image window used to manually receive an image from another station when not in FSQCALL mode.
See IMAGE Help for more information about FSQ image mode operation.
Help
Help/FSQ Help
Brings up this help file. It is displayed by your default browser.
Help/FSQCALL Help
Brings up the companion FSQCALL help file.
Help/IMAGE Help
Brings up the companion FSQ Image Mode help file.
Help/About...
Displays information about the program, such as author, release date and version.
Text Panes
Receive Pane
Directly below the menu is a large yellow area - this is the Received
Text Pane. Received text is displayed in green, directed text (Selcall) in blue, while
transmitted text is shown in red.
You can also cut and paste text from here. There is a right-click menu here.
Note:You MUST press PAUSE before attempting to select and copy from the Receive Pane.
Transmit Pane
Below the Receive Pane, the smaller pale pink pane displays the Transmit Text Buffer. You can cut
and paste to or from here. There is a right-click menu. When you are done typing, and the channel is clear, press Enter to transmit.
While the transmitter is not running, you can also type ahead and correct what you type with normal Windows
editing functions. The sliders on the right become active when there is more text in the receive or transmit buffer
than will fit on the screen. Being verbose is not encouraged, however.
Nor is trying to type while the previous sentence is being
transmitted. This can cause confusion and missed text.
Other Information and Controls
Waterfall Display
Below the TX buffer is the received audio waterfall display, which has frequency
calibration below, and spans from about 400 to 2200Hz. It shows the
received signals over time, as the waterfall moves down, with older
signals toward the bottom. It moves quite quickly so individual tones can be seen. When the 'symbol marker' option is on, each
recognised symbol is tagged here with a thin yellow line.
Two yellow lines indicate the signal-focussed area of the FSQ modem - the received signals must be completely contained between these marks
or copy will deteriorate markedly. These markers track the FSQ modem center frequency setting.
You should slowly tune the receiver so the whole of any incoming signal is between the red lines. As the signal steps back and forth quite a bit
due to the way signalling occurs, you will need to watch it for a while to ensure it is all contained within the red lines. The lowest tone of
any transmission is the reference frequency. In the case of the default 1500Hz center frequency this will be Dial Frequency + 1350Hz on an SSB
transceiver in USB mode. All other tones are higher than this, by up to 300Hz. Tuning is so easy that
with a modern transceiver you just set the dial to the net frequency, or a round 1kHz step frequency, and forget about it.
Please do not use RIT. The transmit and receive frequencies are always the same.
Note: Tuning needs to be within about ± 50 Hz: if ANY tones fall outside
the red lines, copy will deteriorate quite quickly. It is not really practical to operate FSQ in a net situation
with an older VFO-tuned rig.
Screenshot of the ZL2AFP FSQCALL software with FSQCALL turned off and the waterfall shortcut menu opened
(Click on image for a bigger view)
Right-click the waterfall to open a shortcut menu with options for waterfall settings.
Signal Meter
To the left of the waterfall display is the Signal to Noise Ratio (SNR) meter, which has been calibrated against a simulator to indicate real signal to
noise ratios. There is a thin red line which indicates the level below which Squelch will close
(printing stops). Left click here to change the Squelch level. The meter has light averaging to remove the effect of impulse noise, and operates
quite differently in FSQCALL mode (fast attack, slow release). The peak value
reading is the true signal SNR.
Note: The transmitter will not operate while the Squelch is open! This helps prevent doubling.
If the squelch level is set too low, you may not be able to transmit.
Note: If the Squelch is set too high you may miss some incoming text. When working weak stations,
better to set the Squelch lower, and have a few spurious characters between overs, than lose valuable text.
Speed Meter
Next to the Bright (Brightness) control at the bottom of the window is a small horizontal dotted bar graph, which indicates the sending speed of the currently
received station. It has no meaning in transmit or when there is no signal received. You don't need to match your own transmitting speed
to this reading.
User Controls
Below the waterfall are several button controls and the Bright (Brightness) control. This slider control adjusts waterfall brightness.
Keep it to a minimum to avoid waterfall blurring, and even lower to allow the markers to be seen. The setting is remembered for the next session.
Next, near the Brightness control, just past the Speed Meter, are two dark blue buttons, QTC and QTH. When pressed they flash bright blue, and place any
preset text they provide in the TX buffer. You then need to press Enter as you would normally, to send the message.
You can set this text using a right-mouse-click on the relevant button. You could use the QTC button to set a CQ call or station details.
In FSQCALL mode, the messages behind these buttons can be remotely queried. The QTC (station message) button is normally set to a simple station description,
but can be used for any purpose. The QTH (location) button should contain the station location, either GPS position, Locator or physical address, perhaps all three.
Further to the right are three more buttons. They are the PAUSE button, the Transmit button (TX) and the Receive button (RX).
Each of these is dark blue when not active, and bright blue when active. The program starts in Receive.
PAUSE is used
while editing the screen, as otherwise the cursor will jump around when
you least expect it. It also stops reception and transmission until
either RX or TX is pushed again.
Transmitting and Receiving
Transmit
When you wish to transmit, simply place the cursor in the pink TX pane and start typing. You should type ahead (i.e.
before you start transmitting, typically while the other guy is
transmitting). When you've typed your sentence, and the channel is clear, press ENTER or the TX button, and it will be sent.
If you start the transmitter with an empty buffer, it will send your callsign then stop. This is useful as a 'ZL1XYZ listening on channel'
prompt. As you transmit, the characters sent disappear from the TX pane and
appear in the RX pane once they have been sent. This will let you see the progress of your transmission.
Note:
If you forget to place the cursor in the TX pane, your typed text might not go anywhere useful!
Note: You should only type while receiving. If you continue to type after transmission has started, the transmitter will soon catch up with you,
and if it does, the transmission will stop prematurely. Also some of your typed characters may be missed. Wait
until the program has returned to receive before you type again.
Receive
The program starts in the receive state. You can interrupt a transmission and
return to receive by pressing the RX button. If you press it while text remains in the TX pane, this will not be
sent until you press TX again, and at least one character may be lost.
Normally you should complete typing the transmission text with an Enter key, and wait until all the text appears
in the receive pane, including the new line caused by the Enter, before typing again. Don't worry, you will quickly master the technique, and it will soon seem obvious.
Keep a close watch on the waterfall display during reception, and listen carefully before you transmit, to ensure that
you don't double with someone else. It can still sometimes happen, even with the 'squelch lockout' feature, and if you sense that it has, immediately press the RX button,
or hit the Esc key, so your transmission stops.
Watch the signal SNR on the meter (bottom left). You will probably find
that the signal fades up and down by 10dB or more, and print may stop or
become garbled during fades. Reduce the Squelch level if this happens.
It's better to have a few garbage characters than miss real text. Keep sentences short, and
stick to lower case and CW-speak abbreviations to maximise typing speed.
Pause
The PAUSE button stops both transmission and reception.
It is best not to edit text during transmission, although you can delete typed characters (using Backspace), after and including the error,
then retype. The problem is that this simple program does not remember cursor locations,
and the transmit and receive panes share the same cursor control. Thus it happens that when you move the cursor manually
(click in the text with the mouse), you may find the software promptly moves the cursor
back to the end of the typed text. During transmission the program may miss your keyboard strokes, so
again, typing while transmitting is not encouraged.
In FSQCALL mode it is bad practice to edit the text (or add further text) while transmitting, as this then messes up the Smart Squelch.
Another problem with editing while transmitting is that the transmission will stop when it catches up with your typing - can you really
consistently type faster than 60 WPM?
The most reliable way to edit the transmit buffer text (i.e. edit by moving the cursor insert position) is to do so while receiving, and
press the PAUSE button in order to do so. Then press TX or RX again as appropriate.
Note:
You can copy and paste from the RX pane to the TX pane, so if you want
to call CQ again, or have a request to repeat what you've just sent,
simply copy the text from the upper pane and repaste it in the lower
pane.
Escape
It's not so convenient to move the mouse to the RX button if you need to stop transmission in a hurry, so the software
provides a keyboard 'abort transmission' function via the Esc key, which has the same effect.
This feature is very useful if you sense, just after starting a transmission, that someone else has just done the same.
If you are quick, you won't miss much of their transmission, and you will probably not lose many of your own transmitted characters either,
and any that have already gone will be easily replaced by moving the cursor to the start of the TX buffer and typing them again (you don't need to retype the automatic preamble - and in fact delete what's left of it before retransmitting).
Software Compatibility
The Windows™ software is written in ANSI C, and is compatible with Windows Vista, WinXP and Win7. The program requires at least a 1GHz
processor, SVGA display and a 16-bit sound card. A Pentium 2 class or better is suggested. One serial port (or
USB equivalent) is required for PTT or CAT control. Memory requirements are
minimal, and the program size is about 200kB.
The program window is small, and fixed in size, allowing you to use a laptop or netbook with a modest screen, or allowing room for other applications on the screen.
The program consists of just one file, and no changes are made to the
computer's registry or anywhere else. To remove the program, simply
delete the files made during installation. A setup file is made in the
working folder. A new setup file is used for each new version, so you can install new versions to the same folder.
CAT functions have had limited testing due to lack of suitable rigs. CAT is known to work with Icom, and some Kenwood and Yaesu rigs,
but we could do with assistance testing other transceivers.
Developers interested in writing software for FSQ and/or FSQCAL should contact
ZL2AFP (zl2afp "at" xtra.co.nz) for source code and other details.
Credits
The original idea for Incremental Frequency Keying came from Steve VK2XV/VK2ZTO
'Sync-less' peak-hit counting FSK was first suggested by Alberto I2PHD (and used in JASON)
The 'unsquare' 28/32 WSQ Varicode and the general WSQ and Chat concept were dreamt up by Murray ZL1BPU
The FSQCALL protocol was developed by Murray ZL1BPU with significant input from Con ZL2AFP, and is an all-new retro design
All the hard work was done by Con ZL2AFP, following many years of development of MFSK modes, including DominoEX of course
The "US Edition" contains modifications and features by Mike KA4CDN and Bob NW8L
Copyright © Murray Greenman and Con Wassilieff 2013-2015.
All rights reserved.
