Getting Started in PC Soundcard Digital Modes
Copyright © 1999 - 2003 by Harold Melton, KV5R. All Rights Reserved.

AARC MAIN - Technical Index - Icom IC-706MkIIG Page - Sounds of the Digital Modes - NVIS Antennas

February 2003 Update

This entire file has undergone major revision Feb 2003 -- if you saw it before that, browse it again.

Short Version:

This file has become quite long, so if you're in a hurry, here are the bottom lines:

• Buy MixW -- it does it all, for only $50. 15-day free trial.
• Get MMSSTV -- free, has more sstv featues than MixW.
• Don't pay $120 for a soundcard interface that you can build for $15. Put an on-off switch in your desk mic for $3
• Read my new interface section, below.
• HamScope is by far the best freeware. Add IZ8BLY Hellschreiber and MT-63, and MMSSTV (also free), and you'll have the best of all the freeware. If you want everything under one roof, buy MixW.

Whole New Interface Section

See below.

MixW: The BestNew Gottahavit Software!

Things sure do change fast! A new Amateur radio software has emerged that makes most others obsolete.
This new program is called MixW version 2. MixW is the brainchild of Nick Fedoseev, UT2UZ and
Dennis Nechitailov UU9JDR. from Kiev, Ukraine. Don't waste time goofing around -- get the best at go with it.

MixW is a magnificent all-in-one ham radio station program that combines:

• Normal and Contest Logging -- with several statistics displays, powerful enough to be your main/only station log
• Exports ADIF, Cabrillo, and all the popular log formats
• CD-ROM callbook lookup, also internet call lookup (if connected)
• Azmuthal World Map -- shows heading and distance to DX station, determined by callsign
• DDE interface to magnificent DX Atlas software http://www.dxatlas.com/
• Multifunction Tuning Indicator -- Phase Scope, RST, Copy, S/N, IMD indicators
• Waterfall and Spectrum Analyzer -- zoom and colors customizable
• CAT Radio Control -- for many brands and models -- has scan, memories, etc.
• Actual RF frequency can be displayed along waterfall and Spectrum Analyzer, via CAT
• DX Cluster Window -- click the "spot" to jump the radio directly to his frequency (via CAT)
• Keys PTT and CW KEY via CAT; or RTS and DTR pins; can also MCW via soundcard.
• Uses PC-soundcard and/or outboard serial TNCs
• Antenna Control -- for most computer-controllable antenna rotators and remote switches
• Open unlimited simultaneous receive windows -- monitor several signals at once
• Generate QSL CARDS from log data via DDE to WinWord or StarOffice, includes templates
• Almost everything is a toolbar that can be docked anywhere or floated -- design your own screen layout
• All screen colors and fonts are fully customizable
• Can print your callsign in everyone's waterfall in some modes (called "Video ID")
• Contest Voice Keyer -- multimode; uses your WAV files
• CW -- send and receive, works great -- use keyboard; or straight key or iambic paddle on JSTK or PRN port!
• BPSK-31 and QPSK-31 and even FSK-31, a new mode that works even better
• RTTY -- set any shift and any baud rate and use 5, 7, 8-bit character sets -- try new experimental modes
• Packet -- HF, VHF, UHF, Sat., 300 - 19200 baud, simple to configure and use, does not use clumsy external engine, can also digipeat, beacon, ICP/IP (internet) over packet, KISS emulation, all with new internal code. Uses configuration dialog, not clumsy old TNC command line.
• Amtor -- (Mode B (FEC) only) set any shift
• Pactor -- receive only -- G-Tor is in the works
• MFSK-16 -- can send text, files, and even color pictures in a narrowband sstv-like mode
• Throb -- in 1, 2, and 4 throbs/sec
• Hellschreiber -- in three flavors
• FAX -- receive only, any kind, can set any LPM rate, AM or FM demodulation
• SSTV -- in several popular flavors

...all this and more in one integrated interface! The program is very stable -- I have not been able to crash it. Also, it will run on modest computers. I run it with no trouble on a P-133 laptop with only 24 megs of RAM. However, the processor can be overloaded by setting the waterfall too fast, and/or turning on too many digital filters. With a 500-MHz machine and more RAM, you should be able to turn on everything at once and still demodulate while moving the mouse around.

This program definitely isn't flaky-ware. It looks, configures, and performs like high-end commercial software. But the best thing about MixW is its authors, Nick Fedoseev UT2UZ and Dennis Nechitailov UU9JDR. They want feedback and will interact with users' questions and suggestions. Very nice fellows!

Mixw v.3 is in the works.

MixW v.2 is available for free evaluation download. Fully functional shareware, dies after 15 days.
The registration cost is $50 -- VERY reasonable, considering all that it does!
U.S. payments go to Jim Jaffe, WA2VOS, in New York, and he forwards to Nick in Kiev.

Info, see http://mixw.net/
Downloads and registration instructions and payment, http://www.nvbb.net/~jaffejim/downloads.htm GO HERE FIRST.
The help file is a work-in-progress: get latest English help file at http://radioministries.org/k4set/MixW2_help.html
Nick's site from Kiev http://tav.kiev.ua/~nick/mixw/mixw.htm
There are other sites in other countries and languages. Google search mixw.

September 2002 Update Highlights

Packet radio using the computer soundcard: see http://www.qsl.net/soundcardpacket/ for an overwiew and a great site to start with.

Great new FREEware (makes many other programs obsolete/redundant):

MMSSTV, MMANA (antenna analyzer), MMTTY (rtty engine used in HamScope, et. al.), DSP Filter (a cool PC-based DSP audio filter). http://www.qsl.net/mmhamsoft/ .

Drawbacks: MMSSTV None. I have heard users on 14.230 say they like MMSSTV better than the $120 ChromaPix.
MMANA: Nice antenna design program -- except is all metric. These MM's are from Japan.
DSPFilter: Fun toy, not real useful to me. Output runs a little too far behind input on my 500MHz PC.

HamScope -- no, not an oscilloscope -- a most-in-one HF-Digital-Soundcard program: http://www.qsl.net/hamscope/

• PSK31 (BPSK and QPSK, see  PSK31 Home Page )
• RTTY (HamScope uses Makoto Mori's  MMTTY   Engine)
• ASCII (both 7 bit and 8 bit protocols using MMTTY)
• MFSK16 (see  MFSK16 Home Page )
• PACKET (HamScope uses George Rossopoulos' AGWPE Engine)
• Sends CW and receives CW -- and does a pretty darn good job
• Copies two signals (in the audio passband) simultaneously!
• Has multiple spectral displays -- not just waterfall!

Drawbacks: HamScope still doesn't support logging to Logger like all Nino's programs do. Doesn't do Hellschreiber.
CW paddles not supported as in CWType.

Getting Started

Basic info, how-to, and where-to, is on http://www.qsl.net/wm2u. The WM2U website is the starting place for learning about all the new HF-PC Soundcard modes. In addition, http://www.packetradio.com/ has tons of practical info about the new modes, particularly PSK31.

There are many great hamsites with excellent articles and tutorials. Google it by mode name to read the gurus.

2003: I just re-brewed my interface, removing the isolation transformers. They were talking through magnetic fields and causing feedback. If you use isolation transformers, place a steel shield between them. I now use an old Dell P-133 notebook for all radio-computer uses -- it generates no ground loops and very little RF spurs. If you're getting lots of hash, try killing your big CRT monitor. If that's the problem, buy a notebook of a flat-panel display.

Interfaces, 2003 Update

Interface Building

NOTE: See my NEW interfaces on my Icom 706MkIIG Page.

I started with an isloated interface but the transformers talked to each other so now I use a plain interface with two 50k pots in the audio lines, and two simple transistor switches for PTT and KEY. Was also using mic jack but now connected to back of radio, leaving mic plugged in -- added on-off switch to mic.

If your mic is the "always hot" type, put a tiny switch in it.
Switch the output, not the element.

Author's tiny interface. 2 pots set audio levels.
PTT and KEY use 2 transistors, 4 diodes, 4 resistors.

My current interface schematic. Works fine.

Interface Notes:

• Everything at Radio Shack except maybe your radio aux plug.
• "Rx" in the transmit line only needed if you need to load down the mic input some to kill hum. It should be 1 - 5 k or so.
• All goes on breadboard in 3x2x1 plastic box.
• If you want isolated, add 8:600 ohm transformers on the 8-ohm side upstream of the pots -- i.e., the computer output and radio output will see the transformer first; the pots are then in 600 ohm outputs of transformers. Transformers must be magnetically shielded from each other to prevent crosstalk/feedback.
• If you want to use isolated PTT and KEY switching, use opto-coupler IC:
• 
• Use a splice or Y-connector at computer output if also running external speakers. Same for radio, if needed.
• Connect to radio accessory jack if possible, using constant-level line-out and line-in, if available.
• Put a simple on-off switch in the mic and you'll eliminate the need for all that external wiring and mic switching.
• If you're keying a tube-and-relay radio, you'll need higher-voltage devices, like small relays with arc-supression diodes, after the transistors, as well as power supply to transistor switches.
• If using a little plastic box like I did, make slots in edge, not holes, for wires, because, as you can see above, no matter how careful you are, wires will be twisted before you're done.
• Always use stereo mini-jacks for soundcard or you'll short out one channel with a mono jack.
• Buy a Radio Shack 42-2387 6-ft Audio cable with stereo 1/8th-inch jack each end, cut it in half, to run from interface to computer. It costs $3 which is half as much as two good jacks and eliminates the need to solder jacks. The red wire is tip, the black wire is ring.
• Attach the pots so the resistor is across the high-level side and the wiper swings across the low-level output.
• If you get hum on transmit, try shunting the radio mic input side with a 1k resistor. See Rx in my schematic.
• Watch out for sucking your radio mic phantom power down or the preamp in your desk mic won't work. This is usually about 8 volts, with a current-limiting resistor, on the radio mic imput. If you can keep the shunt resistance of the interface quite high without any hum or RF problems, that's better. Switching the mic on will cause it to take priority from the interface because of it's much lower resistance (usually 600 ohms for modern radios).
• If you must use the computer mic-in instead of line-in, use a stereo jack and leave the ring disconnected. This is the computer mic jack phantom power, which normally runs a small electret computer mic.
• Some hums are caused by groundloops. Try lifting the ground wire in the RS-232 jack. Try using an ungrounded laptop computer. If all else fails, install 8:600 ratio isolation transformers in the audio lines. Shield them with steel from each other or they might get a magnetic feedback/crosstalk.
• Most RF problems go away by wrapping the the interface cables through a pair of those square split-toroid chokes. Don't wrap both lines in the same choke or you'll get magnetic feedback through the choke! Put transmit line choke as close as possible to radio. The better solution is to reduce the RF in your shack.
• Check your radio’s manual to see if AF input and output are available on the AUX connector on the rear panel. This is cleaner and more convenient than using mic and external speaker plugs.
• RG-174 teflon makes great shielded audio hookup cable and is sturdier than typical stereo hookup cables.
• Full-function interfaces are available in kit-form for $27.50 or wired for $47.50. Includes opto-isolated PTT, case, cables, all connectors, schematics, and software CD. Order by radio model from http://www.packetradio.com/psk31.htm. This isn't one of the RIP-OFF guys. This is good stuff and the prices are reasonable.

General Operating Notes

• Your soundcard clock may be sloppy. All modes will work better if you calibrate it. Use SSTV or FAX software, tuned in to WWV. Set software to a mode with a scan rate (LPM) that is 60 or some harmonic of 60. Adjust radio so WWV tick paints clearly in software program. Adjust soundcard sample rate so tick line is perfectly vertical. You can get within 1 part per million accuracy if you are patient. Record the new settings and error rate. Apply exact sample rate or error correction PPM to all your soundcard programs that will allow it. MMSSTV has the best soundcard calibration utility I've ever seen.
• Don't use VOX, else you end up with Windows noises illegally on the air (and it irritates the crap out of others). Furthermore, if you use the aux mic input on the radio, and you happen to have the radio keyed (talking), any sound the computer makes will also be transmitted. This may be handy for voice contesting, but otherwise will be playing "music" over ham radio. Any time the computer output is connected to transceiver, you should tuen off all computer sounds. Go to Control Panel, Sounds, and set Scheme to "No Sounds."
• Digital modes that use audio modulation must be completely clean. Do not overdrive! If you see ANY ALC, that’s too much! Dummy-load your signal and listen to it with another receiver. Make sure it's 100% clean. You’ll see dirty, splattering signals on the air, right on waterfall display: A splattering PSK31 signal can interfere with 10 QSOs! Avoid QRO operation. Use modest power that is 100% clean. There must be no clipping or ALC anywhere in the audio chain. Avoid reactance devices that might reshape the waveforms. Never use speech processor or compression.
• Adjust computer mixer volumes to mid-points, then adjust radio mic gain to normal, then AF gain to normal listening level, then adjust interface pots. Do not expect good signals either way if you have pinched the computer mixer way down. The mixer needs to be fairly open so the software can see a large range of binary numbers coming from the soundcard. Don't overdrive the soundcard hardware and expect a software mixer to fix it. Likewise, set the computer audio output at a modest level so the output transistors are always on but well below clipping. Most soundcard software drive the soundcard very hard by sending it the full 16-bit range of numbers. Some allow you to adjust the digital ouput going to the soundcard.
• PC Mixer mixups: Most have two modes: Record and Playback. For INPUTS (mic and line and sometimes aux), the RECORD LINE IN will set the level going into the software. The PLAYBACK LINE IN will set the monitor level. Monitor must be muted if you use VOX, or received audio will loop through the computer and key the radio! (Yes, in spite of antivox). That’s the best reason to build a comm port keying interface, monitor the radio through the radio speaker, and the PC through the PC speakers. PLAYBACK LINE OUT or WAVE sets the output level.

Logging

I do not have much experience with logging software, but if I ever start contesting, I'll just use MixW.

Software: 2003: MixW does it all. Full-featured logger with normal and contest modes, several statistics screens, uses standard ADIF files. MixW can be your main and only logger. Takes input manually and from CAT (radio control connection).

2002 Update: Logger is still the best free logger (IMHO). Unfortumately, HamScope still doesn't write to it directly -- but HamScope does write ADIF files which can be imported into Logger.

Software: WriteLog $75. http://www.writelog.com/.. CW keyer, RTTY, and PSK31 are built-in. Can be networked for multi-op contests. This is called "the ultimate contest logger for Windows." Even has crossed-bananas and auto-tune. I have not tried it.

Contest Voice Keyer

Since the computer is already connected to the radio, automating repetitive voice messages (like "CQ Contest!") is simply a matter of recording wave files and setting some buttons and repeat interval options to play them.

MixW, and several loggers, provide this capability.

The Modes:

CW

Several programs will send CW from the keyboard; two will also accept an iambic paddle connected to the joystick's "fire" buttons (very easy to do). Two ways to key the radio: You can use your interface RTS>PTT circuit to key the radio, with PTT handled by VOX (break-in operation), or you can build two keying circuits, one RTS>PTT and the other, DTR>KEY. The first allows full-break-in (if your radio supports it); the latter is more "elegant." In addition, some programs will also decode CW -- but in practice, the signal has to be strong or at lest, steady (fading will cause it to miss characters that you can still hear by ear). Most CW decoders are easily fooled by static and poor fist. They will never completely replace the trained ear.

2003: MixW does it all. Send/receive CW keyboard, memory keyer, straight and iambic.

CWType, (free) sends code from the keyboard and an iambic paddle (if connected). Has a nice built-in memory keyer, which supports variable character spacing (Farnsworth), and weighting. Is used alone or with companion program CWGet, the decoder, which comes in a free trial version (fully functional but can't save settings), and a registered version ($30).

HamScope: CW send and receive. Doesn't support paddle or key input -- keyboard only.

Can't afford high price of paddles? It's easy to make your own. Mine uses plywood base, brazing rod, and bits of plastic to adjust feel. Can be moved like a bug and/or squeezed. Use a chunk of plastic fishing worm to set your damping and feel. Make feet out of 4 little balls of Coax-Seal -- this will stick key to desk very well. Don't try this design on a boat anchor or you're in for a big shock...

My homebrew iambic paddle.

Another strange design I have not yet tried is the "touch-paddle." This uses a strip of double-sided unetched PC poard set on edge. Each side is connected to gate a JFET. The JFETS key the keyer when you touch the paddle. Nothing moves at all except thumb and finger. That's what you call, "lightest possible touch, with no feel."

PSK31 (Phase-shift keying, 31 baud)

There are several flavors of PSK:

• BPSK (the one normally used)
• QPSK (Quadrature phase shift, slower, more accurate)
• FSK (aka 90/270-degree PSK, a new variant by Nick Fedoseev (MixW) greatly reduces overdrive splatter
• Speeds 31, 63, and 125 (63 and 125 experimental in IZ8BLY Stream)

PSK31 is the most popular digitial mode since RTTY. Much has been written about it. It's relatively cheap and easy to set up and use, and is much more robust than Baudot and other non-ARQ modes. With a bandwidth of 31.25 Hz, it's easy to get 10 QSO's between 14070 and 14071. PSK31 will copy right down in the noise floor -- but any strong signals in the receiver's passband will wipe out weak signals. Mechanical CW filter in the SSB filter slot is very helpful. Use IF shift and notch filter, too.

Some people like to build warblers. That's fine if you just want to build something. Otherwise, use a computer and one of many good soundcard programs.

Set your sound card sampling rate to 11025Hz. Use a 16-bit sound card. Set Rx and Tx frequencies to 1000Hz. NOTE: This value will get you up and running but if you plan on using a narrow IF filter change it to the center frequency. Try using a narrow filter, or crank the IF shift (PBT) all the way down and use 500 or less Hz rx/tx. Strong signals nearby will desense your AGC. Use your notch filter.

Your sound card output must NOT overdrive your Mic Input. Do not overdrive the sound card input from the Radio. Get used to the Waterfall/Phase indicators for tuning. Don’t use Speech Processor or Compression. Keep the drive level below any ALC indication. Don’t use your linear! 50 watts is plenty – this is a 31 Hz bandwidth!  The key to perfect PSK is a pristine signal -- not power!.

Software: The original software for soundcard, by the PSK31 inventor is: PSK31SBW http://www.qsl.net/wm2u/psk31.html. This software works fine but is low on features, so someone made a “front-end” add-on for it called PSKGNR. STREAM (in the PSK31 mode) works so much better! Moreover, STREAM has a giant waterfall FFT tuning display.http://iz8bly.sysonline.it/. Logs to Logger if Logger running. Also has two experimental modes of 64 and 128 PSK.

2003: MixW does three flavors of PSK-31. Can copy 10 QSOs at once.

2002 Update: HamScope does two flavors of PSK. Copy two signals at once (search for next qso while winding up the current one, etc).

Lots of people like Digipan -- I have not tried it but I’m sure it’s fine. It has more automation features than Stream.

Frequencies: 14070 to -071 is very busy; the usual modulation is 1000 Hz, USB. If 14070 drops out, a few people will QSY to 7070. There is a good bit of European DX in the mornings on 28120.

RTTY (Radio TeleTYpe)

Software: 2003: MixW does it all. Set any shift and any baud. Try out experimental rtty modes, make your own.

2002 Update: HamScope does RTTY and ASCII and is free.

I paid the $35 for TrueTTY (from Russia) a couple years ago and it's been worth it.

Notes: Always use Lower Sideband otherwise your signal will be 'inverted' Select ‘reverse’ in TrueTTY because they do it backwards in Russia (where it comes from). Standard 'Mark' is 2125Hz and 'Space' to 2295Hz; shift is 170; speed 45 baud. Remember TrueTTY = LSB Reverse 45 170. Yep, it really works well.

Software: TrueTTY by Sergei Podstrigailo, UA9OSV (has Baudot & ASCII RTTY, Amtor-FEC, and PSK31). Requires $35 registration but well worth it if you like RTTY. The author emailed my key (from Russia) within a couple hours of online payment! http://www.dxsoft.com/ Shareware $35. Fully functional except won’t save configs till registered. This is a very nice, well-featured program. He also has nice Morse decoder & keyer programs, with heavy discount when you buy TrueTTY.

Packet (yes, with a soundcard)

2003 Update: MixW does all flavors of packet, with all-new internal coding. Pretty much obsoletes all other packet systems, except I don't know if it will DDE with WinAPRS (I am asking Nick right now...)

2002 Update: It is now possible to run VHF packet radio, 1200 baud, including APRS, and 300 baud HF packet, using only the soundcard (and, of course, a good isolated interface and a transistor (or optoisolator) PTT switch controlled by the COM port.

Freeware solution: Install latest HamScope. Download AGWPE zip file and unzip it into the same folder as HamScope. Start HamScope and select the Packet mode. It runs the AGWPE packet engine and Voltiare! you're at the Cmd: prompt. Connect the other end of your soundcard interface to your VHF-FM and start looking for packet. The AGWPE engine can be configured to do 300 baud HF packet, also.

The secret is in the software, just like with all the other modes herein. The place to learn all about it is http://www.qsl.net/soundcardpacket/ - a magnificent site!. The software is called AGWPE, which is a software client (or interface layer) which interfaces the soundcard to applications which usually require a TNC. AGWPE will run WinAPRS and several other packet software programs.

Amtor

MixW will do amtor mode-B (FEC) send and receive with a soundcard. I can't figure out why anyone would use Amtor mode B when so many other modes with FEC, like MFSK and MT-63, work so much better...

Pactor, G-Tor

MixW receives Pactor; (G-Tor receive is in the works for version 3). These cannot be transmitted by any soundcard software because they are patented, proprietary modes.

MFSK (Multi-Frequency Shift Keying):

2003 Update: MixW has the usual MFSK-16 mode but you can send B/W and color PICTURES with it, too!

2002 Update: HamScope does MFSK, et. al.

Stream is Nino's (IZ8BLY) MFSK/PSK software. It has MFSK and PSK, several modes each, including experimental modes you can't get anywhere else. It works and looks like all of Nino's fine software.

Common mode is MFSK-16 (multi-frequency shift keying), 1000 Sidetone,USB, on 14.080. Sounds like a kid playing a flutophone.

Stream also runs PSK31, 63, and 125.

Software: http://iz8bly.sysonline.it/  Free. Excellent. Get it. Logs to Logger if Logger running.

Throb

2003: Throb is a strange and little-used digital mode, that I can't currently describe accurately, but several programs do it, including MixW.

MT63

2003 Update: You guessed it: MixW does that, too.

Said to be the most “robust” HF digital mode ever made. 14.347. USB above 9HMz, LSB below. Early morning European activity on 28.130. This is a somewhat broadband mode and is used in the voice allocations.

Software: http://iz8bly.sysonline.it/  Free. Excellent. Get it. Logs to Logger if Logger running.

Read all about MT63 at http://www.qsl.net/zl1bpu/MT63/MT63.html  .

Hellschreiber

Hellschreiber is loads of fun! This is a revival of a very old 1930’s mode which works soft of like FAX. The characters are not decoded by the computer. They are simply painted on the screen on a moving “paper tape” and decoded by the eye and brain. Signals way in the mud can still be read. Lots of fonts to choose from. I have found that Hellschreiber transmissions are hard to locate, but if you just get on 14063 and start sending CQ's pretty soon you'll have a QSO, then another, then a whole party! European Hell is 28110 or 120 in the mornings.

2003 Update: MixW does it all -- well, doesn't have as many modes as IZ8BLY hell.

2002 Update: IZ8BLY Hellschreiber: http://iz8bly.sysonline.it/  Free. Excellent. Get it. Still the best. Logs to Logger if Logger running.

Feld Hell is the usual mode. C/MT Hell will actually paint readable text on everyone’s waterfall display!

http://www.qsl.net/wm2u/hell.html info.

SSTV

Notes: Most xmsns are Scottie-1, a few are Martin-1. Voice (ssb) is used with SSTV to make contact and announce the sending mode, etc. A mic switch is essential. MFJ has one; also their interface has mic switching. SSTVers don't just send blind CQ pictures -- they talk into the group first.

2003 Update: I've tried them all and MMSSTV is my main SSTV program.
MixW does SSTV fine but I prefer the handy features in MMSSTV.

2002 Update: A great FREE program is now available for SSTV/FAX all modes: MMSSTV.

2002 Update: The one and only really great, and FREE!, SSTV software is MMSSTV -- get it at http://www.qsl.net/mmhamsoft/mmsstv/ and while you're there, get his other great free programs -- MMANA, DSPFilter, etc http://www.qsl.net/mmhamsoft/ .

General info: http://www.qsl.net/wm2u/sstv.html

Others are available cheap or free but they tend to use a “Hamcom” type interface, not a soundcard. Yuck.

FAX

2003: Most sstv programs will NOT do HF FAX or WEFAX. JVComm32 is one that does it well, with nice features. Cost money.
MixW has a basic FAX receiver only, no save, no autostart-stop, no scrollback. But you CAN set ANY number LPM.

NOTE: Use FAX mode at 60 LPM to calibrate your soundcard clock to WWV. You can also use SSTV programs that have some mode like WWV calibration, AVT-90 or some other sstv mode with a scan rate that is harmonic of 60.

Bandplan

There is little consensus right now on which modes are acceptable in certain portions of the digital mode sub-bands. The influx of new digital modes and operators is not welcome by some. Please make every effort to avoid interference with other modes.

Bandplan: Practical Information de AD4JE dated Jan 22, 2002

Standard Recommended HF Digital Operating Frequencies (MHz)

North and South America Europe/Africa
3.590 RTTY DX 3.580-3.620
3.605-3.645
7.040 RTTY DX 7.035-7.045
7.080-7.100*
14.070-14.099.5 14.080-14.099.5
21.070-21.100
21.080-21.120
28.050-28.150
* Digital operators should avoid interfering with hams outside the continental US who have phone privileges in this portion of 40 meters.

Recommended Novice/Technician Plus Digital Operating Frequencies (MHz)
28.100-28.150*
Suggested simplex packet-radio frequencies:
28.102.3
28.104.3
* Authorized power output 200-watts maximum for Novices/Technician Plus Licensees in the 10-meter Novice sub-band.

Some of this info is a couple years old - please notify of broken links and inaccuracies.

Partial Rev. Sep. 4, 01
2002 Update Rev. August 28, 2002
2003 Major Rev. February 24, 2003

AARC MAIN - Technical Index - Icom IC-706MkIIG Page - Sounds of the Digital Modes - NVIS Antennas

Copyright © 2002 by Harold Melton, KV5R. All Rights Reserved.