The CCW Archives
 Coherent CW 

Unofficial archive of the works from the early pioneers of Amateur Radio's digital communications era

Maintained by N2APB & the NJ-QRP, with permission from the original CCW archive owner Bill McClune, N3REY


Back in the mid-70's,  I became interested in an experimental mode of digital communications in the Amateur ranks called Coherent CW.  Initially described in QEX, and later chronicled in a dedicated newsletter, the CCW "cult" grew and evolved through many phases and technologies to become what we know today as Binary Phase Shift Keying, or BPSK. Even today's immensely vogue PSK31 is a derivative of the BPSK principles originated back in the days of the CCW pioneers.

This CCW Archive website is a resurrection of a similar one maintained for years by Bill McClune, N3REY.  Bill had collaborated with many of these pioneering digital hams over the years, assisting in their experiments and helping to document the various works that evolved.  Ultimately he had amassed a collection of various written works and article reprints which he posted and made available for years on his personal website, with appropriate permission from the authors and magazine entities.  In time, N3REY's attention was rechanneled and his website disappeared. Before this original archive was lost, I had received permission to capture it and maintain such that others could benefit from the works of the early giants in the field.

The material contained in this CCW Archive is somewhat raw, as many of its documents are unprocessed scans of diagrams and printed material that were done in an age prior to our current electronic documentation conveniences.  I've had a background activity going to clean things up by reformatting and reorganizing, yet still keeping original content.  This restoration work continues and regular visitors to the Archives will notice periodic improvements.

I've also submitted this entire CCW Archive to the ARRL and they are in process of incorporating it into the mainline of their comprehensive technical information web pages.  Until such time as this porting is complete, this NJQRP-maintained website shall remain intact.

Enjoy the rich technical history of CCW contained below -- and hop into the exciting activities of its current incarnations: PSK31, MFSK, CLOVER and many other digital modes!

--George Heron, N2APB
   "n2apb at amsat dot org"

  for the NJ-QRP Club at

What is CCW?

Amateur Radio Coherent CW was invented by Ray Petit, W7GHM.  He is also the inventor of Clover now manufactured by HAL Communications.  The first amateur QSO was by Andy McCaskey, WA7ZVC using a Ten-Tec PM-1.  CCW was promoted by Chas. Woodson (Woody), W6NEY a professor at Stanford University.  Woody published a newsletter in the eary 1970's.  Ade Weiss, W0RSP wrote some articles in CQ and Woody, W6NEY publish a series of articles in QST in 1979 - 1981 period.  In February 1994 VE2IQ published his circuit for CCW using a PC and DSP techniques.  Peter Lamb, G3IRM wrote a newsletter on CCW techniques in the early 1990's. 

CCW moved on to BPSK techniques and is presently being used on 80 meters.  A lot of this work, software, etc. is available on the web. The ARRL had information in the 1980's handbooks and still has some material in the current issues.

Amateur CCW was developed before we had nice microprocessors, DSP and other current technology. It's been around for 25 years, is only as complex as an SSB transmitter, and certainly within the building ability of all most all amateurs.  One does not need power ... it is a QRPp mode. 

CCW is slow ... 12 wpm CW.   You need a good freq standard, but today we can use GPS timing (see TAPR web site). It works in noise and under poor conditions and has been proven to work on the ham bands.

CCW Compendium --  by George Heron, N2APB and Peter Eaton, WB9FLW.  This is a bibliography of over 400 pages of CCW literature, projects, historical happenings, technology evolution, and more.  Some of the references have been mentioned in recent feedback (e.g., QST articles)

CCW - The More You Know About a Signal, The Easier It Is To Copy -- by George Heron, N2APB and Peter Eaton, WB9FLW.  George and Peter wrote a paper concerning CCW that was ultimately presented as two speaking sessions at the 1998 FDIM session at Dayton.  Peter overviewed the rich and colorful history evolution of this low bandwidth communications mode brought about by some ham pioneering giants, and I reviewed the technology and a practical homebrew CCW rig and station. (Partial article ... never finished and not used in FDIM.)

Stealth CW -- by
Stan Wilson AK0B, St. Louis QRP Society Peanut Whistle January 1995.  Stan's article is a wonderful 2-3 page detailed overview of the technology.  (At the moment I can't find the electronic version of his piece, but I do have permission from Stan to post it.)

BPSK article in QRPp -- by Vic Black, AB6SO in QRPp for Vic clearly and succinctly overviews the evolution and current state of the technology, and gives some additional references. 


COHERENT C.W. - THE C.W. OF THE FUTURE PART I, by Adrian Weiss K8EEG/0, CQ June 1977.

COHERENT C.W. - THE C.W. OF THE FUTURE PART II, by Adrian Weiss K8EEG/0, CQ July 1977.


PCW NOTES, by Peter Lumb G3IRM

COHERENT CW PART 1 - THE CONCEPT, by Charles Woodson W6NEY, QST May 1981.


COHERENT CW, Chapter 21 (Special Modulation Techniques), from the ARRL Handbook 1985.

A DSP VERSION OF COHERENT - CW (CCW),  by Bill de Carle VE2IQ, QEX February 1994

Coherent CW for VHF - will it work?, by Don H. Gross W3QVC and Bert C. De Kat VE3DPB

CCW Newsletter -- over 100 separate issues!  

Additional articles/links from Carl, KB0EBG:

CCW DSP Version of CCW by Bill de Carle, VE2IQ (PDF version)

Coherent CW - Part 1 - The Concept by Charles Woodson, W6NEY (PDF version)

Coherent CW - Part 2 - The Practical Aspects by Charles Woodson, W6NEY (PDF version)

Coherent CW - Amateur Radio's New State of the Art? by Raymond C. Petit, W7GHM (PDF version)

The PRECISION CW Handbook by Ernst F. Schroeder

RSCW algorithm for decoding morse code by PA3FWM

Last Modified:  March 2, 2012