Comparing two CW decoding programs.

LY3H CW decoder logic program

MRP40 compared to CW decoder logic by LY3H

MRP40                                                                       CW decoder
1. Decodes all speeds up to 60wpm                            Decodes but not mention top decode speed.
2. Has good documentation                                         No documentation
3. Auto tracking very smooth                                      Auto tracking hunts between long letter spaces
4. Text formatting-format mode works great              Only option is manual or auto decode
5. Will not decode when APF is on                             Will de-code when using APF
6. Great weak signal decode S1 and below                 Poor weak signal de-code (not using APF)
7. Great email support                                                 Upgrades come out regularly
8. See's noise as code sends radium letters                  Only sends letters not radium noise as code
9. Does have save QSO but awkward to use.             Just added cut and paste QSO to word or clipboard
10. Has “always on top” option                                  Just added “always on top” option.
11. Added a mini log book                                          No log book as of yet 
12. You can send code                                                At this time only able to read code                                                     
A more in-depth look at some of the above comparisons:
A)   Auto tracking- When wanting to decode a CW signal it helps when the program can lock onto a signal. MRP40 will lock onto a CW signal and stay locked on. CW decoder on the other hand once the CW signal stops or has long gap between letter the program starts to hunt small segments on either side of the CW signal for other CW signals. Once the code starts again CW decoder has to relock onto it and you lose some decoding. If slow code is sent you are in a battle of lock and relock of the code.
B)   Text formatting options- with MRP40 you have the option on how you want to decode.
- Correct word spacing…..this will attempt to add spacing between decoded words even if sender is running them together.
- Expand abbreviations…..KN, AR and DE to mention a few.
- Expand Q codes…self-explanatory.
Both of these programs do the job of decoding CW very well, you have more options and customization option with MRP40. CW decoder logic is very easy to setup and in no time you are decoding CW. I have not had a chance to compare both programs in a CW contest situation. The major drawback to each program is…..

MRP40…….no matter what test formatting option I used the program when idling would send radium code as it listened to static were as CW decoder logic would not.

CW decoder Logic……when the receiving code stopped the program would start “hunting” for other CW signals. This created two issues, the first being if you are decoding slow code I found the program between letters words would start to hunt. When it does this it bounces back and forth from decoding and hunting and your decode is not reliable. The second is if I second CW op appears close to the op you are decoding the program will bounce between the two QSO’s.
The major positive of each program is…..

MRP40… will decode CW that is almost down at the noise floor and do a great job of it too.

CW decoder Logic……it will not send random letters when it is not decoding and does a great job of adding the breaks between words and not running them together. Also this program is free.

These code programs will always decode what is sent so you must consider if you are reading odd words and letters it may have to do with poor code sending. CW signals that are close to each other (CW contesting) if your rig cannot filter out the one CW signal your decoder will be confused. CW decoder by LY3H free. MRP40 will cost you 50.00 Euro.
You can download MRP40 HERE and you can download  CW decoder Logic HERE
The picture to the left shows MRP40 trying to decode static. 
The picture to the left shows CW decoder Logic and the nice spacing with very few static decodes.
Mike Weir, VE9KK, is a regular contributor to and writes from New Brunswick, Canada. Contact him at [email protected].

21 Responses to “Comparing two CW decoding programs.”

  • Dave, WD8CIV:

    Thank you for the reviews, sir. Morse decoders seem to have improved a lot since I played with them 20 years ago.

    Have you ever tried CW Skimmer? I tried it briefly when my nephew was getting into SWL. I’m curious how it stacks up against these two programs.

  • Harry K7ZOV:

    Nice review Mike. I downloaded this a week ago and played with it a little and was amazed how well it worked. Still has decoding issues with really sloppy fist, but does a good job anyway. I have used MRP40 a few years ago. Not impressed. Using the CW decoder in Fldigi worked just as well for me and whole lot easier…. I know from email with Živlinas that he is far from being done with this program. It will be interesting to see what he does next….

    BTW I sent him your blog link, in case he was not aware of the review. Hope he checks it out and jumps in with some comments….

    73 to you and yours and have a great week.. Harry K7ZOV

  • Harry K7ZOV:

    Mike, a heads up… Žilvinas has informed me a new improved version will be available in a few days. Version that you have works great. It will be interesting to see what he has done to improve the decoder….

    73 Harry K7ZOV

  • Mike W4DL:

    If you need a cw decoder, stay on phone…

  • Neil, w0yse:

    I put cw decoder up against FLdigi in cw mode and found that FLdigi seemed to do just a bit better than cw decoder. Just my brief experience with cw decoder this afternoon.

    Tnx for the info.

  • Harry K7ZOV:

    Mike (W4DL)… Got my Novice in 1963 and never was able to master the code… Now, 53 years later I want to and had to ‘un-learn’ the way I first learned and ‘re-learn’ by doing most in my head…. That said, my right ear is about 80% deaf and my left ear is about 40% deaf. Code faster then 15 wpm have a whole of of holes in it.. So Mr. Mike if you are so good at CW great… But don’t get so snarky and think you know it all… You don’t … A whole lot of people like myself and those learning for the first time would love help with a decoder.. I hope I got my point across… BTW for those of us who do need this added help, Žilvinas, who is writing it, said a improved version will be out later this week. He is hell bent on making one of the best decoders possible…

  • Dave, WD8CIV:

    Harry, according to the FCC database callsign W4DL was cancelled in 2002. Our visitor just likes to rake muck without leaving his own footprints in it.

  • Bart AA7VA:

    I am very rusty on CW (hey, it has been over 20 years since I used it), so I like the backup of using a decoder. Thats for just listening, too rusty to try to key yet —
    The other main point is, what logging programs do they work with? I use DX Labs while many others use HRD etc., and FLDigi and CWGet (running under Win-Warbler) both log with DXLabs – any interfaces for the two covered for extracting logging info?

  • Mike VE3WDM:

    Good afternoon Dave, yes I have used Skimmer in the past but for contests only and it works great. I was using it with the Elecraft K3 along side the LP Pan and an external sound card. I believe Skimmer only stores 10 words so it may be hard to use it for a CW QSO.
    73, Mike

  • Mike VE3WDM:

    Good afternoon Harry always good to hear from you, thanks for passing along the link to the blog post. MRP40 has seen improvements over time and I have found it to be a very decent decode program. Thanks for the heads up as well looking forward to the new release!! I have not tried FLdigi as of yet but want to give it a go and see how it does as well.
    73 Harry and thanks for all the input.

  • Mike VE3WDM:

    Hello Mike, very interesting take on things. I will just leave it at that…… that is all it deserves.
    73. Mike

  • Mike VE3WDM:

    Nice to hear from you Neil and thanks for stopping by, I have FLdigi on my PC but I have not configured it as of yet. From what you are saying about FLdigi I may make this my next project.

  • Mike VE3WDM:

    Hello again Dave, there have been others on this site that feel it is their place to stir up the mud. I have found they are dealt with very fast here on Amateur It comes with being part of the internet and social media.
    Have a great week Neil.

  • Mike VE3WDM:

    Hello Bart, MRP40 will also allow you to send code via your PC if you feel you are a bit rusty. As for the logbook I can only find that it saves the log in ADIF and I imagine you would have to upload that file to your logging program manually. I was not able to find any info were it integrated into any programs as such.

  • Harry K7ZOV:


    73 Harry K7ZOV

  • Brian ve3bwp:

    I very was surprised CW Skimmer was not included in this review.

  • Mike VE3WDM:

    Good afternoon Brain, Skimmer was not in the mix because I not longer have my LP Pan and ext sound card needed for my K3 to work properly with Skimmer.
    73 and thanks brain for stopping by and taking the time to comment.

  • Paul KC2NYU:

    Mike- I gave them both a try and am really impressed with MRP40 to the point I just purchased the Program. I had been using both CwGet and CwWrite – MRP40 does both functions in one program and I think decodes better then CwGet which is very popular. Thanks for the article and the steer.

    73 Paul

  • John Raile W8NEE:

    I want to use this with my G90 for receive only, can I retain decoded in a file for further reference? The G90 does a reasonable decoding job , but, it is 1 line and not retained.

  • Mike VE9KK:

    Good morning Paul, great to hear and I know you will enjoy using the programs.

  • Mike VE9KK:

    Good morning John and thanks for stopping by and leaving a comment. The MRP40 program does store a file of the decoded text. MRP40 calls it a log file but go to the site and download the trial version and get the feel for the program. This way you can see if it fits your needs.

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