Monday, December 10, 2012

Best Morse Decoder

For several years now  I have been of the opinion that the best Morse decoder for Windows PCs is MRP40 by Norbert Pieper. A few days ago Paul PC4T commented to one of my posts that he thought CW Skimmer was better so I thought I would give it a try in case I was missing out.

MRP40 decoding some Morse
I ran both programs simultaneously decoding the same signal. After listening to many QSOs I am still of the opinion that MRP40 is the best decoder. It decoded text more accurately and the spacing between words was better - CW Skimmer would often run words together then insert a space in the middle of a word. Skimmer also seemed on occasion to insert an spurious E at the beginning of some words or calls when I didn't hear an extra dit.

MRP40's decoder is less laggy than CW Skimmer's - text appeared sooner after it was sent. I also found MRP40's AFC useful in locking on to signals. It could track drifting stations and would adjust itself precisely to the signal if you didn't click exactly on the trace. CW Skimmer seemed more fussy and didn't decode a signal unless you got it spot-on. This is perhaps understandable given that Skimmer is intended to be able to distinguish between multiple signals in a pile-up.

CW Skimmer is the better program if you want to decode all the calls in a swathe of spectrum and if you want to link to your logging program so as to highlight new countries or prefixes and mark stations you've previously worked. That is, after all, what it has been designed to do. But as a morse decoder pure and simple MRP40 is still the winner in my book.


Paul Stam PAØK said...

Hi Julian, as you probably know by now: I do agree with you. I tested MRP40 and CW Skimmer simultaneously and for me was CW Skimmer the winner. It will never let me down. When read eHam reviews you see that other amateurs think the same. MRP40 get 3.9/5 and CW Skimmer 4.4/5 and this is what ON6KE wrote about: I have CW Skimmer installed for several years now, it's a great help during contests.
I ran across MRP40 the other day and thought why not try it out side by side with CW Skimmer.
It doesn't even come close to CW Skimmer:
1. no simultaneous decoding, CW Skimmer does 100's, MRP40 just 1
2. decode is inferior to CW Skimmer
3. set level required on 'oscillogram'
4. text formatting is dated
5. fixed size windows
Glad I didn't put my money on MRP40 so many years ago.

More reviews can be found here:

So, I am glad not to spend money on MRP40 because CW Skimmer is highly over priced already. That's the only negative point about it, still I don't regret I bought this fine software.

73 Paul

Paul Stam PAØK said...

Hi Hi... I meant: I do not agree with you. Freudian mistake? 73 Paul

Anonymous said...

Hi Julian,

have you ever tried Digital Master 780 (part of the Ham Radio Deluxe suite) as CW-decoder? If you do, how does it perform compared to MRP40?
I usually let DM780 run in decode mode on the background for when I miss something.

73, PA1JIM, Jim

Unknown said...

Hi Paul. I was scratching my head... Still I think the internet is a big enough place to have different opinions.

Jim - No I have not tried DM780. However according to Simon Brown the decoding routines in 780 are the same as in fldigi. I have tried that - it's not bad but not the best.

VE9KK said...

Good morning Julian, I have tried and am thinking of purchasing MRP40. I did find it to decode very well but I have not been able to get Skimmer to work as of yet but I plan to get it up and working with the KX3. I will see how they compare with my antenna and QTH situation.

Unknown said...

Hi Mike.

I will be interested to see your thoughts. I haven't deleted Skimmer from my PC yet so I will continue testing. Unfortunately I discovered a bug in KComm this morning - darn thing locked up in the middle of a QSO!

Julian, G4ILO

Paul Stam PAØK said...

Hi Julian, of course there is space enough on the Internet for different opinions, I do not doubt that. But I am surprised that your outcome is different, because I tested both and all other decoders. For me is CW Skimmer the best. Especially for weak signals, that's where MRP40 fails (in my opinion). But good for a second place.
In Digital Master 780 and Fldigi the CW decoders are lousy and it is a shame that is a part of the software.
The best CW decoder is the human brain and ears, but you'll have to train it first to obtain the skills. CW decoders are only a little help. I will never rely only on a CW decoder.
73 Paul

ag1le said...

Hi Julian

Have you tried FLDIGI CW decoder yet?

It is free and source code is available to make improvements. I have done some improvements, and I am currently testing some new algoritms. See for details.

73 Mauri AG1LE

Unknown said...

Hi Mauri.

I tried Fldigi on CW a few years ago. Looks like I should try it again soon. Thanks for the info.

Julian, G4ILO