[RTTY] 2 tone vs MMTTY

[Kermit (aka Ken) via RTTY]

Hi,
 
This was a thread a couple of weeks ago, just when I got kicked off the  
reflector for too many bounces (due to my efforts to filter out the horrendous 
 crap and clutter at that time).  I had wanted to mention TrueTTY as 
another  useful decoder, although it cannot be used in N1MM.  I find it falls  
somewhere between 2Tone and MMTTY.
 
I've used fldigi too, but have had trouble using it in N1MM where sometimes 
 it stops decoding for some unknown reason.   In my experience the  
decoders I've tried fall thusly:
 
2Tone > TrueTTY > fldigi = MMVARI > MMTTY
 
but, as I've said before, on any given transmission it's a crap  shoot.  
 
73,
Ken, AB1J
 
 
In a message dated 2014-06-12 6:56:06 A.M. Coordinated Universal Tim,  
ed at w0yk.com writes:

Meanwhile, many of us run multiple parallel decoders to approximate  this
more elegant approach.  ;>)

Ed  W0YK

---------------------------------------

On Jun 11, 2014, at  9:00 PM, Ed Muns wrote:

>  OTOH, that part of the decoding  algorithm is probably key to
> 2Tone's excellent copy of weak and other  marginal signals.

Chen W7AY wrote:

The trade off between a  "low-latency crummy decoder" and a "high-latency
better decoder" can be  solved if you allow new GUI elements into your 
modem.

Run two  demodulators.  The low-latency one prints first.  The  high-latency
decoder then overprints over those characters when they become  available
from the high latency decoder.  This way, your eyes do not  need to switch
its focus between two windows.  Strong signals will  print correctly right
away.  

Variations on this theme include  using two different color fonts that
produces a third color when the two  decoders agree, etc.

I had discussed this technique before with G3YYD  for making even longer
latency decoders tolerable (for example, ones that  corrects bit clocks by
using "future" bits for pseudo-synchronous  clocking).  But David is hobbled
by the existing modem user  interfaces.

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