[arm-allstar] CW timing question

Mike - W5JR w5jr.lists at gmail.com
Fri Apr 29 21:09:38 EST 2016


If you slow it down to ~15 wpm, it sounds pretty good. At 18-20, it's unbearable for me to listen to. I've found that changing the source to raise the hardcoded limit above 20 and recompiling results in excellent 20 wpm Morse. Even messages at higher speeds sound great. 

tnx
Mike / W5JR
Alpharetta GA

> On Apr 29, 2016, at 2:06 PM, David McGough via arm-allstar <arm-allstar at hamvoip.org> wrote:
> 
> 
> Hi Tom,
> 
> I've never found the software generated CW to be a "precision" format.  
> Depending of the hardware combo it can be slow, fast or nervous! It was
> plain Schizo on one of my old ACID boxes from yesteryear!  LOL ....On
> RPi2/RPi3/BBB hardware, it is typically fairly well behaved and I believe
> adequate to satisfy the ID requirements. The timing is a compiled
> parameter, requiring a re-compile to adjust.
> 
> Personally, I recommend just using a pre-recorded CW file for high-quality
> results. That's really easy to do, using commands like:
> 
> echo "DE KB4FXC RPT" | tomorse -c 24 -s 20 > kb4fxc-rpt.wav
> sox kb4fxc-rpt.wav -c 1 -r 8000 -v 0.25  kb4fxc-rpt-8kpcm.wav resample -ql
> 
> Unfortunately, the tomorse program isn't installed in our current ARM
> codebase (perhaps in the next release?).  The source code is very small
> and available here:
> 
> https://github.com/mathuin/tomorse/blob/master/tomorse.c
> 
> 
> 73, David KB4FXC
> 
> 
>> On Fri, 29 Apr 2016, Tom Whiteside via arm-allstar wrote:
>> 
>> 
>> This is a nit but I've gotten a couple of comments from CW aficionados that
>> the CW "DAH" timing is about 2.5:1 versus the preferred 3:1.   I may just
>> replace the CW ID with a recorded file but wondered if this was something
>> tweakable?
>> 
>> Tom N5TW
>> 
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> 
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