[arm-allstar] CW timing question

David McGough kb4fxc at inttek.net
Fri Apr 29 13:06:43 EST 2016

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:


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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