Make your own high performance QRQ CW KEYBOARD with the RASPBERRY PI

[Chuck aa0hw]

This video demo's a Raspberry Pi being setup as a high performance morse code cw keyboard that keys a rig with just the analogue audio output sound card of the pi...where the pi's audio output goes to 2 individual audio derived cw keying circuits which in tandem key both the PTT first on the K3 and then the CW JACK on the K3.

you need to add this repository to get the audio apps demo'd:
https://www.raspberrypi.org/forums/viewtopic.php?t=37011&p=903225
http://wiki.linuxaudio.org/wiki/raspberrypi#audio_software_repository

FOR QRQ OPS:
On the K3, when the PTT is activated first, the cw timing is much better and the K3 will still key cw accurately, even up and over 100 wpm...otherwise, when keying just the cw jack on the K3, the cw starts having trouble around 90 wpm on my K3 AND there are many first dits that are short when just using the CW JACK.

The PTT feature of this setup will hold the PTT for another 25 milliseconds after the CW JACK is finished keying.

This combo should work well on other rigs besides the K3 too...

NOTE: both pulseaudio and jack audio connection kit are used to make this work... TWQRQ uses pulse audio, and everything else uses jack audio connection kit

APPS BEING USED:

TWQRQ
send an email to TED wa0eir for a beta version copy of this program

PULSEAUDIO-MODULE-JACK

PAVUCONTROL
so you can select the correct soundcard in pulseaudio for the TWQRQ OUTPUT....the (PULSEAUDIO JACK SINK)

jack audio connection kit
(download qjackctl and it will add the other jack apps)
the settings on jack that i was using are:
48k sample rate, 512 buffer frames, 7 buffer periods,
playback only using the pi's own bcm2835 alsa soundcard
jackd -S ( SERVER SYNCHRONOUS MODE )

JALV.SELECT
makes it very easy to bring up these Lv2 plugins:
- INVADA TEST TONES
- CALF GATE
- SIMPLE DELAY LINE, LINEAR INTERPOLATION

the audio derived cw keying circuits can be investigated here:
http://qrqcwnet.ning.com/forum/topics/what-circuit-for-computer