QRQ CW over 100 wpm - tips, techniques and specialized QRQcw GEAR

[Chuck aa0hw]

This video is demo’N a setup to create a custom QRQ CW sine wave, raised cosine edged, ‘keyable’ oscillator

There are already 2 excellent programs for LINUX for a software QRQ CW KEYBOARD… FLdigi and TWQRQ...however, neither one of them are ‘keyable’ - this first video in a new video series on “QRQ CW OVER 100 WPM” uses Fldigi as a tool to build a new software QRQ CW pure sine wave, raised cosine edged, ‘keyable’ oscillator...that you can adjust weight both by TIME and by PERCENTAGE…you can also choose the raised cosine ‘window’, adjust pitch, volume, Q, bandwidth etc… NOTE: at QRQ CW over 100 wpm, many of the cw element parameters become critical for good copy… for example, the edge noise, in spite of the cw element having an 8 ms rise and fall time, increases with cw speed and must be reduced...the edge noise can get so loud as to be 50 percent of what you hear… the VSTs filter it out very well...

NOTE: headphones might be needed in order to hear the subtle cw edge changes
NOTE: only one speaker output is used for the video, to prevent 2 speaker phase issues while listening....you can use a STEREO to MONO adapter if you need to hear this video on both speakers..

first a 1000 hertz tone from Fldigi’s RT QSK CONTROL RT CHANNEL audio output goes to the input of the VST HOST’s first VST PLUGIN, a bandpass filter...which is centered at 1000 hertz...the volume of its output is CRITICAL to get the weight by TIME to work in the following plugins… [ - 1.74 db in this setup ]

the bandpass filter connects to the first REAGATE VST Plugin, where again the threshold volume(-.2 db) is critical to get the weight by TIME to work on the next plugin...another REAGATE…

the 2nd REAGATE PLUGIN is used for adjusting the WEIGHT BY TIME on the CW NOTE...the threshold slider in the middle is set to clone Fldigi’s weight and if you raise the threshold slider higher...you get lighter keying...if you lower the threshold slider you get heavier keying…

the next VST PLUGIN is called “sineCW” and is the heart of the system...where the 1000 hertz tone is used to create a new “cloned” cw element..sineCW lets you adjust the CW PITCH, VOLUME, bandpass filter bandwidth and Q, and rise/fall time

the final vst plugin is called the ENGINEERs FILTER, where we remove any remaining edge noise and select the filter ‘window’ to your preference...each window sounds a bit different...and allows more or less edge noise to get through to the audio output…

a text file from TOM’s, W4BQF, article about copying CW OVER 70 wpm is used...and demoN some of plugins while sending...
https://sites.google.com/site/tomw4bqf/copyingcwover70wpm

http://qrqcwnet.ning.com/forum/topics/home-brewed-software-code-pra...
https://www.image-line.com/support/FLHelp/html/plugins/Minihost%20M...
https://www.meldaproduction.com/MFreeFXBundle
https://www.reaper.fm/reaplugs/
http://www.rs-met.com/freebies.html

[Chuck aa0hw]

QRQ CW over 100 wpm - FLdigi decoding a CW station sending at 170wpm on 30kHZ VLF Band

test to see if FLdigi can decode at 170 wpm...from a CW station transmitting on the VLF BAND, sending a TEXT to CW data stream @30Khz - through a HIGH "Q" FERRiTE ROD TX ANTENNA (& also a high-Q ferrite rod RX antenna)

[Chuck aa0hw]

QRQcw experiment in high "Q" systems to adapt to low power Transmit DiTs due to high Rise/Fall times

The high speed of this extreme QRQqCW test(175 wpm) test to see what can be done to increase the TRANSMIT power of the dits, since the rise / fall time of the dits is too long in a high Q system for the dit to make it to full power/VOLUME for the RF POWER amp to transmit the same power as a DASH etc.. using CW element elongation compensation and DOT/DASH ratio changes to elongate the dits, even though the DASHs/DiTs 'runTOGETHER' , a CW REGEN APP, reagate sidechain gate, can chop off just the peaks of each RX cw element and send that - to the input of FLdigi, to see if FLdigi can decode it