All Blog Posts (419)

Interrupt Modulated(IM) QRQ CW Mode transmitting and receiving digital information using an analog carrier where the required bandwidth is limited to approximately the frequency of the analog carrier signal. The method is called interrupt modulation and consists of interrupting an un-modulated carrier signal so the…

USING rEvErSe iMaGe CW(riCW) MODE to minimize AUDIO GLITCHEs from poor internet performance with lots of packet dropouts...using an riCW encoder & riCW decoder the riCW encoder injects silence into an audio carrier to represent each CW ELEMENT, the riCW decoder is using CW REGENERATION to convert the silent CW…

ultra-LOW latency REMOTE RIG CW OPERATIONs from a remote laptop on the local area 'wired' network, through router & switches using the NETJACK 2, setup demo from this video:…

using native plugins in REAPER DAW, to create a CW Regeneration "RE-KEYER"...- takes a harsh/raspy square wave input from a 555 keyed CPO output, over to the MIC INPUT(green wave on scope) and converts it into a shaped sinewave CW note output, with raised cosine edges, using 3 reaper plugins: Tone Generator, ReaGate,…

experimental setup to send CW by 'keying' SiLENT GAPS into a narrow band 1600 hertz audio sine wave carrier, for transmit via LINE INPUT of your RIG(LSB/USB)

TRANSMIT ENCODER - by REAGATE's ducking mode output of TX REAGATE goes into a narrow bandpass filter before going to the TRANSMIT line input…

using a 21Khz sine wave oscillator signal source, and 2 individual AUDIO THRESHOLD to CW MIDI output GATEs, and the RECRI KEYER's midi input iambic CW Keyer Module, using just one laptop Stereo sound card to route audio stereo audio outputs and stereo audio inputs a way to use just one stereo audio sound card native to…

uses REAGATE GATE app to trigger a midi note output from the straight key 32Khz signal input to a sound card line input, output of REAGATE app sends a CW MIDI NOTE to key the RECRI KEYER's CW KEYER module https://github.com/recri/keyer

NOTE: this recri…

virtually perfect CW NOTEs in spite of using the lowest possible OPUS AUDIO CODEC bitrate on Mumble "8Khz"

- uses the REVERSE IMAGE CW METHOD for injecting silence into an audio stream, representing each CW ELEMENT; breaking up the 150 hertz stream with silent cw element blocks by using a REAGATE…

using high Q, tuned, resonant VLF ferrite TX & RX VLF antennas(4.078Khz) a QRQ CW square wave into the resonant, tuned, high Q, TX antenna produces minimal harmonics...and even less of those harmonics survive by the time the same type of RX ferrite rod high Q, tuned, resonant, antenna removes even more of the…

working with 4Khz VLF ferrite rod TRANSMIT and RECEIVE antennas that are High Q & tuned to resonance(see previous 2 videos for the more info on the FERRITE ROD HIGH Q antennas being used for TX & RX on 4Khz VLF):…

RECRI KEYER's MIDI INPUT KEYED CW KEYER:

https://github.com/recri/keyer

AUDIO TO Midi CW NOTE OUTPUT converter by REAPER/reagate VST plugin…

https://friture.org/ ;     has versions for WINDOWS, MAC, and Linux

RECRI KEYER's CW KEYBOARD, FILT & MIXER modules used in this video demo:

https://github.com/recri/keyer

CW Keyboard, soundcard SDR MODULEs MIXER & FiLT from RECRI KEYER:

https://github.com/recri/keyer

save 90 percent of your final power amp's battery drain using PDM-CW

instead of sending the full cw element length to the final PA,

PDM-CW sends 1 ms pulses per every 10 ms of cw element instead...

the receiver software patches back in the missing breaks in…

QRQ CW example, by, AUDIO OVER iP via a GSTREAMER raspberry pi TCP AUDIO SERVER and a GSTREAMER laptop TCP AUDIO CLIENT, organized by two PYTHON scripts.

- you can download the TCP SERVER and CLIENT python scripts here:

PYTHON/gstreamer TCP SERVER:…

see this ongoing PLAYLIST with many examples:

http://www.youtube.com/playlist?list=PLfFan4sDonOeK0ipjeVQOkYtV51ogBifV…

using the info at GOOGLE PATENTs, this "TUNED" twin coil ferrite rod loopstick VLF Receive Antenna was put together from some spare parts in the shack, for a test run at 32Khz for receiving a QRQ CW signal at 32Khz…

in AFCW mode, a CW KEYBOARD keys 2 sine wave oscillators at 1500 hertz & 1520 hertz, the beat frequency creates the PULSE DENSITY MODULATED CW beat frequency that will become the PDM-CW TRANSMIT SIGNAL sending to the TRANSMIT INPUT on LSB at 1500 hertz(AFCW MODE)

on RECEIVE, trigger midi mono…

brief demo of using a simple DIODE/TRANSFORMER frequency doubler to get 40Khz CW out of a pi4 headphone jack, by sending to the diode doubler input, 20Khz from the pi's headphone jack

Pi4 HEADPHONE PHONE to diode/transformer/frequency doubler to class D amp input, CLASS D OUTPUT to a series resonant cap to a FERRITE ROD…

full duplex, REMOTE RIG audio over the LAN, via GSTREAMER

https://rumble.com/v2zzcn8-diy-remote-rig-audio-over-lan-low-latency-setup-for-remote-iambic-cw-operat.html?mref=egp3h&mc=atgdc…