Chuck aa0hw's Blog (403)

using different configurations of PVC PIPE(2 INCH Diam) to create a device that will be resonant, increase volume & the sound stage area, and just sit on top of one small speaker, (a radio shack communications speaker)

experimental BiPolar Tesla Coil with a large massive ferrite core, that resonates at 30Khz, to act as a CW transmitter antenna...

CW is sent from a CW KEYBOARD that can send directly at 30Khz, goes out of a sound card that has a sample rate of at least 96Khz...the 30Khz CW output goes to the audio input of a cheap class D…

ZAMGATE PLUGIN INFO HERE:

http://www.zamaudio.com/?p=976

SQUARE WAVE to SINE WAVE by a 3 stage CW AUDIO BANDPASS FILTER setup using 3 sets of tuned ferrite rods,  tuned similar in the way that an antique crystal wireless set would be tuned at the antenna stage, the passive bandpass filter middle stage, and the 3rd filter going to the 1st stage of detection...

GO FROM THIS:…

USES TWO CLi Terminal command line APPs

1. chucK programming language for the CW Keyer, and CW Keyboard

https://chuck.cs.princeton.edu/…

see previous video for this telecoil transmitter for more info in the 1st video description notes https://youtu.be/L1OmVx4mxU8

uses 2 ferrite bobbin core inductor [telecoil transmitter] coils... something like one of these from:…

HAMFEST HELMET PORTABLE VLF RF CW COMMUNICATOR PROTOTYPE - FERRITE ROD LOOPSTick VLF RF 3.8Khz Vertical Transmit Antenna - powered by a portable 12 Volt Class D amp. (ferrite rod = 7 inch long & 1/2 inch diameter TUNED to series resonance at the VLF RF frequency of interest by the appropriate CAPACITOR)

A simple…

resonant cw speaker test by placing a 45 degree, PVC ELBOW over a small speaker

NOTE: the audio you hear on this video is coming straight from the WEBCAM's MICROPHONE

https://github.com/billythehippo/vban-1 (this open source VBAN project has Jack Audio Connection Kit support)

BRIEF demo of someone sending 14.4Khz QRQ CW VLF RF over IP to a Remote RASPBERRY PI 4 and the Pi-4 RE-Transmits the incoming signal over to an indoor VLF Transmit antenna... a local VLF soundcard SDR Receiver Antenna picks up the signal from the PI 4 RE-Transmitter and mixes the 14.4Khz down to 780 hz QRQ CW Morse Code audio tones…

uses a CW REGENERATION method(s)

this example uses the ZamGate 2 channel SIDEchain gate an I/Q sine wave generator is placed on the holding bay ports of ZamGate...

http://www.zamaudio.com/?p=976

the echolink CW AUDIO output from the ARRL…

modified python script for RECEIVING every connecting CW OP

to the FULL MESH, ZEROTIER, PRIVATE IP network is from:

https://brettviren.github.io/pygst-tutorial-org/pygst-tutorial.html

NOTE: other mods…

this video is a followup video from the 1st testing of WebCall for Morse Code Audio QSO here -

https://youtu.be/1h8v865N7IE

2nd test of WebCall to see how well this FREE WebRTC service/APP will handle

QRQ CW MORSE CODE AUDIO…

PulseAudio is not being used, only the DEFAULT ALSA Sound Card...

the default alsa sound card is an ALSA LOOPBACK VIRTUAL SOUND CARD this Zalsa Command brings the YPLog CW AUDIO into the JACK AUDIO CONNECTION BAY for processing through the alsa loopback virtual cable:

jack_load -w -a zalsa_in -i "-d…

VLC has an ios version....

https://www.videolan.org/vlc/download-ios.html

an RTSP SERVER was setup on a PC and a Morse Code CW KEYBOARD was sending CW AUDIO into the input of the RTSP SERVER's audio input ports

BUILT from scratch using INGEN and a bunch of LV2 plugins:

see previous videos about this topic:

https://youtu.be/z6XLEQXCu9E

https://youtu.be/o5TKfq41wnE

also - for even more…

https://keyer.elf.org/

The transmit & receive OPUS AUDIO over IP PYTHON scripts to QSO CW are modified from the original PYTHON SCRIPTS here:…

HARDWARE USED in this example:

***********************************

2 brass spheres

2 bolts/nuts

3 ALLIGATOR CLIP LEADS

2INCH PVC CAP

RUBBER BANDS

small rectangular COPPER PLATE

audio…

GSTREAMER CW SEND, TEXT SEND, SCRIPT used in this example: ********************************************************************

gst-launch-1.0 -v ximagesrc startx=1200 use-damage=0 ! video/x-raw,framerate=30/1 ! queue ! videoconvert ! queue ! vaapih264enc bitrate=1000 ! queue ! h264parse ! mpegtsmux name=mux ! queue !…

brief test to stream a USB WEBCAM along with the laptop's native webcam in the laptop lid at the same time over ip to another location

DEMO one webcam showing the MORSE CODE SENDING GEAR (with audio)

DEMO another webcam(laptop's own webcam) showing the person sending the morse…