jj1bdx

HamSCI Sunrisefest recording scripts for Airspy HF+ Discovery

• See HamSCI Sunrise Festival Page for the details
• See also wwv-h-wg GitHub repository for the analysis by Jupyter Notebook

Prerequisites

• Linux (tested on Ubuntu 21.10 and 22.04) (May work on macOS but not tested)
• Airspy HF+ Tools
• Advanced Python Scheduler

jj1bdx

ASAHIネットのDS-Liteの終端(AFTR)を取得する

ASAHIネットがDS-Lite対応したので、 自宅の適当なLinuxルーターにて設定しようとして詰まったAFTR取得に関するメモ。

Linuxルーターを使ってる人向けのニッチなものだけど、情報として残しておく。

終端の情報公開について

jj1bdx

# symbolic link to /usr/share/alsa/alsa.conf.d/50-jack.conf
rm /etc/alsa/conf.d/50-jack.conf
# symbolic link to /usr/share/alsa/alsa
mv /usr/share/alsa/alsa.conf.d/50-jack.conf somewhere-else

jj1bdx

#!/bin/sh
# https://sound.stackexchange.com/questions/26633/free-batch-conversion-from-flac-to-apple-lossless-alac
# https://stackoverflow.com/questions/55429909/could-not-find-tag-for-codec-h264-in-stream-0-codec-ffmpeg-flac-to-alac-conver
for name in *.flac; do \
  ffmpeg -nostdin -i "$name" -c:a alac -c:v copy "${name%.*}.m4a" && \
  ffmpeg -nostdin -i "$name" -vf "crop=((in_w/2)*2):((in_h/2)*2)" \
     "${name/%flac/jpg}" && \
  AtomicParsley "${name/%flac/m4a}" --artwork "${name/%flac/jpg}" --overWrite; \
done

jj1bdx

#!/usr/bin/env python3
"""
This program returns number of seconds from now
to the next beginning of day in UTC (0000UTC next day),
truncated into the nearest integer.
"""
import datetime

current = datetime.datetime.utcnow()
nextday = current + datetime.timedelta(days=1)

jj1bdx

Measurement of frequency/timing accuracy for audio interfaces

Kenji Rikitake, JJ1BDX 18-AUG-2021

Objectives

• Finding out long-term/static frequency/timing offset of an audio interface input/output
• To prove timing difference of real-world audio interfaces

jj1bdx

#
# ipsj.cls を upLaTeX 用にしてみる（源ノ明朝・源ノ角ゴシックを使う）
# https://gist.github.com/trueroad/c44312923bf02226c2274388941d0453
#
# ipsj.cls は pLaTeX 専用のようなのですが、
# 試しに upLaTeX で使えるようにした up-ipsj.cls を作ってみました。
# upLaTeX なので pLaTeX では難しかった源ノ明朝・源ノ角ゴシックの利用が
# できるようになります。
#
# 無保証です。これを使った結果何が起きても責任は取りません。

jj1bdx

#!/bin/sh
## remove TeX directories if needed
#sudo /bin/rm -rf /usr/local/texlive
#sudo /bin/rm -rf /Library/TeX
##
umask 022
brew install --cask basictex
#
sudo zsh
umask 022

jj1bdx

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
    <key>Label</key>
    <string>com.wsjtx.sysctl</string>
    <key>Program</key>
    <string>/usr/sbin/sysctl</string>
    <key>ProgramArguments</key>
    <array>

jj1bdx

• Gstreamer Pipeline Samples
  • Video
    • display test video
    • record to file
    • record and display at the same time(queue)
    • record webcam to *.mp4(jetson nano)
    • fps test
  • Audio
  • Mux Video and Audio
• Media File