BH1NYR

XLX074 Reflector Operation Announcement

Sat, 12 Apr 2025 00:00:00 +0000

Notice on Transition to Testing and Research Purposes

Given that personal capabilities cannot meet the relevant compliance requirements for national internet information, effective February 17, 2025, the XLX074 reflector will cease public service and transition to private technical testing and research purposes. We deeply apologize for any inconvenience caused to the HAM community!

Notice on Call Sign Access Restrictions

During operation, it has been observed that some individuals have misused XLX074 by impersonating others’ call signs, causing disruption and impact to the communications of fellow HAMs. Therefore, further restrictions have been placed on call sign access. Starting from 00:00 on April 12, 2025, the reflector will only provide services to amateur radio enthusiasts in Mainland China, Taiwan, Hong Kong, and Macau (call sign prefixes: BA / BD / BG / BH / BI / BR / BY, BM / BU / BX, VR2, XX9). HAMs from other regions wishing to access XLX074 for technical research and testing, please contact via email or WeChat.

Notes and Analysis on ZFS and ECC Memory

Fri, 10 Jan 2025 00:00:00 +0000

1. ECC Memory

The greatest benefit of ECC (Error Correction Code) memory is its ability to detect and correct random bit flips through parity checking, thereby restoring the correct data in memory.

2. ZFS File System

ZFS developers have stated that, theoretically, the ZFS file system itself is no more dependent on ECC functionality than any other file system. Of course, if data in memory is corrupted due to random bit flips (caused by various factors such as cosmic rays), the data recorded from memory to the file system will indeed be incorrect, but other file systems face the exact same risk probabilities. Therefore, under the same conditions without ECC memory, the probability of errors occurring during file read/write operations in ZFS is exactly the same as in other file systems. Furthermore, ZFS retains file checksum information and checksums of that checksum information on the disk, providing superior data security.

Basic Structure and Access Parameters of the XLX074 Reflector

Wed, 01 Jan 2025 00:00:00 +0000

1. Module Configuration of XLX074 Reflector

The XLX074 reflector connects to the Brandmeister network TG46001 (China Nationwide Talkgroup) and TG46010 (Beijing Talkgroup), which are mapped to Module A and Module K respectively, as shown in the figure:

2. Transcoding Settings for XLX074 Modules A and K

Modules A (Nationwide Talkgroup) and K (Beijing Talkgroup) Talkgroup of the XLX074 reflector provide full transcoding capabilities between DMR, D-Star, YSF, NXDN, and P25 digital modes. Radios of different modes can access the corresponding reflector modules through MMDVM clients such as Pi-Star for cross-mode communication. The specific structure is shown in the figure:

iptables' Four Tables and Five Chains and Basic Principles of NAT

Tue, 10 Dec 2024 00:00:00 +0000

This article is translated and reproduced from https://tinychen.com/20200414-iptables-principle-introduction/. It mainly introduces the basic working principles of iptables, the basic concepts of four tables and five chains, and how NAT works. All rights belong to the original author.

1. Introduction to iptables

Let’s first look at the description of iptables from the official netfilter website:

iptables is the userspace command line program used to configure the Linux 2.4.x and later packet filtering ruleset. It is targeted towards system administrators.

Knife Steels Rated by a Metallurgist – Toughness, Edge Retention, and Corrosion Resistance

Sat, 02 Nov 2024 00:00:00 +0000

October 19, 2021 Larrin

Thanks to Bill Smutz, Alex Topfer, Florian Bachler, Brunhard, Art, Rod H, Sach, Jinny Koh, Jon Duda, Cory Henderson, and UPKnife for becoming Knife Steeel Nerds Patreon supporters! And Michael Fitzgerald, Tim Marais, and Head VI for increasing their contributions. All of the experiments shown below are possible thanks to supporters.

Video https://www.youtube.com/watch?v=dg4qcdDba9w&t=109s

I also have a video that summarizes some of the information below while also showing how some of the experiments work. Lots of information is still specific to this article, however. I think they are complementary and you should watch/read both.

Some Written Records of Lu Rong Yu 2682

Thu, 10 Oct 2024 00:00:00 +0000

Incident

The “Lu Rong Yu 2682” case was sentenced in the first instance in Weihai, Shandong on July 19, 2013, with five defendants, including Liu Guiduo, sentenced to death, one defendant sentenced to death with a reprieve, and the remaining defendants sentenced to fixed-term imprisonment ranging from 4 to 15 years. On January 21, 2015, the Shandong Provincial Higher People’s Court rejected the appeals filed by Liu Guiduo, Jiang Xiaolong, Huang Jinqbo, and Li Chengquan, upholding the original verdict. On March 23, 2017, the Supreme People’s Court approved the criminal ruling of the death penalty for the five defendants Liu Guiduo, Jiang Xiaolong, Liu Chengjian, Huang Jinqbo, and Li Chengquan.

The Impact of Wheel Offset on Vehicle Installation

Sat, 08 Jun 2024 00:00:00 +0000

Wheel Offset

Offset is a very important installation parameter for wheels. It determines whether the wheel will rub against components such as the fender, suspension, or brake calipers. For ordinary modification users, wheel offset is relatively difficult to determine among all installation parameters. When upgrading wheel size or increasing width (J value), what offset value is appropriate? Let’s discuss the impact of wheel offset on installation.

I. Understanding Wheel Offset

Offset, also known as offset/ET, is the distance from the wheel’s centerline to its mounting surface. (Unit: mm)

The 36 Dramatic Situations of Carlo Gozzi

Mon, 01 Apr 2024 00:00:00 +0000

In the classic theoretical work The Thirty-Six Dramatic Situations by Carlo Gozzi, he declared that there are only thirty-six dramatic situations.

The thirty-six situations are:

Supplication
Deliverance
Crime Pursued by Vengeance
Vengeance Taken for Kindred upon Kindred
Pursuit
Disaster
Falling Prey to Cruelty or Misfortune
Revolt
Daring Enterprise
Abduction
The Enigma
Obtaining
Enmity of Kinsmen
Rivalry of Kinsmen
Murderous Adultery
Madness
Fatal Imprudence
Involuntary Crimes of Love
Slaying of a Kinsman Unrecognized
Self-Sacrifice for an Ideal
Self-Sacrifice for Kindred
All Sacrificed for a Passion
Necessity of Sacrificing Loved Ones
Rivalry of Superior and Inferior
Adultery
Crimes of Love
Discovery of the Dishonor of a Loved One
Obstacles to Love
An Enemy Loved
Ambition
Conflict with a God
Mistaken Jealousy
Erroneous Judgement
Remorse
Recovery of a Lost One
Loss of Loved Ones

About

Thu, 20 Apr 2023 00:00:00 +0000

This space is updated irregularly and may cover amateur radio, computer networking, and other miscellaneous topics.

If needed, please feel free to reach out via email or WeChat:

Email: op(at)yourcallsign(dot)net (Please manually decode) WeChat: Search and add by my amateur radio callsign

73! Best, bh1nyr