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I am no longer on octodon.social and I will try my best to keep away from some of the people on that server who have taken upon themselves the mantle of upholding the principles of Free Software! I am also observing that mastodon is not so different from twitter when it comes to sane discourse. That is expected - people can't be different when they type on a different browser tab.

I will be mostly tooting my (mis)adventures with amateur radio here and not much about anything else.

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Thank you @M0YNG.

Hello everyone - I am Ramakrishnan. My callsign is VU3RDD and I live in Bangalore, India. I am interested in homebrew electronics and I mostly operate HF/CW at the moment. I have inverted V antenna for 40 and 20m bands.

I do computer programming for a living and work on low level software, cryptography and network protocols..

I have another account octodon.social/@vu3rdd but i thought of separating the radio/electronics toots into a separate account.

Yesterday, I've installed a new homebrew End-Fed Half Wave antenna on the roof, tuned on 18MHz.
This morning, I test it with FT8 (usefull mode for testing).
1st QSO : China
2nd QSO : Japan
and yesterday at night (with very low propagation on 17m), I made a QSO with a Brazilian station !
I think this antenna works 😜

There has been a lot of discussion lately, much of it just plain incorrect, about the relationship between resonance and antenna efficiency. Many incorrectly claim that resonance has nothing to do with antenna efficiency at all, similarly others incorrectly claim that resonance is a direct indication of efficiency. Neither of these statements is true. The reality is that resonance does have a significant impact on how efficient your antenna is, but the relationship is highly non-linear and depends on many characteristics.

Below I have attached a chart hat plots out the total radiation resistance (R_r) vs the measured input resistance (R_in) of a dipole. Efficiency is just R_r/R_in. In other words an efficient antenna will have 100% of its resistance as radiation resistance, and R_in is **always** larger than R_r (since it is essentially ohmic resistance plus radiation resistance). When these two numbers differ significantly an antenna is inefficient. The source for the chart below is here and it gives much of the math if you want a deeper dive:

nptel.ac.in/content/storage2/c

What is important to note here is that at anti-resonance we see a **huge** R_in value and a small R_r value, this means an anti-resonant antenna will have very high losses. Keep in mind the graph is very hard to read for the values <0.5 in length because the resolution isnt high. But there is significant divergence there as well. Notice at ~5/8ths wavelength antenna would exhibit very significant internal ohmic losses due to heat.

#hamradio #rf #radio #ee #electronics #electricalrngineering @Electronics

I really appreciate this distinction:

"It's mainly important to recognize when you are 'flailing' due to lack of understanding versus exploring in order to gain more insight. The goal of flailing is to complete the task, whereas the goal of exploring is to learn new things about the system."

When working on big inherited systems, it's really easy to jump into "fix it" mode prematurely, when really what I need is to give myself permission to spend more time exploring & building understanding.

from macoy.me/blog/programming/Surg

The local newspaper picked up the story of my 13 year old writing the ham radio test. Apparently she was the youngest one who wrote on that day.

And then they left out her name and wrongly spelt my name!

bangaloremirror.indiatimes.com

My 13 year old wrote her ham radio license test today! Hoping to get the exam results in a month or so.

TIL about lichess.org/ , one of the world's most popular chess servers, run entirely on free software by a nonprofit, ad-free, supported by donations with a budget of ~$420K/year according to lichess.org/costs

They've been around since 2010.

As awesome as this is to see, imagine how many free/open nonprofit alternatives to Big Tech platforms would exist if, down to the municipal level, we decided to support them with funding & infrastructure.

I've achieved the Worked All States (WAS) award, making a contact with a station in each of the 50 states in the US. I'd honestly not thought I'd achieve this (or any other) award for #hamradio operations, so this was a real treat. I'm only 3 contacts away from my WAS Digital Modes award and 5 from my WAS FT8 Only award, and maybe 45 from reaching the DX Century Club. Modern digital modes are a total revelation.

Okay there's something really cool I've just learned. If you are continuously recording air pressure e.g. as part of your home automation setup or a weather station then you should really check the data of the last 24h.
You should be able to spot the pressure wave from the volcanic explosion in Tonga earlier today.

It reached my setup in Kaiserslautern at about 20:30.

And the software is getting better and better and good to use as a daily driver now. The couple of days I spent reorganizing the code turned out to be a great decision. Now, adding new features is a lot easier.

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Everything is getting to "too much" for most people these days. The people who tend to be the most resilient have had people leaning on them without a break for a long while, and they're also starting to crack.

If there is someone in your circle you think isn't struggling, reach out to them. There's a significant chance they need a little emotional care right now, because they're probably providing a lot of it to others.

"Jaywalking" as a crime was invented by car companies in the 20s, to shift blame to people on foot for being hit by cars. "Littering" was invented in the 50s by paper cup and tin can manufacturers to shift blame to people who drop trash. The phrase "personal carbon footprint" came from a BP marketing campaign intended to shift blame for climate change away from petrochemical companies to individuals.

When they call themselves "the party of personal responsibility"?

This is what that means.

A lot can be said about moxie's web3 post.

I'd like to consider just one sentence here.

"People don’t want to run their own servers, and never will."

First part is true. But why?

Even my grandma can install android apps. Apps have become so easy because big tech pushed for it to be. Big tech never developed the concept of set-top box-like homeservers, not in their interest. If pushed like apps, homeservers would be easy too!

People don't want to? They never were given a proper chance to!

At the same time I am disappointed that Signal would go down this route and add anonymous crypto/coin payments to its platform. I fear this will bring regulatory attention and potentially be a disservice for privacy in the end-to-end encryption debate…

theverge.com/22872133/signal-c

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Moxie’s analysis of web3 is very interesting and rather revealing. It is puzzling why so many people (want to) believe that it’s “the next big thing” when there are such fundamental and basic issues. Definitely recommended read:

moxie.org/2022/01/07/web3-firs

Got my phone repaired. Rs. 750. Battery replaced, phone is breathing again and healthy. Restored everything from backup. Total cost ~ Rs. 750/- (about 9 Euros).

Stock is now available on the Libre Tech Shop for liberated computers. You can purchase one on the product page below:

libretech.shop/products/lc230

It had been tough to acquire stock for the past few months but I have many units available now.

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