HPR

Posted at 2026-10-21 01:33:32 relating to the show hpr4749 which was released on 2026-10-15 by murph entitled murph gives a presentation talk about Hacker Public Radio at the OLF conference

This was very interesting.

I have a comment on microphones though. The host recommended using a "good" microphone when recording an episode for HPR.

While a good microphone would be better than a bad microphone, you don't need a professional grade microphone to record an episode. I have found that an inexpensive gaming headset with microphone works quite well if you are recording a solo episode at a desk.

A headset also has the advantage of keeping the microphone at a consistent distance from your mouth, keeping the audio recording more consistent. It is also much less sensitive to background sounds, making it easier to record reasonably good audio.

So people should not be put off from recording an episode because they think they need high quality equipment. Even relatively inexpensive equipment can be good enough. You can spend $25 or less and have good enough recording equipment. I compare several different recording devices in HPR4658, together with audio samples for those who want to get an idea of what inexpensive kit can do.

On a slightly different topic, the host mentioned my 8 part series on nuclear power technology. I am glad to hear that people found it interesting.

Talking about HPR at conferences is always a good way to promote HPR to both new listeners and to potential contributors. Thanks to murph for the work that he did on this.

Posted at 2026-10-19 22:59:04 relating to the show hpr4766 which was released on 2026-11-09 by Antoine entitled Rant about Audacity 4.0.1

Hi Antoine,

I heard this in the future shows, and was reminded of the controversy surrounding the Muse Group (who own Muse Score) aquiring Audacity in 2021. This prompted installing Tenacity, and therefore recording

hpr3538 :: Installing the Tenacity audio editor

https://hackerpublicradio.org/eps.php?id=3538

Hopefully this is worth a try, and maybe you can report back. :-)

Cheers,
Archer72

Posted at 2026-10-19 21:06:21 relating to the show hpr4747 which was released on 2026-10-13 by Vance entitled UNIX Curio #13 - Replacements for cat

I have never used tsort and I am not sure that I really understand it. I just noticed one day that it was there when looking through a list of commands.

I just ran a quick test to see which distros have it, and found it in Alma, Debian, FreeBSD, OpenBSD, Raspberry Pi, Suse, and Ubuntu. It however is not in Alpine by default.

I didn't try any other distros, but this covers most of the major ones.

The Ubuntu man file states that tsort is useful for scheduling and determining execution order.

If you decide to do an episode on it, then if you can find a few practical examples there is certainly enough to make an episode out of it.

The versions for Linux, OpenBSD, and FreeBSD all have different options. The options for GNU tsort and uutils tsort do the same things as each other, but are not completely compatible in terms of how they are called. This is at least four different versions just among the distros that I tested.

The man pages for OpenBSD and FreeBSD offer much better information about tsort than the Linux man pages that I looked at.

According to OpenBSD, their tsort is compliant with "POSIX.1", but has extensions. They offer volume and page references to Donald Knuth's The Art of Computer Programming for further information.

According to FreeBSD, tsort first appeared in Version 7 AT&T Unix.

Posted at 2026-10-19 07:29:46 relating to the show hpr4318 which was released on 2025-02-19 by dnt entitled What's up with the dates on the HPR future feed in AntennaPod?

This came up on the matrix channel this week.

Thanks dnt.

Should we then set the Future Feed to the date the show was posted ?

Posted at 2026-10-17 06:42:11 relating to the show hpr4747 which was released on 2026-10-13 by Vance entitled UNIX Curio #13 - Replacements for cat

Wow, a lot going on here in the comments. I appreciate it!

Whiskeyjack: Can't believe I didn't think of 'tac' or 'rev' when putting this together. While they are not in POSIX, they are certainly widespread. I honestly have never encountered 'tsort' before - will look into it and see if I can make anything out of it.

candycanearter07: I haven't checked; some implementations of 'head' might support +1, but POSIX does not require it. I always thought of 'tail -f' as being well known, but maybe should revisit that. In practice, I generally use 'less' with the 'F' command instead of 'tail -f' these days, but sometimes it's not available.

Posted at 2026-10-16 12:40:03 relating to the show hpr4717 which was released on 2026-09-01 by Archer72 entitled Visit with a blind Ham operator

Hi Ken and Kevie,

I heard your question about the antenna height in the Community News. The approximate antenna total height is indeed 15 metres, with the whip part of the antenna around 5 to 6 metres.

Cheers,
Archer72

Posted at 2026-10-15 23:51:41 relating to the show hpr4747 which was released on 2026-10-13 by Vance entitled UNIX Curio #13 - Replacements for cat

Hi xmanmonk,

Do you have interests to hackers of your own?

If so, HPR would like an introductory show. :-)

Cheers,
Archer72

Posted at 2026-10-15 21:15:23 relating to the show hpr4747 which was released on 2026-10-13 by Vance entitled UNIX Curio #13 - Replacements for cat

cool ep!
i basically already use head and tail as cat for super long files that have important data at the start/end, also i use an alias to replace cat with batcat

ill also point out the same trick can be used with head since it also supports +1 to print up to the last line in the file

i think a curio on tail would be useful since one of its "hidden" functions (-f, or --follow) is so incredibly useful i wish it was talked about more its amazing for following log files

also also grep is slightly better than cat at catting every file in a directory, since you can use grep -r '' . to print everything recursively, as opposed to cat * which only prints non-hidden files in the current dir

Posted at 2026-10-15 17:00:13 relating to the show hpr4749 which was released on 2026-10-15 by murph entitled murph gives a presentation talk about Hacker Public Radio at the OLF conference

This was an overall fantastic introduction to HPR and the process of recording an episode, but I particularly loved the section about how to start recording - and how much preparation and thinking should go into it.

I think I need the phrase "think, to taste" engraved on a plaque.

Posted at 2026-10-15 10:53:50 relating to the show hpr4726 which was released on 2026-09-14 by Trurl entitled Trurl's intro show

That's an interesting bit at the end: There's more knowledge than humanity can archive (right now).

I've wondered if mankind kinda needs to grow up to be ready for certain ideas which you can not force upon them to accept too early. Like Epicurus' description as everything being made of "atoms" or even Marx' socialist utopia (not the "actually existing socialism" type) becoming reality.

Posted at 2026-10-15 02:04:30 relating to the show hpr4746 which was released on 2026-10-12 by Lee entitled Monotone

To get a good comparison, you would need to compare podcasts that are similar in terms of content. Style and delivery should match the subject, not adhere to some artificial average.

For example, a podcast that mainly consists of two people arguing about something will naturally have greater pitch variation than a podcast that is mainly about someone describing the intricate details of "sed" options.

Having someone speak in excited tones about the "--follow-symlinks" option would not improve the quality of the show from the user perspective.

Given that it is possible to measure pitch variation numerically, it would not surprise me if it were to be possible to process speech to artificially increase the pitch variation in order to normalize that figure, much like is done for audio loudness. That may make for an interesting experiment for someone. That could then be analyzed subjectively to see if the result sound unnatural in the context of the subject being discussed.

Posted at 2026-10-15 01:36:06 relating to the show hpr4747 which was released on 2026-10-13 by Vance entitled UNIX Curio #13 - Replacements for cat

If you use tac twice on a single file, you get the same output as the original file.

So:
tac sample.txt | tac > tactwice.txt

This does not work however if you do this with multiple files as the second operation is on the whole file instead of individual input files.

If you use rev twice on multiple files, then you get the same output as using cat.

rev *.txt | rev > rev.txt

Of course this only works for simple text files.

As a suggestion for a future episode, have you covered tsort yet?

Posted at 2026-10-14 20:04:41 relating to the show hpr4747 which was released on 2026-10-13 by Vance entitled UNIX Curio #13 - Replacements for cat

Another great episode! Certainly keeps the old brain thinking!

Posted at 2026-10-13 19:00:17 relating to the show hpr4746 which was released on 2026-10-12 by Lee entitled Monotone

Hi candycanearter07,

I second the opinion that 'monotone' can be positive, as I conveys the information or story clearly.

Cheers,
Archer72

Posted at 2026-10-13 18:49:00 relating to the show hpr4747 which was released on 2026-10-13 by Vance entitled UNIX Curio #13 - Replacements for cat

Hi Vance,

Thanks for the series and this particular thought experiment. It is one that I will go back to for shownotes reference.

A tip on 'tee' is to use 'tee -a myfile' which append to the stated file.

Cheers,
Archer72

Posted at 2026-10-13 17:53:08 relating to the show hpr4746 which was released on 2026-10-12 by Lee entitled Monotone

i dont understand a lot about audio processing but i think you explained it well! i dont get why HPR being more "monotone" is inherently a bad thing, since its pretty explicitly supposed to be people NOT specializing in entertainment (ie not already trained to speak upbeat) and it doesnt really matter if the actual content is interesting!

Posted at 2026-10-12 22:00:13 relating to the show hpr4738 which was released on 2026-09-30 by Whiskeyjack entitled Programmable Logic Controls - Episode 4

Hi Whiskeyjack,

I'll see what I can pull together, but it may take a while to jog my old memory. Though it has only been 3 years, I find that better notes would have been helpful.

Cheers,
Archer72

Posted at 2026-10-11 20:54:23 relating to the show hpr4745 which was released on 2026-10-09 by Kristoff entitled BruCON interview 1: The BruCON organization

Hi Kristoff,

Thank you sharing your experience at the conference. BTW, the audio in this interview sounded just right.

Cheers,
Archer72

Posted at 2026-10-11 20:44:40 relating to the show hpr4685 which was released on 2026-07-17 by Lennart Benschop entitled Listening to SSB stations in the early 1980s

Hi Lennart and Lucinda,

Ask a Ham radio enthusiast, I have dabbled in shortwave and enjoyed the show. This is one that I will need to hear again. From Kentucky I have received RTÉ National Television and Radio on a single 30 foot wire.

https://www.rte.ie

Lucinda, what does a Field Scientist and Analog builder build and study? This would definitely be of interest to hackers. :-)

Cheers,
Archer72

Posted at 2026-10-11 20:12:15 relating to the show hpr4738 which was released on 2026-09-30 by Whiskeyjack entitled Programmable Logic Controls - Episode 4

Industrial robots have their own controllers which are distinct from PLCs in terms of how they work and are programmed. A very typical configuration for a complex manufacturing cell would be to have a PLC coordinating the overall cell plus controlling various parts of it which are not part of the robot.

The PLC would then tell the robot when to do its job, and the robot would tell the PLC when it was done in a handshake process.

Some robot manufacturers offer robot controllers which have PLC functionality integrated into them. I haven't worked with these, but it is a pretty straightforward feature to have.

In episode 8 in the series I talk about soft logic systems. You will see that running PLC type software on other hardware is in fact quite possible and all the same PLC concepts apply. If you understand PLCs, you will understand logic systems embedded in other controllers as well. You simply need to have an operating system running the different systems which can then communicate with one another and it can be possible to have robot controller software and PLC logic software running on the same embedded computer.

If you have some experience with industrial robots or with their drive systems, perhaps you could do an episode on them for the rest of us?

Posted at 2026-10-11 16:21:22 relating to the show hpr4703 which was released on 2026-08-12 by Ahuka entitled Ebooks and Audiobooks

Your prices on Kobo readers look accurate to me. In fact I paid 169.59 US for the Kobo I ordered, which includes Michigan Sales Tax. Then when it was delivered the Fed Ex delivery guy said I needed to pay over $300.00 US for the tariff. I don't recall the precise amount because I never paid it. I told Fed Ex to take it back and refused delivery. It may have been a mistake by Customs, but that is what happened.

Posted at 2026-10-11 12:54:19 relating to the show hpr4762 which was released on 2026-11-03 by operat0r entitled Surviving the Strike: A Host’s Tale of Lightning

Hi operat0r,

Have you considered using a lightning proximity app? There is one that I have been using (not FOSS), My Lightning Tracker Pro, that I was introduced to by a fellow Ham operator.

https://play.google.com/store/apps/details?id=com.jrustonapps.mylightningtrackerpro

The only purchase in the app is a small donation to remove ads.

The FOSS version that I have yet to try is Blitzortung Lightning Monitor

https://f-droid.org/packages/org.blitzortung.android.app

Cheers,
Archer72

Posted at 2026-10-11 11:30:30 relating to the show hpr4738 which was released on 2026-09-30 by Whiskeyjack entitled Programmable Logic Controls - Episode 4

Hi,

When I started listening to this series, I remembered that in a previous job being told that PLC's were not relevant anymore. And this was at a company that dealt with spindle and servo drives for industrial robots. Little did he know that I was moving to Toyota country (Kentucky), where PLC's were widely used. While I am not in the industry at the moment, this has still been an intriguing and timeless series. I would also think that robotics and PLC's would go hand in hand.

Thanks for all the effort in these episodes.

Cheers,
Archer72

Posted at 2026-10-11 00:50:44 relating to the show hpr4739 which was released on 2026-10-01 by Antoine entitled Happy by shower # 3

Hey, Candycanearter07.
I feel for you. Hope it does good. Yahp.
(I always read your name as candy-cane-eater, like someone who eats something sweet. Only now I paid attention that it's not eater. But I don't know what arter is, and it is not earter, because someone from earth would be earther.) Only thought out loud.

Posted at 2026-10-10 20:37:22 relating to the show hpr4703 which was released on 2026-08-12 by Ahuka entitled Ebooks and Audiobooks

I like being able to point people to resources other than Amazon.

Posted at 2026-10-10 17:35:32 relating to the show hpr4742 which was released on 2026-10-06 by Ken Fallon entitled OLF Call for presentations open

There have been a few comments on background noise in the interview in HPR4742.

Background noise outdoors and in public spaces in general are probably inevitable unless you have a professional grade sound crew and equipment. I did not personally find the background noise in this episode to be a problem in terms of understanding it and I see nothing wrong with it.

If anyone has a similar sort of recording, do not let this sort of noise discourage you from posting it. We will listen to it and enjoy it if the content is good.

I don't know what sort of, if any, filtering was done for this episode. However, too much filtering can be worse than no filtering at all as it can distort the voice signal plus it can actually inject more background noise than it removes. I am not implying this is the case here, I am just pointing out that there are limits to what you can do when recording in a difficult location or in post-processing.

I address filtering in my series on Simple Podcasting, which are HPR4608, 4618, 4638, and 4648.

In HPR4658 - Audio Revisited, I collect and compare a series of sound samples under various conditions with various equipment and then apply various audio filters. This shows that filtering comes down to making a balanced judgment on reducing background noise versus introducing distortion in the voice signal.

However, I am not familiar with auphonic.com. Perhaps Ken Fallon could to an episode on his experience using that method and how well he felt it worked. That would perhaps help other contributors in similar circumstances.

Posted at 2026-10-10 17:12:52 relating to the show hpr4748 which was released on 2026-10-14 by Whiskeyjack entitled Programmable Logic Controls - Episode 5

Thank you for the comment, Archer72. I have added a note to my podcast TODO list to make an episode on Basic Modules and on the 8052AH Basic chip in general.

It should come out after episode 8 in the current series.

If you have any other PLC related topics that you would like me to address, please post a comment below one of the episodes. I have made several episodes on other topics in response to listener questions or comments.

Posted at 2026-10-10 09:59:46 relating to the show hpr4742 which was released on 2026-10-06 by Ken Fallon entitled OLF Call for presentations open

Hi,

I second Ken on the idea of taking the raw audio and processing out the fume extractor noise. This process would make a great episode, or even a few on how to filter out specific noise such as this.

Archer72

Posted at 2026-10-10 09:52:34 relating to the show hpr4748 which was released on 2026-10-14 by Whiskeyjack entitled Programmable Logic Controls - Episode 5

Hi Whiskeyjack,

In the community show comments, you mention knowledge of the 8052AH Basic chip, which would make a great follow-up show.

Archer72

Posted at 2026-10-09 22:41:06 relating to the show hpr4708 which was released on 2026-08-19 by Whiskeyjack entitled Programmable Logic Controls - Episode 1

If you like the series on PLCs, the best thing to do is to comment on each episode as it comes out. This will help to bring it to the attention of more listeners.

If there is something in particular in an episode that you would like to hear more about, then post a comment requesting a follow up on that subject. I will then do a follow up episode dealing with those questions if I am able to answer them.

In one of my previous series, I ended up doing an additional two follow up episodes dealing with listener questions.