Random Wire Review: Issue 118
January 17, 2025: Debian upgrade available (but wait). TechNote on DVSwitch Mobile for AllStarLink. Icom SP-35 speaker. PoE switch (don't buy). USB radio charger, Linux, and an active antenna.
Contents
0. Note for Debian 12 users
0.1 Debian upgrade from 12.8. to 12.9 available
0.2 AllStarLink users: don’t do it yet
1. TECHNOTE: DVSwitch Mobile for AllStarLink
2. ALLSTARLINK
2.1 Supermon 7.4+ on AllStarLink ver 3
2.2 How to find active AllStarLink nodes
3. RF RADIO
3.1 Inexpensive shortwave active antenna
3.2 USB charger for Yaesu VX-6R
3.3 Small speaker for FTM-300DR mobile and WIRES-X
3.4 Lowering your noise floor the easy way
4. NEWS
4.1 Always good sources
4.2 Interesting finds
4.3 Technology
5. LINUX
5.1 There’s a new Debian in town…almost
5.2 Experimenting with Arch Linux
5.3 Reduce RAM in my Linux test machine?
6. TECHNOLOGY
6.1 AA Li-ion cell with USB recharging
6.2 Nitecore ultra-slim power bank
6.3 New PoE switch with SFP (do not buy)
7. CLOSING
7.1 Do you do APRS?
7.2 My FCC license expired?
Welcome to the 118th issue of the Random Wire newsletter. This one seems particularly heavy on computer-y topics, probably because I’ve been battling with computer things for the past month. I have enjoyed some amateur radio time, including checking in on some AllStarLink and YSF/WIRES-X nets, but most of my radio time has been spent listening while I monkey with hard drives, switches, firmware updates, faulty Ethernet cables, and more.
For radio folks, I recommend slowing down at item 3.3, the Icom SP-35 speaker. It’s a great performer and at $35, it’s also a great value.
AllStarLink users will find the Debian upgrade section (section 0) interesting. The takeaway is don’t upgrade your Debian-driven AllStarLink node quite yet. Also, learning that DVSwitch Mobile (free) and an AllStarLink node number (free) means you can be on AllStarLink worldwide at no cost is astounding. See the TechNote reference below in section 1.
IT folks may find my long piece in item 6.3 about the STEAMEMO Power-over-Ethernet switch of interest. Bottom line: don’t buy it. I learned a lot with this particular switch. More on that in issue 119!
With that, I’ll leave you to wade through a pretty hefty Random Wire newsletter. I know this isn’t everyone’s cup of tea, but I also know there is a little something for most everyone in issue 118.
Please do share your questions and comments so we can all learn.
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0. Note for Debian 12 users
TL;DR: An upgrade from Debian 12.8 to Debian 12.9 was just released. Use the “sudo apt update && sudo apt full-upgrade -y” command string to install it. But if you are using Debian 12 for an AllStarLink 3 node, don’t upgrade yet as 12.9 introduces distorted USB transmit audio.
0.1 Debian upgrade from 12.8 to 12.9 available
If you haven’t updated your Debian 12 Linux computer in the past few weeks, there are new packages due to a newly released upgrade to Debian, taking Debian 12 machines to Debian 12.9.
Install with the usual update and upgrade dance:
sudo apt update && sudo apt upgrade -y
Note that the recommended procedure is to run apt update and apt full-upgrade. I did that on one machine and it sent messages about removing DAHDI. It apparently didn’t really upset Asterisk (verified after rebooting) but it was a bit unnerving. I used apt upgrade on the other machines.
(What’s the difference, you might wonder? Well, apt upgrade only upgrades currently installed packages, while apt full-upgrade “will upgrade currently-installed packages, install new packages introduced as dependencies, and remove packages which are broken by upgraded packages.”)
The upgrade takes a while, longer than you may be used to when upgrading. I don’t recommend the -y flag when upgrading, but in this case, I had already run most of the packages the day before so the final upgrade to Deb 12.9 was simpler.
On my machine, running uname -r after upgrading revealed version 6.1.0-28-amd64. Hmmm. That’s odd, because the upgrade files were supposed to bump it to 6.1.0-29-amd64. A reboot resolved this minor issue.
I had to reboot my other nodes after upgrading them, including my node-in-the-cloud on Vultr.com.
Bottom line: use apt full-upgrade and reboot your machine when the upgrade process has completed.
0.2 AllStarLink users: don’t do it yet
The day after I pushed upgrades to my Debian 12 AllStarLink nodes, David Gleason NR9V noted poor audio for upgraded nodes:
There is also active discussion of this issue on the AllStarLink community forum.
The takeaway here is if you use your Debian machine to run AllStarLink 3, don’t upgrade your Debian 12 nodes quite yet! There is an unresolved issue that may affect your transmit audio quality.
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1. TECHNOTE: DVSwitch Mobile for AllStarLink
TechNote 4 (Configuring DVSwitch Mobile for your AllStar node) describes and illustrates how to configure the DVSwitch Mobile app (Android only) to connect to your AllStarLink node, and with DTMF commands, connect to other nodes.
A free app and a free node number makes this the least costly way to get on the AllStarLink network!
But hold the phone — did you know you don’t need a physical node to use DVSwitch to connect to ASL nodes? You need a node number to use “WT Mode” (WT for Web Transceiver) but you don’t need an actual node.
Learn more at https://www.randomwire.us/t/technote.
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2. ALLSTARLINK
2.1 Supermon 7.4+ on AllStarLink ver 3
Six months ago, the Ham Radio Crusader (aka “Freddie Mac” KD5FMU) published a guide to installing and configuring Supermon 7.4 on AllStarLink 3. While I prefer to use AllScan to control my ASL 3 nodes, I recognize that some may prefer Supermon. If Supermon is what you like, here you go!
Freddie Mac has a treasure trove of content for AllStarLink users, including:
AllStarLink 3 Time & Weather Announcement Script File Install
Automation for ASL 3 AllStar - Connect & Disconnect on a Schedule
If you use AllStarLink, binging on the Ham Radio Crusader’s content is well worth your time.
2.2 How to find active AllStarLink nodes
So you’re on AllStarLink but wondering where all the other people are? Go to https://stats.allstarlink.org/stats/keyed and select active nodes from that list.
To see what may be near you (or in a location you are interested in), visit https://stats.allstarlink.org/maps/allstarUSAMap.html
I made a favorites list for the Portland-Vancouver region with 45 entries. I’m thinking it might be enjoyable to have a geographically-focused net from time to time, or at least a list of hams in the area to contact.
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3. RF RADIO
3.1 Inexpensive shortwave active antenna
I’m pleasantly surprised that a $40 active receive-only antenna works as well as it does for shortwave listening.
MLA-30 Loop Antenna Active Receiving Antenna 100kHz - 30MHz for Short Wave Radio
I tested the MLA-30 with my VX-6R, with a simple AM/FM radio, and (using a BNC-to-SMA adapter) with an ATS25max receiver. I found that I could pull in stations that the stock antenna didn’t hear. If you’re into listening and perhaps in an area where reception of your favorite station is marginal, you might consider this inexpensive active receive-only antenna.
3.2 USB charger for Yaesu VX-6R
I love a small gadget, especially if it makes my life easier. This is one of those things:
For $12, this USB cable charges my Yaesu VX-6R handheld in the car and at my desk. It’s small enough to fit into any of my computer bags without the awkwardness of the Yaesu charger. No wall wart taking up space in my back or in the center console of my pickup truck. Since I also have the VX-7R, VX-8R, and FT-70DR, this one little thing does quadruple duty for me.
3.3 Small speaker for FTM-300DR mobile and WIRES-X
For my ham radio station, I’ve been liking vintage Heathkit HS-1661 speakers. To my ears, the audio through the the HS-1661 is quite pleasant. However, the speaker enclosure is not small and space is at a premium in my location.
I picked up a small Icom SP-35 speaker for the affordable price of $35 to see how it sounds. I expected it to be tinny and weak but was pleasantly surprised by the richness and clarity of voices through the Icom speaker. It’s a little bit brighter than the HS-1661 and to my ears, that’s an advantage when listening to human voices over the air.
Here is the top of the Icom box with a U.S. quarter for scale:
When you open the box, all you see is the speaker with the attached extension wire and mono plug:
The Icom SP-35 speaker is small enough to fit into most mobile radio installations. The adjustable mounting bracket also serves as a brace (desk stand).
The Icom SP-35 speaker is dwarfed by the vintage Heathkit HS-1661 enclosure.
I liked the Icom SP-35 speaker enough that I bought a second one. One unit is strapped behind the headrest in my Honda Ridgeline truck and plugged into my Yaesu FTM-300DR mobile radio. It makes a great difference to have audio near my ears instead of muffled under the seat.
The other SP-35 speaker is in my shack. I keep going back-and-forth between the Icom speaker and the Heathkit speaker. I like them both. Here’s a comparison of audio samples through the HS-1661 speaker, then through the Icom speaker, and then through the on-board speaker in the FTM-300DR. These clips were collected from a net heard on my WIRES-X Portable Digital Node on January 7, 2025. I added some opening and closing music, and recorded my voice, using Audacity.
(Intro and outro music credit: “Short Upbeat Jingle” by alanajordan from Pixabay.)
An interesting observation is that after the first clip, I had to turn the volume up slightly for the Icom speaker to produce the same volume as the Heathkit speaker. And then I had to turn up the volume again for the built-in speaker output to match the Heathkit speaker volume. (Most likely, the Heathkit speaker has lower impedance [ohms] than the other speakers.) To my ears, the Icom external speaker presents the easiest-to-understand audio, followed by the Heathkit speaker. The built-in speaker is muddier sounding, making it harder for me to understand what is being said.
For less (probably) than what you’ll pay on eBay for a Heathkit HS-1661 speaker in good condition, you can get a modern, very small, and good sounding Icom SP-35 speaker. If space is at a premium for you, or if you need a speaker extension for your mobile rig, I don’t think you’ll go wrong with the Icom SP-35 speaker.
3.4 Lowering your noise floor the easy way
When I ran across this article, I immediately thought of a few of my ham radio friends who were recently talking about RF interference.
The author describes the process of flipping circuit breakers to isolate the room where the RF interference is coming from, and then:
His noise problem went away with the living room breaker, which led to pulling plugs one by one until he located the culprit: a Roomba vacuum’s charging station.
By the way, if you’ve not perused Hackaday’s collection of numerous articles tagged as “amateur radio,” it’s easy and interesting: https://hackaday.com/tag/amateur-radio/
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4. NEWS
4.1 Always good sources
4.2 Interesting finds
Ham radio operators, new and old, assemble at conference in Brookville
Ham radio is still a disaster lifeline, even in the iPhone era - here's why
Amateur radio volunteers provide and maintain crucial communication links when hurricanes strike
Call for Nominations: ARRL Awards Recognize Excellence in Ham Radio
As Cord Cutting Grows More Americans Will Listen to The Radio Than Watch Traditional TV in 2025
4.3 Technology
What are your favorite news sources? Have you run across a particularly interesting article to share?
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5. LINUX
5.1 There’s a new Debian in town…almost
Debian 13 “Trixie” was released on December 31, 2024. Sounds exciting, doesn’t it? Something new! However, it is just the installer, not the final product.
I caution fellow explorers that this is the alpha release of the installer. So not only is this not a full Debian 13 release, it’s just a test of the installer. I did try the Trixie installer on an old Lenovo ThinkCentre M700 and it went fine. The netinst ISO from Debian installed Debian 12.8.
5.2 Experimenting with Arch Linux
I’ve been in the Ubuntu/Debian world for several years and have largely ignored the other flavors of Linux. Arch is interesting, both because it is what HamVoIP runs on and because it seems stable, like Debian is stable. However, the couple of times I poked my nose into the Arch world, I felt rather confused.
Fast forward and I just installed EndeavourOS, a flavor of Arch. I selected the KDE Plasma display environment. It looks nice and it’s fast.
The KDE Plasma desktop is a familiar environment and the helper included with EndeavourOS is a nice touch. I do want to like this version of Linux. I suppose I can adjust my thinking to adapt to pacman and yay as package installers instead of what I’m used to.
However, the kiss of death for me is that I can’t get the system to show me a desktop environment when I remote into the machine. I have a lot of computers but only a couple of computer monitors, so on Linux builds, I use remote desktop protocol (RDP) to connect to the Linux machines. The problem with EndeavourOS is when I remote into the machine, I get no desktop: just a black screen, and after monkeying with this for four hours, a green screen.
I’ve reinstalled the operating system four times (and I have to say it’s a very nice installer). I can get the system working as a desktop computer very easily. But configuring it to run without an attached monitor, keyboard, and mouse? That has been my brick wall.
The Arch Linux community is not small, but it doesn’t seem to have the depth of knowledge online that the Ubuntu and Debian communities enjoy. I’m still looking for a solution. I suspect there are some Arch-focused packages that will smooth the way for me. My experiments with Arch Linux are not over yet.
5.3 Reduce RAM in my Linux test machine?
I don’t think I need 32 Gb of RAM in my Debian 12 Linux test machine with the KDE Plasma desktop. I pumped up the amount of RAM because I had heard that Plasma really needed a lot of RAM. However, monitoring shows low CPU and RAM utilization at idle. It looks to me like I could pull back to 16 Gb of RAM and not notice the difference.
This machine is running on a Dell OptiPlex 7050 Micro Mini PC with an Intel i7-7700T CPU that has 8 cores.
The two screenshots above were taken with the machine running headless, meaning I used a remote desktop program to access the machine.
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6. TECHNOLOGY
6.1 AA Li-ion cell with USB recharging
“Charge smarter, last longer,” says the Nitecore website.
Nitecore’s NH2400 battery pack includes four 2400mAh USB-C rechargeable batteries, a 4-split charging cable, and a convenient storage case. Fully compatible with devices that use standard AA batteries…These batteries offer stable, consistent output and a longer runtime per charge compared to traditional rechargeable NiMH AA batteries…With a higher capacity than typical NiMH or alkaline AA batteries, the NH2400 minimizes the need for frequent recharging or battery swaps. The NH2400 also features a USB-C charging port with built-in indicators for charging status. The included 4-split charging cable is compatible with USB-C and USB-A power outlets and allows you to recharge all four batteries simultaneously in just three hours.
Seems like a dream come true. The Nitecore Store is currently backordered on these but more are expected around the end of January. I’ll be ordering some of the AA batteries when they become available. Even though most of my flashlights now use 18650 batteries, I still have several that eat AA batteries.
6.2 Nitecore ultra-slim power bank
While you’re thinking of Nitecore as a brand, consider this pass-through battery pack. “Pass through” means you can recharge the battery even as it is powering your USB-C device. Being able to charge the battery while using it to power another device is a great convenience.
This little brick is actually pretty slim! It only has two USB ports, but most of the time, that’s all I really need.
The two large flat surfaces of the power bank have a carbon-fiber print on them. The plastic looks a bit like what we see on new radios — you know, that transparent or semi-transparent film you’re supposed to remove. That is not what is on this brick. The surfaces on this power brick look a bit like that but they are actually part of the build. Don’t remove them.
6.3 New PoE switch with SFP (do not buy)
TL;DR: This affordable 11-port Power-over-Ethernet switch actually has 8 PoE ports, two LAN ports, and one port with gigabit speed if you also buy the correct SFP module. The switch gets warm if the top cover has something placed on it, so leave it clear. The switch seems just as zippy as the small TP-Link PoE it replaces. However, the Ethernet port in my desktop computer died after I started using this switch, and on that basis, I can’t recommend the switch.
6.3.1 New switch
The occasional failure of my Power-over-Ethernet switches caused me to purchase a replacement. I picked up a smaller PoE switch to test as a temporary backup if needed:
By the way, why would you want a PoE switch? Once you get a couple of devices that can be powered over an Ethernet cable instead of finding another place to plug in a power adapter, you’ll be hooked. My SIP phones are PoE devices. Some of my small computers are PoE. You can use a PoE switch with devices that don’t use power over your network cable, but having such a switch gives you quite a bit of flexibility as you build out your technology stack. The best part is needing to only run Ethernet to the device to supply both power and data.
OK, back to this surprisingly inexpensive $36 switch. It feels reassuringly hefty. I did a bit of a double take when I retrieved the Amazon package as it felt a bit heaver than I expected.
6.3.2 Unboxing
Here’s the bottom of the box:
Here’s what you see when you open the box:
Here is the bottom of the switch:
And here is the front panel of the switch:
6.3.3 Instructions
The user manual is very short:
6.3.4 FDDI port and SFP adapter
Note that the second page mentions FDDI (Fiber Distributed Data Interface). You wouldn’t think an inexpensive switch would support an SFP (Small Form-factor Pluggable) adapter, but this one does.
That looked so interesting that I ordered a $33 module that converts the fiber channel to Ethernet, thinking I can use this port for the main connection to my router.
Using an SFP module would give me that eleventh switch port. To be clear: this is really a 10-port switch (eight PoE ports and two LAN ports) if you are not going to use the FDDI.
(Here’s an interesting intersection of terms: the SFP module is a transceiver. “Ethernet SFP module, known for its compact, small form-factor pluggable design, also referred to as a mini-GBIC (gigabit interface converter), is a compact modular transceiver employed across network switches and servers.” That caught my eye as I hadn’t really thought of Ethernet as part of a transceiver system…but clearly, it is.)
Note that SFP does not support Power-over-Ethernet. I should be able to use the FDDI port to connect to my router, and with the switch plugged into the mains, I would have PoE through the eight PoE ports. My test with the SFP module is more of a proof-of-concept thing, just to make sure it actually works.
The SFP module is quite small:
When placed in the switch (and it only goes in one way so you can’t make a mistake) it sticks out a bit:
If you do this, you’ll need to know how to remove the SFP module from the switch. There’s a trick to it: the gold frame at the opening of the module is really a hinged latch. Lifting the latch releases the SFP from the port. It’s obvious once you know this but it can be confounding if you don’t.
6.3.5 Artificial intelligence
I’m not sure what AI means on the front panel (and in the user manual) for this switch. From the user manual:
This model supports AI intelligent detection. When the monitoring equipment crashes or other network abnormal interruption occurs, it can judge the intelligent restart of Poe port equipment through AI algorithm. Automatic network optimization: automatically judge the network signal transmission status, intelligent switching of ultra long distance mode, long-distance transmission is stable and does not drop the line.
That doesn’t sound like an AI engine to me. However, this feature is switchable on the front panel. In the photo below, I’ve powered on the AI engine, as indicated by the green LED. Note that the front panel AI switch says “ON: AI & Extend“ so this switch also allows the switch to be used for longer runs of Ethernet cable. (My runs are very short so the AI switch will be turned OFF in my use of the device.)
6.3.6 How I’ll test it
I’m hoping this proves to be a stable switch. To test it, I’ll swap it into my work office network and set aside the smaller PoE switch that is currently in place. But hey: $36? At that price point, it sure seems like it’s worth a roll of the dice. (UPDATE: The switch is fast. It feels a little faster than the TP-Link PoE switch I had been using. Notably, though, I’ve had zero issues with the TP-Link switch!)
By the way, there are no feet on the bottom of this thing. I prefer to have some airflow around the device so I bought an assortment of rubber feet. I’ll also use them as rubber bumpers to quiet doors and cabinets around the house.
So did the SFP module work? No, I chose the wrong adapter. I did some searching online and concluded it was worth trying a different brand adapter and a CAT 7 Ethernet cable. Did the other adapter work? No. Still wrong. By now I was committed to solving this, so I bought a third SFP module. Wrong again.
(This was a teachable moment for me. I had not been exposed to SFP modules in my previous IT work because we used very inexpensive hardware that did not use this hardware. So while it cost me some money, I am happy to learn something new, and to save you from making the same mistakes.)
After thinking about this for a bit, I purchased a fourth SFP module. The FDDI port on the switch is marked for 1 Gb so I looked for two things: an SFP module (not an SFP+ module), and a speed of 1 to 1.25 Gb. I’m pleased to report the Cable Matters module does work! If you buy this switch and want to add an SFP module, pay careful attention to the speed rating of the module.
The box for this device describes it as: “1.25Gbps SFP to RJ45 Transceiver Module.”
The good news is that this basic SFP module is cheaper than most others. The SFP+ modules seem to be more easily found as they support small business and enterprise switches. My new switch, though, is more basic than that. The other positive thing to report is that with the module in the FDDI port, connected to my router, I have eight PoE ports available and two LAN ports. The switch is working well.
I also note that the switch gets warm if you put something on the metal case. While no ventilation holes were blocked, it appears that the top of the case also helps to get rid of excess heat. Once I removed the item I had on top, the case stays cool.
6.3.7 Spare switch
Considering my luck with PoE switches, I decided to buy a spare switch for my home network. In the image below, you can see the new, cold spare sitting on top of the working switch:
That dusty router on top of the switches? That’s a GL.iNet Flint 2:
Redundancy can be a reasonable way to help ensure uptime. I depend on my home network for work, so having some spare equipment (router, switch, cables) provides some peace of mind.
6.3.8 Final words
After testing the new STEAMEMO PoE switch for a few hours, the Ethernet port in my desktop computer died. I’ll report more on this in issue 119.
As a scientist, I know that correlation does not equal causation. But it’s hard not to link the two things together in this case. What I think happened is the Ethernet on my older desktop motherboard is not 802.3af/at compliant, and if so, then the PoE switch may have killed it. My temporary workaround is to use a USB-to-Ethernet adapter. That solution seems to be working well with the PoE switch. I also have a new PCIe Ethernet card arriving soon so we’ll see if it survives.
Based on this experience, I can’t recommend the STEAMEMO switch at this time.
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7. CLOSING
7.1 Do you do APRS?
Michael NA7Q has been doing some wondrous things to the APRSDroid app. Check out his latest announcement at https://na7q.com/aprsdroid-release/.
I do wish I could get the APRSDroid screen displayed on my infotainment center screen in the Honda Ridgeline, but that is highly unlikely to ever happen.
A few days after I wrote this, I saw an announcement about APRSDroid in the always great Zero Retries newsletter. It’s great to have multiple people covering APRS topics!
7.2 My FCC license expired?
I was registering for a help desk that requires a copy of my FCC-issued amateur radio license, so I logged into the FCC License Manager and downloaded my license…and it said it expired in July 2023!
What? Oh no. My heart started pounding as I stared at my computer screen in disbelief. No, no, no, no, no!
I remembered paying to renew my license at the end of May 2023. I dug through my old emails to find the communication from the FCC, dated May 31, 2023, that said: “This email is to notify you of the recent grant of your application(s).”
By this time, I had been stressing over this for about 30 minutes, feeling my blood pressure rising and getting more worried than I care to admit.
Finally, I went back and carefully examined the license. It was the end of a very long day and my eyes (and brain) were tired. What I read on the downloaded license as 2023 was actually 2033.
Oh blessed relief. And time to take a break!
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And that’s a wrap to a rather rambling issue 118. My mind has been busy even if I’ve had little time for radio play. I hope you found something interesting in this edition of the Random Wire newsletter. Please do forward it to friends who might find it interesting!
A very big thank you to those who have chosen to contribute toward the Random Wire by buying me a coffee or purchasing Amazon products linked in these newsletters. Every little bit helps and I appreciate the support.