Random Wire 137: My duplex AllStar node is also a repeater.
Also: moved a SIP phone to a new network; the GD-88 handheld radio; internet radio for casual listening; coming up, a portable HF rig.
But first, about Random Wire content
Last week, a radio friend mentioned to me that he had found the Random Wire site and tried to read some of my content. “Everything you write is way over my head,” he said. A few mornings ago, a long-time amateur radio operator — an accomplished HF DX operator — said “I don’t understand anything about AllStar.”
As a writer, I find statements like this very concerning.
I’ve had feedback that what I write tends to be “exhausting to read” because there is so much detail, yet I’ve also received requests for more detail. But until last week, nobody had said to me: I don’t understand what you are trying to communicate.
My strategy is simply no strategy. I write about what I’m doing in the world of amateur radio and about things that intersect with our hobby. I write about ideas I’ve encountered or that have occurred to me. Occasionally I will write a guide — a recipe that I call a TechNote — to help others do something that I found challenging to do or easy to forget.
The Random Wire is an exploration of amateur radio as I journey within this incredibly wide “hobby of hobbies.” Much of that journey involves the intersection of computing and radio because those are two of my core interests.
Coming back to the subject of AllStar, perhaps the nature of internet-connected amateur radio is more foreign than I thought. I’ll be thinking about this as I continue publishing the Random Wire newsletter.
If I haven’t said it recently, thank you for joining me on this journey. Please do share your comments and questions so we can all learn.
The ANF101 is also a radio repeater
I’m getting used to the AllScan ANF101 duplex AllStar device, configured as my ASL node 588418. I must say I’m loving this device. The 20-second video capture below (taken with a cell phone, so expect some shaking!) demonstrates great audio quality from a net on the W6EK repeater:
The Retevis RT-85 radio on the left is hidden. That is the radio that receives local RF transmissions on the ANF101. The RT-85 on the right is transmitting, as shown by the red LED on top of the radio. The TD-H8 handheld radio is receiving RF from the RT-85 on the right.
My new, full-duplex AllStar node has two separate radios: one to receive and one to transmit. In my implementation, the receiver is set to 431.180 MHz and the transmitter is set to 147.470 MHz. The receiver takes in audio that arrives over RF, the miniPC processes the audio, and then sends it to the transmitter that sends the audio out over radio.
This is internet-connected amateur radio, but it is more than that. What you are observing in the video is a handheld radio that is used to connect to a local repeater. The ANF101 is a radio repeater. In fact, even if it wasn’t connected to the internet, it would operate just like an RF-based repeater.
CLARIFICATION
My article may not clearly distinguish between the use cases of a personal node and a repeater. I asked David Gleason NR9V (https://allscan.info) for his advice. Below, I’ve paraphrased his educational reply. I appreciate the clarity of his reply and his deep understanding of this topic.
A cross-band full-duplex AllStar node does not repeat received audio to transmitted audio and is therefore by definition not a repeater. It is a personal node, meaning it is used by one person so there is no need to repeat the audio it receives from you back to you. It is simply a link to the AllStar network, forwarding your audio to other AllStar nodes, and transmitting audio from them to you.
A personal full-duplex node could be configured to work as a cross-band repeater, but that is an unusual use case. For example, you may wish to use it as a local repeater at a Field Day site. To do so, you would change the duplex setting from 3 to 2. This would enable RF received by the node to be repeated out over RF.
Most of the time, there would be no reason for a personal full-duplex node to be set up as a repeater. Referring to such a node as a repeater could create confusion in the minds of hams everywhere.
Let that thought sink in for a moment. This is probably obvious to people familiar with AllStar nodes and repeaters, but for the rest of us, it might be a revelation to recognize that a duplex RF-based AllStar node can be configured as a repeater. Once you apply that label to the node, you begin to wonder what other ways the node could be utilized.
In an emergency, or for a localized event, a similar full-duplex node could operate as a temporary, low-power repeater. You could configure the receiver and transmitter to operate like a normal repeater, with an offset and a tone. That would allow people with half-duplex handheld radios to use the node like a “normal” repeater.
As soon as I had this thought, I tried it. I unplugged the node’s Ethernet cable and used two handheld radios for transmit and receive. It worked perfectly.
Yes, the two antennas being close together on the ANF101 might create a desensing issue, but we’re talking very low power levels of 1/2 to 1 watt. I doubt that desensing is going to be a significant issue at such power levels. If it is, you could move the receiving antenna farther away. Says Google:
RF desensitization occurs when a strong interfering radio signal weakens or overloads a receiver, making it less sensitive to the desired signal. Moving the receiving antenna further away from the transmitting antenna is a common and effective method to reduce radio antenna desensing.
To test the range of the ANF101, I connected it to a net and went driving. With the transmitting radio set to low power (1 watt), I picked up readable audio up to 2.5 miles away. Discounting that range a bit still gives about a four-mile circle of coverage in my setting (wooded and gently hilly). (This also means if you don’t need that much range, you should turn down the power or use an attenuator on the transmitting radio to reduce output power.)
Now before you actually do something like this, please be aware there are restrictions on repeaters (auxiliary stations functioning as crossband repeaters) that are not always completely clear. I’m no expert on this. The ARRL introduces this in their FAQ about auxiliary stations at https://www.arrl.org/auxiliary-station-faq.
Despite the restrictions, I think utilizing your full-duplex node as an emergency communications tool might be viable when higher-powered repeaters are not available. Of course, if you built your node around a dual-band mobile radio that can duplex, you could bump up the power a bit for more range, but then you’d also increase the possibility of interfering with other stations. No matter how much power you are using, you’ll want to take a careful look at repeater frequencies in your area to avoid interference.
What are your thoughts? While I don’t recommend doing this, I do like being able to do it in an emergency when no other repeaters are available. Seems like a good tool to have available. I expect I’ll hear some educational thoughts from folks experienced in the world of repeater building and administration — and I hope so!
By the way, must you use a duplex handheld radio to use this duplex AllStar device? No. Here’s an audio capture (with my cell phone) of a test transmission using a TIDRADIO TD-H8 handheld with one VFO set to node 588418’s RX frequency (input) and the other set to the TX frequency (output):
I moved a SIP phone and it still works
Since I’m spending quite a bit of time at my sister’s lake house and not in my Olympia office, I unplugged my SIP phone at the office and plugged it in at the lake house. That phone has my Hamshack Hotline number, a real voice-over-IP phone line, and a connection to an AllStar node.
Did it work? I wasn’t sure if it would, but it did. Hamshack Hotline on the SIP phone works perfectly in the new location and my VOIP.ms personal telephone line also works.
What didn’t work was the connection to AllStar node 588415 in my office. That’s because the SIP phone is configured to connect to an IP address on a private LAN. I’m reading about how to use a Tailscale Funnel to connect the non-Tailscale device (in my case, the SIP phone) to node 588415. The Funnel has not worked yet but I’m still trying. A friend in Italy has this same problem so if I can get a Tailsclae Funnel to work, it might also solve his problem.
Despite no joy (yet) on connecting remotely to my node 588415, my Hamshack Hotline number is configured to connect to my AllStar node 57945. Node 57945 is my “node in the cloud” on a Vultr.com server in Seattle, so even without node 588415, I have AllStar connectivity while at the lake house.
Is the Radioddity GD-88 really a duplex radio?
It’s hard for me to consider the Radioddity GD-88 radio as being a full duplex device.
The two VFOs seem to operate independently. I configured this DMR radio to use the two VFOs in analog FM mode and matched them to the two frequencies of my ANF101 duplex node. Did that work? Kind of.
What is a VFO? VFO stands for Variable Frequency Oscillator. Frequencies for transmitting and receiving are generated and controlled by the VFO.
I can transmit on one VFO and immediately hear my transmission on the other VFO. Unfortunately, I also hear a lot of feedback because the microphone picks up what the other VFO is receiving. I can mitigate this by distancing the speaker from the microphone, but that is a bit awkward.
So yes, the two VFOs can operate as a duplex radio, but this also creates conditions conducive to audio feedback. There are some other configurations I can try and I will. Also, I haven’t tried the radio for DMR yet.
Based on this brief experiment, it’s hard for me to consider the GD-88 as a properly functioning full-duplex radio. Yes, it has two independent VFOs, but it doesn’t function in analog FM quite the way I expected.
I’m still fiddling with the old Icom IC-W32A I bought on eBay. It works but I’m unclear how to configure it to work in duplex with the ANF101 node. Said bluntly, the tech pre-dates my experience in amateur radio. File this under: still working on it.
Internet radio for casual listening
I’ve been curious about the C. Crane WiFi internet radios for a long time but they seemed a bit too expensive for me to take the plunge. I really didn’t understand how they worked, so a few months ago, I bought a used C. Crane device on eBay for not much money, just to try it. I figured that if I liked it, I could buy a better unit sometime down the road.
There was a lot of learning in that purchase.
The Ethernet port on the back had literally been ripped out of the device. That was a surprise, but it still had wifi connectivity, so I could still test the device to see how it performed.
It’s a small device, much smaller than I expected.
The remote was missing so I bought a used one, thinking that would make it easier to use. It didn’t.
Finding stations proved to be more difficult than I expected.
My key takeaway was: this is not the radio for someone who just wants to turn it on and enjoy some listening without any fuss or muss. It was much more hands-on than I had expected.
However, once I finally had it set to a favorite station, I could turn it on and the sound wasn’t bad. I’m in a place where commercial radio signals don’t come in very well, so internet radio with clear audio and no static and no signal fading definitely has some appeal.
I let the idea of internet radio percolate in my mind for a while and continued to read more, now that I was better informed by experience. Did I buy a more modern C. Crane device? No, I ended up purchasing an Ocean Digital Internet Radio model WR-390.
The WR-390 is larger than the C. Crane device. It comes with a USB-C cable but no charger. The WR-390 has a built-in battery. Both devices have bass ports on the back, allowing these small boxes to produce more volume than you might expect.
As a user, though, the big difference for me is Skytune. The Skytune service works very nicely with the WR-390 radio, allowing one to find stations and send them directly to the radio through a web browser. Visiting the Skytune site, you can search by genre, by location, or by a word or part of a word. There are stations available in many languages, covering just about every musical genre.
When you click the red heart for a station, a popup appears. When you enter the IP address of your WR-390 radio, it will send that station to your radio. That’s right, you don’t have to configure everything through the small 2.4” color screen — you can add and manage stations through your web browser.
The popup screen above is where you enter the radio’s IP address. After clicking Send, that station shows up in the display of the radio:
Note that the audio stream is coming through as an Advanced Audio Coding stream, which I find to be a smooth and pleasant audio format to listen to. Here’s a brief video capture that demonstrates how nice the audio sounds:
But there is more. Now that I have some favorite stations stored, I can play them by simply entering the radio’s IP address in my browser (or on my smartphone). This gives me a simple screen of my favorite stations, as shown below. I don’t have to get up, cross the room, and peer down at the small-ish display. I don’t have to find the remote. I can do it from where I’m working on my computer.
The WR-390 is more than an internet radio. You can also connect to it over Bluetooth to stream your audio to the device. And it has an analog FM radio receiver with a telescoping antenna mounted on the back of the unit. Combined with the ability to operate on the internal battery, this makes the device a viable choice for those times when the power goes out and you need to listen to a local radio station for news.
This is more than an appliance. It requires a little more engagement than required to use a transistor radio. But once configured with your favorite stations, it is almost as easy. There are four buttons on the top of the radio for favorites and the IP address interface can hold many more. You don’t have to install software. You don’t have to upgrade firmware. It just works.
For me, the integration between Skytune and the WR-390 radio makes this a very convenient device, compared to the C.Crane WiFi radio. Audio quality is good, the radio isn’t too large, and the internal battery is a useful feature. If you’ve been toying with the idea of an internet radio for casual listening, I encourage you to check out Digital Ocean radios.
Coming up!
zBitx HF portable radio
A zBitx radio by HFSignals is ordered and will be on the way soon. (See the zBitx product page and the user manual for more information.) While this is not the most power efficient QRP high frequency radio (see Vince VE6LK’s review, under the “Here are the Cons” heading), I’m attracted to this device because it is portable and has some digital modes built in. I like the idea of putting together a small, portable kit to carry in the pickup. That would allow me to set up and do some Parks on the Air (POTA) operating from time to time.
I’m not a CW operator (yet) so the weak points of the radio involving CW don’t really concern me. Perhaps (hoping!) the CW-related issues will get addressed in firmware updates.
I’ve also ordered a G7UFO Turret Mini Microphone for it. I requested the mic with a gray body and a red (for transmit) button. With international shipping, the cost was $55.00. My fingers are crossed that this will provide better audio during voice transmissions with the zBitx.
I’ve also picked up a few more items, including a power delivery-compatible USB power bank, a 5-amp USB cable to connect the power bank to the zBitx, and a few more adapters. File this under: more to come.
Batteries and more for Yaesu FT-5DR and Kenwood TH-D74
A while back, I ordered an extended battery from W0AEZ Radio Gear for my Yaesu FT-5DR handheld. (This is also available in kit form if you want to save $20.) The FT-5DR is the radio I usually use with my hotspot for YSF connections, so a longer operating time is desirable. Along with that, I also ordered a desk charging cradle and a battery for my older Kenwood TH-D74 handheld.
These items just shipped:
1x Desk Cradle for BP-Y14L
1x BP-Y14L v6 Ham Radio 2.0 | Complete | Yaesu FT1 FT2 FT3 FT5 VX8 | 5Ah Capacity | USB-C Charging
1x BP-K75L v1 | Complete | TH-D7X | 5Ah | USB-C Charging
(I do like patronizing small businesses, even though sometimes this increases my risk.)
Once these items arrive, I’ll report on how well they fit and work. Find all of W0AEZ’s amateur radio gear at https://w0aez.com/collections/ham-gear. You’ll find more than batteries.
Closing
I’m still helping with my wife’s recovery for several hours a day. It certainly takes a toll but amateur radio is a welcome diversion. I enjoy fiddling with technology — trying new things and fixing old things. And I enjoy the amateur radio operators who represent some of the smartest people I know. It is an amazing hobby.
If you know people who enjoy technology and solving problems, this could be a great hobby for them. If you know folks who like to socialize with people from all over the world, this could also be a great hobby.
Sometimes, we may put people off when we talk about what we do instead of why we do it and what we get from amateur radio. I like to solve problems, and amateur radio gives me that. I like to learn from other people, and I do that by listening to many people. Becoming a radio amateur and growing in the hobby presents continual opportunities for lifelong learning. I’m glad to be here and to know so many great amateurs.
73 to all. Remember to touch a radio every day!